index ( testing procedures ) - · pdf file36 elcb+mcb ( refer testing of elcb and mcb)--- 18...

1

INDEX ( Testing Procedures )

SR. NO. MATERIAL DESCRIPTION PAGE NO. FILE NO.MTS/FL/MTL

--- PREFACE 5

1 Black adhesive tape 6 2

2 Cotton Tape 10 2

3 HT Bitumen tape 12 2

4 Impregnated paper separator 14 2

5 LT Bitumen tape 16 2

6 PVC tape 19 2

7 HRC FUSES 21 3

8 Cutouts 25 3

9 Fuse Base 27 3

10 Non fusible transformer link 630 amp 30 3

11 Neutral links 33 3

12 T.L. Fuses 35 3

13 HPSV Lamp 37 5

14 Lanterns 39 6

15 Ballasts-HPSV 41 7

16 11KV/110V PT and 33000/110V PT 44 8

17 Metering / Protection CTs 51 9

18 Adapter for Bank Type Metering CT 57 9

19 Ring CTs ( LV metering) 59 9

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INDEX( Testing Procedures )

SR.NO.

MATERIAL DESCRIPTION PAGENO.

FILE NO.MTS/FL/MTL

20 Summation CTs 61 9

21 RCC Trough/Tiles 62 10

22 Power Capacitor (28KVAr, 56KVAr) 64 11

23 Capacitor for Lantern 10µF, 33 µF,40 µF 67 11

24 Cable in Coil form (unarmoured) 69 13

25 L.V. Armoured Cables 71 14

26 H.V. Cables 73 15

27 400 mm2/1C copper XLPE Cables 75 15

28 Lead Pipe 77 16

29 Pluming Metal, AL & CU Solders 79 16

30 Compounds Inner Sleeve 80 17

31 Compounds Outer Sleeve 84 17

32 Epoxy Jointing/Termination Kits 87 17

33 Air Break Contractors 89 18

34 MCB 92 18

35 MCCB 94 18

36 ELCB+MCB ( Refer testing of ELCBand MCB)

--- 18

37 ELCB 96 18

38 Paints 99 19

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INDEX (Testing Procedures )

SR.NO.


FILE NO.MTS/FL/MTL

39 Tarpaulin General/ Grey/ Fabric 104 20

40 Lugs/AL. Ferrules ( AL, Copper ) 106 22

41 Brass Glands 107 22

42 Bakelite Sheet 108 23

43 Synthetic Mat 113 23

44 Hand Gloves 116 23

45 Gum Boot 118 23

46 Safety Shoes 120 23

47 Cork Sheet 122 23

48 Transformer Oil

B.D. Value

Tan Delta

Acidity

PPM

Flash Point

Viscosity

123

125

129

132

136

138

24

49 Copper Winding Wires 140 25

50 G.I. Earthing Wires 142 25

51 Fuse Wires 145 25

52 Plastic Putty 147 30

4

SR.NO.


FILE NO.MTS/FL/MTL

53 Fuse Switch Unit/Switch FuseUnit/ICTPN/ICDP

150 36

54 Distribution Transformer (LossMeasurement)

153 45

55 AL/CU Busbars/CU Earthing Plate, CuStrips.

161 54

56 Ignitors 163 56

57 L.V. Distribution Pillars, L VBoards/Mini Pillars

166 57

58 Energy Meters ( static ) 167 61

59 Compact Fluorescent Lamp & Adapter 174 62

60 Ceiling Fan/Table Fan 175 63

61 GSM of paper 177 64

62 Choke/20/40 watts 178 65

63 Electronics Chokes/Tube lights 180 67

5

MATERIAL TESTING AND STANDARDS DEPARTMENT

General procedure followed in MTS department:

1. Materials are received against following references:a ) Tender: ( Samples are supplied along with tender)b) Inspection Memo: (Samples are to be selected as prescribed in

testing procedures ).c) Departmental Letters of Various dept. of Supply branch: ( Materials

are brought /taken back by concerned departments )d) Departmental Letters of Bldg. dept. (Now referred as works dept.):

2. Materials are to be tested as per the procedures prescribed in this book.3. Tender samples of successful vendors are kept preserved till the supply of

entire quantity of material against the same is completed.4. Samples of unsuccessful vendors are asked back by MM dept.5. Materials from outside parties are tested for R & D purpose as chargeable

jobs under reference no. MTL-27.6. Samples are to be marked with IM / Tender nos. Etc. for identification.7. Aluminum solder and Plumbing metal are tested at outside laboratory as

presently chemical analysis is not feasible in our laboratory.

Flow of papers:

1. References are received and registered in the inward register byadministrative staff and then forwarded to respective officers.

2. Materials are checked and collected by testing staff/officers.3. DyEMTS distributes the works among testing officers/staffs.4. After testing materials within stipulated time reports are prepared in

duplicate by testing officers/staffs and scrutinized by DyEMTS.5. It is then verified by AEMTS and approved by DEMTS.6. Reports are then forwarded to respective accepting / requesting

authority.7. Duplicate copies are preserved in MTS dept. in respective files by

administrative staff.

DEMTS

6

BLACK ADHESIVE TAPE

1. Objective TESTING OF BLACK ADHESIVE TAPE

2. Apparatus/material

Micro-meter, Tensile machine , Spring balance, 0-5 KV HV Test SetSteel plate , roller etc.

3.Responsibility Testing is to be done by Minimum T-5 grade staff.

4. Reference IS 7809 (PART I & II): 1977 -Pressure Sensitive Adhesive Tapes for Electrical Purpose

SPECIFICATION NO. MTS/MTL-2/3/99 with latest amendments.Pressure sensitive Adhesive Tape with Woven water proof cottonbase, black insulating adhesion one side coated, shall meet thefollowing parameters:-

a) Thickness: 0.3 +/- 0.045 mmb) Width : 20 +/- 1.0 mmc) Roll length: 25 metersd) Tensile Strength: 8.0 Kg/cm widthe) Adhesion to steel: 150 grams/cm width (Before

ageing). 100 grams /cm width (After Ageing)f) Breakdown Voltage: 2.0 KV

5 Procedure 5.1 Sampling : ( As per IS – 8402-1977 )Upto 100 2101 to 500 5501 to 1000 71001 and above 105.2 Dimension analysis :

5.2.1 Thickness (Clause-3 of IS 7809 P-II) : Measurement5.2.1.1 Test Apparatus:

A dead weight dial type micrometer having two ground andlapped concentric circular surfaces, flat within 0.001 mm andparallel to within 0.003 mm shall be used. The dial shall begraduated to read correctly to 0.002 mm. The accuracy of themicrometer shall be checked frequently by means of a set of steelgauges. The measuring errors of the micrometer shall not exceed0.005 mm.

5.2.1.2 Test Specimen:Nine Specimens at least 75 mm long, are cut from the roll atintervals of not less than 300 mm.

5.2.1.3 Procedure:-Place the test specimen between the jaws of the micrometer withadhesive side down in contact with the fixed foot. Take care toensure that no air bubbles are trapped. Lower the moving pressure

7

foot gently into the surface of the tape and take the reading on thedial within two seconds. Make the measurements to the nearest0.005 mm.Report the centre value as well as the max. and min. values of thenine measurements of thickness in mm.

5.2.2 Width (Clause-6.2of IS 7809 P-I)When measured with scale it should be 20mm + 1mm.

5.3 Tensile Strength (Clause-9 IS 7809 P-II):5.3.1 Apparatus: A tensile testing machine, power driven equipped

with a continuous load indicating device, calibrated to determineeven one percent of the breaking load.

5.3.2 Test Specimens: Five test specimens of sufficient length to givean initial length of 200 mm are removed from the roll under test bypulling radially, at a rate of 300 mm per second, at intervals of300 mm.If the width of the tape is 25 mm or less, the width of the specimenis the width of the tape.

5.3.3 Procedure: Insert the test specimen into the machine so that theload is applied evenly across the width of the tape. For tapes

having an elongation at break up to 50 percent, the initial testlength is 200 mm. The test specimen is elongated until it breaks,with a uniform rate of movement of the driven jaw of 300 +/- 30mm per minute. The maximum load is recorded. Five validdeterminations are made. It is necessary to take care to ensure thatduring the test the tape does not slip in the jaws of the testingmachine.

5.3.4 Result:Report the tensile strength in Newton per 10 mm width for eachMillimeter thickness.

5.4 Adhesion to steel (Clause10 IS 7809 P-II ) :5.4.1 Apparatus: 5 Rectangular test plate of stainless steel of the

following composition.Carbon0.16 % max. Silicon 0.2 % min.Manganese 2.0% max. Nickel 8-14%Chromium 1-18 %

A convenient size of plate is 200 X 50 mm; the thickness shallbe at least 2 mm. The test surface of the plate shall be polished togive an abrasive satin finish.

8

Roller: A polished steel roller having a diameter of at least 50 mmand mass 2 Kg, being able to exert a pressure of 20 N per 10 mmwidth.

5.4.2 Test Specimen: Five strips of 450 mm length are removed fromthe roll under test by pulling radially, at a rate of 300 mm/s atinterval of 300 mm.

5.4.3 Procedure: The face of the plate is wiped with a fresh piece ofcotton wool saturated with pure toluene. The clean plate isallowed to dry and is then suspended above the liquid in a toluenevapour bath and allowed to remain for 5 minutes after the vapourline has reached the top of the plate.

On removal from the vapour bath, it is suspended forapproximately 30 minutes at 27 +/- 2oC & 65 +/- 2% RH

5.4.4 Preparation for the Adhesion to Steel Test:The prepared plate is placed with the test surface upwards on theedge of a bench. The test specimen is applied with the adhesivesurface downwards to the test surface of the plate parallel to thelonger sides of the plate. Take care that no air bubbles are trappedbetween the tape and the plate. Approximately 250 mm length ofthe test specimen overhangs downside. Place the roller centrallyacross the test specimen on one end of the plate and pass it by loadat a constant speed four times over the test specimen on the platestwice in each direction, so that each traverse of 200 mm takes 10 to12 seconds. The specimen shall be applied to the plate within 15seconds of being taken from the roll of tape. The overhang side isplaced in the traversing jaw of the tensile machine and the free endof the test specimen is placed in the other jaw. Care should betaken to ensure that the free tape is parallel in both planes to theapplied tape. The traverse jaw is set in motion at a rate of 300 +/-30 mm /minute and the readings at five consecutive 12.5 mm, 20mm or 30 mm interval marks are recorded. The test is performed at27 +/- 2oC and 65 +/- 2% relative humidity.Record the five readings on each of the five test specimen. Arrangethe five readings for each test specimen in ascending order and takethe central value of each group. Arrange the five centre values soobtained in ascending order and take the centre values of this as theadhesion to steel. Express the values in gm/cm.

5.5 Voltage Breakdown (Clause 7.1 IS 7809 P-II):The width of the tape to be used shall be in the range of 12 mm to

25 mm. The specimen of tapes to be tested are prepared bywrapping the tapes spirally around clean brass or copper rods of 8

9

mm diameter over a length of 200 mm with overlap slightly lessthan 50 percent. One end of the rod is left unwrapped and used formaking an electrical connection. A conductive paint or a metal foilat the centre portion of the test specimen will serve as one electrodehaving a length of 100 mm. AC voltage is applied through 0-5 KVHV Test Set. The voltage is raised at a nearly uniform rate of 100to 200v per second until breakdown occurs between 10 to 20seconds.

5.6 After ageing test ( only on tender samples):

The black adhesive tape ( 30 cm in length ) when tested after 2hours after ageing shall withstood the adhesion test as prescribed inpara 5.4 ,( Ageing : 2 specimen from each sample are kept suspended in dryair oven simultaneously at 80o+ 1oC for 120 hours. )

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10

COTTON TAPE

1. Objective TESTING OF COTTON TAPE


Dial gauge, Scale , Tensile machine, Electronic weighing machine


4. Reference IS NO :-1923 / 1973Specification :- Tender specification

5 Procedure 5.1 Sampling:

Upto 100 2101 to 500 5

501 to 1000 71001 and above 10

5.2: DIMENSIONAL ANALYSIS

Equipment :- Dial gauge, Scale.

5.2.1 THICKNESS OF TAPE (Table – 1 of 1923)

i) With the help of dial gauge measure the thickness.ii) Five measurements shall be made at random in a length not less

than 1 meter of tape. From each sample.iii) The average of these 5 measurements shall lie within the limits.

Specified in table 1 (+ 10%). Our specified value is 0.18 mm +0.018 (10%).

5.2.2 WIDTH(Table – 1 of 1923)

i) Width shall be measured at 5 places at random in a length not lessthan 1 meter of tape from each sample role.

ii) The width shall not vary by more than 1 mm from the specifiedvalue. Our specified value is 20 / 25 mm I 1 mm.

5.3 WEIGHT / 100 METERS IN GMS(Table – 1 of 1923)

i) Take a piece of 1 meter length.ii) Note down the weight on Electronic weighing machineiii) Covert this weight in weight / 100 meters by multiplying by 100.iv) Specified weight /100mtrs. for 20 mm width tape is 130 gms + 5%.v) Specified weight/100 mtrs. for 25 mm width tape is 165 gms + 5%.

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5.4 TENSILE STRENGTH

(Table – 1 of 1923)

Equipment – Tensile machine.

Cut the test sample from one roll of 30 cm in length & full width.

i) Adjust the constant speed of 30 cm / min.*ii) Adjust the length on the tensile machine to 20 cm (test length 20

cm)iii) Keep the range on 100 kgf.iv) Fix the sample piece in the jaws of the tensile machine.v) Press the “down” button on the Tensile machine & observe the

value on the tensile scale at which the tape specimen tears.vi) The tensile strength is express in kgf / full width.vii) Our specified value is (for 20 mm width tape) is 16 kgf & for 25

mm width tape is 20 kgf.*By adjusting the belt position respectively provided at the bottomon the bank side of the tensile machine.

Note :- The Sample piece of tape at the time of break should cut atthe centre only.


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12

HT BITUMEN TAPE

1. Objective Testing of HT Bitumen Tape

2. Apparatus/ material

0-5 kV H.V. Test set. 5 point HV Test Apparatus , scale , DialGauge, Tensile machine

3.Responsibility Testing is to be done by minimum T-5 grade staff.

4. Reference IS- 7755 / 1975 – Specification for High Tension InsulatingCotton Tape Impregnated with Bitumen- Based CompoundIS 2584-1963

5. Procedure 5.1 Sampling: ( Table 3 of IS 7755)Lot size Nos. of samplesUp to 25 226 to 50 351 to 100 5101 to 300 8301 and above 13

5.2: Dimensional Analysis (Clause 4.0 & 10.3)5.2.1 Width:

The width shall be measured at five places at random in a length ofnot less than one meter of tape from each sample roll & in no caseshall the width vary by more than one millimeter from the nominalwidth measure the width by steel rule.

5.2.2 Thickness:

The thickness shall be measured with a dial type micrometer. Fivemeasurements shall be made at random in a length of not less thanone meter of tape from each sample roll. The average of thesemeasurements (five) shall fall within the limits of 0.40 +/-0.05mm.

5.3 ELECTRIC BREAKDOWN STRENGTH (Cl. 3.4.4.1 ofIS)

Equipment: - 0-5 kV H. V. Test set, 5 point H. V. Testapparatus.

5.3.1 Take a 30cm length of sample piece & plate in the 5 point H.V. Test apparatus such that upper & lower electrodes areplaced at the centre of the tape width wise. Take care that noflashover takes place between the two electrodes.

5.3.2 Phase probe is connected to upper electrode & earthing probeis connected to the lower electrode.

13

5.3.3 Uniformly go on increasing the H.V. A.C voltage till theUp to 4KV. Set the timer for 1 minute. No failure shouldoccur during this period.

5.3.4 Repeat this procedure on all the reaming four points.

5.4 Breaking Strength in Kg / Cm Width (Clause 10.5)

5.4.1 Adjust the constant rate of traverse to 30cm / minute.5.4.2 Adjust the length on the tensile machine to 20cm.5.4.3 Keep the range of tensile testing machine to 100kgf.5.4.4 Tighten the test sample of 300mm length & 20mm width in

the jaws of the tensile machine. The initial distance betweenthe grip shall be adjusted to 200mm.

5.4.5 Press the “down” button of the tensile machine & observethe value on the tensile scale at the time, when the tapebreaks.

5.4.6 Express the value in kgf .Note: - Sample piece should cut at the centre only.

Specified value :- 20 kg /cm. (minimum)

5.5 Electrical strength test after ageing :(To be done only at tender stage)

The impregnated cotton tape ( 30 cm in length ) when testedwithin 3 minutes after exposure to dry air at 90o+ 1oC for 120hours, according to the method prescribed in IS-2584 shallwithstand 4KV for one minute without failure.

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14

IMPREGNATED PAPER SEPARATOR

1. Objective TESTING OF IMPREGNATED PAPER SEPARATOR


digital vernier caliper, oil test set, 0-5 kv. H.V. test, tensilemachine


4. Reference Spec : - MTS / STD – 29 / 09 / Rec. 1 dt. 21.08.02I.S. – 6792 : 1972I.S. – 10810 (PS) : 1964I.S. – 2584 : 1963

5. Procedure 5.1: Sampling : One sample per lot5.2: PHYSICAL OBSERVATION1) There should not be no. damage to the tin & also there should

not be any oil leakage from the tin .2) Open the tin & observe the oil level, if should be above the

level of paper.3) Count the no. of bundles in the tin . They should be 3 in No’s .4) Count the no. of small cotton tape rolls in tin . They should be

10 in No’s .5) Count the no. of papers in one bundle . They should be 35 in

no’s. minimum

5.3: DIMENSIONAL ANALYSIS OF PAPER( 3.3 to 3.4 )1) Measure the length the paper by digital vernier caliper . The

length should be 270 mm + 5 mm.2) Measure the width of the paper by digital minimum caliper.

The width should be 180 mm + 5 mm.3) Measure the thickness of the paper by digital vernier caliper .

The thickness should be 0.1 mm + 0.008 mm .

5.4: BREACK DOWN VALUE OF OIL (Electric strength) (CL . 7)1) Take out the oil testing pot from H.V. oil test set & rinse it

with the oil in the Tin.2) Adjust gap between the electrodes of pot to 2.5 + 1 mm .

Check it with the ‘’Go” & “No Go” gauge Fill the oil in the tinin the testing pot , 2cm. above the level the of the electrode inthe pot . Replace this pot (filled with oil) in the H.V. oil test set.

3) Allow the oil to settle down for at least 10 minuets .4) Keep the forward / reverse switch on forward .5) Start the machine supply & then H.V. supply voltage will

gradually increase across the electrode at a rate 2kv / second .The pointer of the voltmeter will remain steady at a breakdownvalue .

15

6) Note down this value . Then push the forward / reverse switchto reverse .

7) Wait for 1 minute . Then again throw the forward / reverseswitch to forward & start the H.V. supply . Note down thisvalue .

8) Take six breakdown value of the 1 minute interval .9) Average value of the six values should be more than 28kv to

pass through this test .

5.5: BREAKDOWN VALUE OF PAPER (cl. 4.2)

1) Cut the sample paper of size 20 cm in length & 20 mm inwidth .

2) Put this paper on 5 point H.V. test apparatus & put the upperelectrode on the paper at extreme & point . Lower 5 point aretreated as earth & upper electrode as phase electrode .

3) Apply the ac high voltage through the 0-5 kv. H.V. testgradually increase the ac high voltage till the breakdownoccurs . Note down this value .

4) Now move this upper electrode to next point & again notedown the breakdown value . Repeat this an all 5 points . Findthe average value of the all 5 values .

5) Divide this average value by the thickness of the paper to getthe value in kv / mm thickness . This value should be 30 kv /mm thickness (minimum) .

5.6: TENSILE STRENGTH OF PAPER (4.1)1) Cut the sample paper of size 27 cm on length & 15 mm in

width .2) Adjust the length on the tensile machine to 20 cm .3) Keep the range to 100 kgf .4) Tight the above sample piece in the jams of the tensile

machine.5) Press the down button of the tensile machine & observe the

value on the tensile scale at a time of break of the paper .6) Note down the value & express this value in Newton / mm

thickness of paper . (multiply of the value of the tensilemachine by 9.81 & divide this value by thickness of the paper )

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16

L.T.BITUMEN TAPE

1. Objective TESTING OF L.T.BITUMEN TAPE


5 kV H.V. Test set. Dial type micrometer, steel rule.Tensile machine, Multi cell Ageing Oven. Illuminated boxBrass rod of 25mm thickness


4. Reference IS 2448 (P-I) / 1963 – Specification for Adhesive InsulatingTapes for Electrical Purposes

5. Procedure 5.1 Sampling :5 sample per lot of ( upto ) 5000 rolls are to be randomly

selected for testing.5.2 Dimensional Analysis (Clause 4.2 & 4.3 of IS-2448)5.2.1 Equipment: Dial type micrometer, steel rule.Width:

The width shall be measured at five places at random in alength of not less than one meter of tape from each sampleroll & in no case shall the width vary by more than onemillimeter from the nominal width measure the width bysteel rule.

Thickness:The thickness shall be measured with a dial typemicrometer. Five measurements shall be made at random ina length of not less than one meter of tape from eachsample roll. The average of these measurements (five) shallfall within the limits of 0.40 +/- 0.05mm.

5.3 : Electrical Breakdown Strength (cl.6.1 & 10.9 of IS- 2448.)Equipment: - 0-5 kV H. V. Test set,

5.3.1 Suitable length of tape shall be taken from each sample rolland helically wound with 50% overlap for a distance of 150mm along a clean polished cylindrical brass electrod of 25mm dia..

5.3.2 The centre 50mm length of the wrapped tape shall then becovered with the metal foil held firmly in contact with thetape to form the outer electrode.

5.3.3 Voltage Uniformly increased to 1 KV in 1 minute. WhichShall be then maintain for a further 1 minute. No failureshould occur.

17

5.4 Breaking Strength in Kg / Cm Width (Clause 10.5 of IS-2448)5.4.1 Equipment: Tensile machine,

Adjust the constant rate of traverse to 30cm / minute.Adjust the length on the tensile machine to 20cm.Keep the range of tensile testing machine to 100kgf.Tighten the test sample of 300mm length & 20mm width inthe jaws of the tensile machine. The initial distance betweenthe grip shall be adjusted to 200mm.Press the “down” button of the tensile machine & observe thevalue on the tensile scale at the time, when the tape breaks.Express the value in kgf / cm width of tape.Note: - Sample piece should cut at the centre only.Specified value :- 7 kg /cm. (minimum)

5.5 Test of Pinholes(Clause 5.3 of IS-2448)Switch ON the illuminated box.Place a 3 meter test piece over the slot in the top of theilluminated box. The box shall be approximately200mm wide,200mm high & 450mm long internally & the slot shall be 50mm wide & 300mm long. The inside of the box shall bepainted white & illuminated by a 25W lamp & the slot shallbe covered with clear glass, set flush with the top of the box.Observe the no. of pin holes in the 3 meter length of the tape.No. of pin holes shall not exceed 15 for 20mm wide tape in 3meter length.

5.6 Adhesion Test before Ageing (Resistance to Stripping)(Clause 10.7.2 of IS-2448)

5.6.1 Test Apparatus:The test apparatus shall consist essentially of a rigidcylindrical mandrel of 25mm diameter mounted horizontallyon ball bearings; the length of the mandrel shall be sufficientto accommodated the full width of the tape & the bearingsshall be such that the mandrel turns freely under a weight of30 gm suspended by cotton thread wound in a single layerover the centre.

Weight – Different size of weight up to 3.35 kg250 gm weight hanger chalk,Stop watch, scale (1 meter)

5.6.2 Test Procedure:The adhesive properties of the tape before acceleratedageing shall be determined at a temperature of 27 +/- 2oC.

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A test length of one meter shall be taken from each sampleroll. Approximately, 15cm of the tape shall first beuniformly wound in superimposed layers on to the centre ofthe mandrel. A load of 1.8kg / cm of width shall then beapplied to the free end. The next 60 cm of the tape shall bewound on at a rate of 30cm/min & then the wound tape thenheld so loaded for three minutes. At the end of this time aweight of 0.70kg/cm width of tape shall be substituted forthe heavier load & the mandrel freed. Under theseconditions the tape shall unwind & after 100mm haveunwound, the length of the tape that unwinds in the nextminute shall be measured & recorded. This length shall notexceed 300mm.

5.7 Adhesion Test after Ageing (Resistance to Stripping)(Clause 10.7.2 of IS-2448)

5.7.1 Test Apparatus: 1) Multi cell Ageing Oven2) The test apparatus shall consist essentially of a rigidcylindrical mandrel of 25mm diameter mounted horizontallyon ball bearings; the length of the mandrel shall be sufficientto accommodated the full width of the tape & the bearingsshall be such that the mandrel turns freely under a weight of30 gm suspended by cotton thread wound in a single layerover the centre.Weight – Different size of weight up to 3.35 kg

250 gm weight hanger chalk,Stop watch, scale (1 meter)

5.7.2 Test Procedure:A specimen of tape similar to above shall be exposed to dryair at a temperature of 80+/-1oC for a period of 120 hours inthe multi cell oven. After a rest period of not less than twohours & not more than six hours at 27+/- 2oC (during whichperiod the aged specimens shall be protected from contactwith foreign matter), the specimen shall satisfy therequirement of the test described as above except that theweight applied to unwind the tape shall be 0.35 kg/cm ofwidth instead of 0.70kg/cm of width.

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19

PVC TAPE ( R,Y,B,N)1. Objective Testing of PVC Tape ( R,Y,B,N)


0-5 KV HV Test set, Tensile machine. Scale, dial gauge


4. Reference IS NO: - 13262 / 1992Specification: - Tender Specification.

5. Procedure 5.1 Sampling : As per IS - 8402Upto 100 2101 to 500 5501 to 1000 71001 and above 10

TEST CONDUCTED

1) Physical & Dimensional Analysis.2) Electric breakdown strength.3) Tensile strength & elongation.

5.4 : PHYSICAL AND DIMENSIONAL ANALYSIS5.2.1 Observe the colour of the tape whether of as per tenderspecification or not.

5.2.2 Thickness: - With the help of the dial gauge measure thethickness. Our specified value is minimum 0.15mm.

5.2.3 Width: - With the help of steel rule measure the width. Thetolerance as per clause 5.5 of 13262 is +/- 1.0mm. Our specified valueis 20mm.

5.3 : ELECTRIC BREAKDOWN STRENGTH (Tender Spec.)Equipment: - 0-5 kV H. V. Test set, 5 point H. V. Test apparatus.5.3.1 Take a 30cm length of sample piece & plate in the 5 pointH. V. Test apparatus such that upper & lower electrodes areplaced at the centre of the tape width wise. Take care that noflashover takes place between the two electrodes.

5.3.2 Phase probe is connected to upper electrode & earthing probe isconnected to the lower electrode.

5.3.3 Uniformly go on increasing the H.V. A.C voltage till thebreakdown occurs.

5.3.4 Note down the breakdown voltage.

20

5.3.5 Repeat this procedure on all the reaming four points.5.3.6 Calculate the average of the above 5 breakdown voltages &

divide it by the thickness of tape measured in mm , Thus we getbreakdown voltage per mm thickness of tape. Our specifiedvalue is 2.5 kv AC / mm thickness (minimum). (sp. No.M10140102)

5.4 : TENSILE STRENGTH AND ELONGATIONEquipment :- Tensile machine,5.4.1 Cut the test sample of 20cm in length & 20mm in width.5.4.2 Adjust the constant rate of ............... of 30cm / minute.5.4.3 Adjust the distance between the jaws of the tensile machine

to 12cm.5.4.4 Keep the range in 100 kgf.5.4.5 Clamp the sample piece in the jaws of the tensile machine.5.4.6 Adjust the belt position respectively provided at the bottom on

the back side of the tensile machine. Press the “down” button”of the tensile machine & observe the value on the tensile scaleat the time of break & also note the length at the break.

5.4.7 Express the tensile strength in N / cm width tape.Calculation: -

= Observed value on tensile scale in kgf x 9.81Width of tape in cm

5.4.8 Express the elongation at break in %.Calculation: -

= Final length – initial length x 100Initial length

Final length : - Length at break.Note: - Sample should break at the centre only.

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21

HRC FUSES

1. Objective TESTING PROCEDURE FOR HRC FUSES

2. Apparatus

/ material

Loading Transformer, Digital Thermometer, Conductivity meter,Scale, Multi meter, fuse base, cables, bus-bars etc.

3.Responsibility Testing is to be done by Minimum T-5 grade ( Testing Assistant )or Testing Engineer T8 grade.

4. Reference IS No. 13703 (Part I & II) , IS No. 9926 & BEST specification..

5. Procedure 5.1: Sampling: IS No. 9926 (Table-3) Cl.no. A-1.2 & A-2.1(To be selected randomly)

Upto 150 5

151 to 500 8

501 to 1000 13

1001 to 3000 20

3001 & above 32

TESTS:1. D.C. Resistance measurement.2. Temp. rise test ( at rated current)3. Non Fusing test (at 1.1 times rated current for 280 amps

&1.25 times rated current for all other HRC fuses)4. Fusing test ( at 1.4 times rated current for 280 amps. Fuse

and 1.6 times rated current for all other HRC fuses)5. Conductivity of blade contacts6. Dimension analysis ( as per data sheet of IS-13703-P II)

22

5.2 D.C. RESISTANCE MEASUREMENT TEST (Cl.No -8.1.5.1 of IS 13703 (Part-I) 1993

In most of the cases it is noticed that value of d.c.resistanceselected samples differ from one another (5% to 10%)hence it is advisable to connect 2 samples. one havingminimum d.c resistance & other having maximum d.cresistance to check characteristic of Non-fusing, Fusing test& watt loss. Before the tests are commenced the internalresistance ‘R’ of all the samples shall be measured at theambient air temperature of 20 ± 5°C with a measuringcurrent of not more than 0.1 In. The value ‘R’ shall berecorded in the test report.Note down the sample number of minimum & maximum‘R’ from selected samples to measure watt loss,temperature rise test, non fusing & fusing test.

5.3: TEMPERATURE RISE TEST (Cl .no.7.3 of IS-13703-1.)Equipment / accessories :- Single phase Loadingtransformer Milivolt meter (multi meter with mV range),cables / bus bar of proper sizes, Spanners, Screwdrivers,torque wrench , tong tester .

5.3.1 Connect the Porcelain fuse bases to loading transformerwith the appropriate size of copper cable / bus bars of twometers length as per IS-13703 table-10. Tight the nut-boltswith the help of torque wrench. Insert the fuses (minimum& maximum D.C.Resistance) & ensure the contactresistance by measuring milivolt drop at nut-bolt (betweenbus bar & fuse base terminal) at a rated current should bewell within 10 mV.

5.3.2 Switch on the Loading transformer. Gradually increase thecurrent by controlling coarse and fine adjustment ofLoading transformer to the rated current. Confirm the samewith tong tester.

5.3.3 Maintain rated current for 4 hours or till the temperaturereading get stable.Measure the temperature at following points after 4 hrs.a) The fuse base & the fuse contactb) In the fixed terminal of the base

5.3.4 Also measure mili volt drop across fuse link with the help ofMulti-meter and multiply it by the rated current to obtain thewatt loss. It should not exceed the values given in clause ofBEST specs.

23

5.4 NON FUSING / FUSING TEST: (BEST specification) /clause No. 5.6.2 of IS 13703 (Part-I) Table-2.

Non fusing and fusing tests being destructive in nature areperformed only on two samples which are tested for d.cresistance , having maximum & minimum d.c resistance andtested for temperature rise & watt loss measurement.

NOTE: Tests are to performed with vertically mounted fusebase assembly.

5.4.1 Connect the HRC fuse bases to the loading transformer withthe appropriate size of copper cable / bus bars of two meterslength mentioned in IS. Insert selected fuse one at a time inthe bases.

5.4.2 Start the Loading transformer. Gradually increase the currentcontrolling coarse and fine adjustment of loadingtransformer to the current as prescribed in the table 2 of IS13703 part I or BEST specification.Confirm the same with tong tester. Note down the timing.The fuse should not blow within specified time period.

5.4.3 Allow the fuse under test to cool down to ambienttemperature & thereafter subject to the fusing current (If)test, fuse should blow within specified time period.

5.5 CONDUCTIVITY OF HRC FUSES BLADE CONTACTS(As per tender specification)

5.5.1 Make the corrugated surface of blade contact plain &smooth.

5.5.2 Clean the surface of the blade contact of fuse under test withbenzene. Keep the test pieces along with the standardsamples (Known conductivity plates) & equipment for atleast 1 hour for the equalization of temperature so that thereshall be no need to apply any temperature correction to theconductivity value obtained in % IACS.

Switch ‘ON’ the conductivity Meter & keep it in ‘ON’position for at least 20 minute for warm up.

24

After 20 minute of warm up time calibrate the conductivitymeter with known conductivity plates (provided withequipment) by placing the conductivity probe on these plates.One plate is of 22% of IACS conductivity & another is99.5% of IACS conductivity. While calibration theconductivity meter with lower conductivity plate (22% ofIACS) if the displayed reading is not 22% then adjust it to22% by adjusting the low range adjustment knob on theconductivity meter. Similarly while calibrating theconductivity meter with higher conductivity plate (99.5 % ofIACS). if the displayed reading is not 99.5% then adjust it to99.5% by adjusting the high range adjustment knob on theconductivity meter. Confirm the calibration of theconductivity meter for at least 4-5 times without adjustingany knob.Now place the conductivity probe on the surface of thecontact under test & ensure that there is a proper contactbetween the conductivity probe & the test piece surface. Notedown the reading. Take the readings at 4-5 different places &the best one shall be reported.

5.6: DIMENSIONAL ANALYSIS AS PER DRAWING

Measure the dimensions as per the data sheet of IS 13703 partII. Also observe the coating material of blade contacts byvisual inspection. It should be silver plated.

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CUT OUTS1. Objective Testing of Cutouts

2. Apparatus

/ material

0-5 KV HV Test Set , 500 V Megger ,Loading Transformer, DigitalThermometer, Scale, Multi meter, fuses , cables etc.


4. Reference IS No. 2086/1993

BEST specification/ Drawing

5. Procedure 5.1 : Sampling : ( To be selected randomly )Acceptance 1st

Rejection

2nd

Rejection

1st

stage

2nd

stage

Cumulative Number Number Number

n n 2n C1 C2 C3(1) (2) (3) (4) (5) (6) (7)

Upto150

5 5 10 0 2 2

151 to500

8 8 16 0 2 2

501 to1000

13 13 26 0 2 2

1001 to3000

20 20 40 0 3 4

3001and

above

32 32 64 1 4 5

TESTS To be conducted:1. HV Test ( 2KV AC for 1 minute)2. IR Test (should be more than 50MΩ3. Temp. rise Test ( at rated current)4. Dimension analysis ( as per BEST approved drawings)

5.2 : HV Test:All randomly selected sample should withstood 2KV AC for1minute between current carrying part and metal body, whentested with 0-5 KV HV Test Set.Connect one terminal of test set with current carrying part of cut

26

out and another terminal with earthing terminal on body. SwitchON the set and increase voltage gradually to 2KV. Set the timerfor 1 minute( 60 seconds). Set should not trip within 1 minute( 60seconds).Repeat the test with all the randomly selected samples.

5.3 IR Test :When tested with 500 volt megger all samples should haveinsulation above 50MΩ.

5.4 : TEMPERATURE RISE TEST(cl . 5.4 of spec.)

Equipment / accessories :- Single phase loading transformermilivolt meter (multi meter with mv range) thermocouplethermometer , cables / bus bar of proper sizes, Spanners,Screwdrivers, torque wrench , tong tester .

5.4.1 Connect the cut outs to loading transformer with theappropriate size of cables of two meters length. Tight the nut-bolts with the help of torque wrench. Insert appropriate size offuse wire / fuse link in cut outs. Connections should be such thatmilli volt drop at nut-bolt at a rated current should be wellwithin 10 mv.

5.4.2 Start the Loading transformer . Gradually increase the current byvarying respective variac of loading transformer ) to the ratedcurrent . Confirm the same with tong tester. Maintain this current& after 4 hours. Measure the temperature at the link contact

5.5 : DIMENSIONAL ANALYSIS AS PER DRAWING

Measure the dimensions as per the respective BEST approveddrawings. Also observe the coating material of link by visualinspection. It should be plated.

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FUSE BASES

1. Objective TESTING PROCEDURE FOR FUSE BASE OF VARIOUS SIZES

2. Apparatus

/ material

0-5 KV HV Test Set, Loading Transformer, Digital Thermo-coupleThermometer, Scale, Multi meter, 500 V Megger , links / fuses ofcorresponding size , bus bars / cables of different sizes etc.


4. Reference IS NO. 2086/1993, 13703 ( PART I & II )BEST Specification/ Drawing

5. Procedure 5.1 : Sampling : ( Table 2 IS NO. 2086/1993)

1st

stage2nd

stageCumulative Acceptance

Number1st

RejectionNumber

2nd

RejectionNumber

n n 2n C1 C2 C3(1) (2) (3) (4) (5) (6) (7)

Upto150

5 5 10 0 2 2

151to

500

8 8 16 0 2 2

501to

1000

13 13 26 0 2 2

1001to

3000

20 20 40 0 3 4

3001and

above

32 32 64 1 4 5

5.2 : HV Test:This test is to be performed in HV test lab with 0-5 KV HVtest set. Connect HV terminal of test set with current carryingpart of fuse base and another terminal with reference plate onwhich fuse base is kept. Switch ON the set and increase voltagegradually to 2.5KV. Set the timer for 1 minute( 60 seconds). Setshould not trip within 1 minute( 60 seconds).Repeat the test with all the randomly selected samples.

5.3 IR Test :When tested with 500 volt megger all samples should haveinsulation above 50MΩ.

28

5.4: TEMPERATURE RISE TEST(cl . 5 of spec.)

Equipment / accessories :- Single phase loadingtransformer milivolt meter (multi meter with mv

range), Digital Thermo-couple Thermometer,cables / bus bar ofproper sizes, Spanners , Screwdrivers, torque wrench , tong tester .

5.4.1 Connect the fuse bases with the aluminum bus bars / cables ( ofappropriate current carrying capacity ) of two meters length. Tightthe nut-bolts with the help of torque wrench. Connections shouldbe such that milivolt drop at nut-bolt between bus bar & fuse baseterminal ) at a rated current should be well within 10 mv.

5.4.2 Start the Loading transformer . Gradually increase thecurrent by coarse and fine tuning of loading transformer ) to therated current. Confirm the same with tong tester .

5.4.3 Maintain this current constant till the link & fuse base terminalattain steady state temperature. When the temperature does notchange more than 1oC in 1 hour, the steady state is reached.

5.4.4 We generally measure the temperature rise after 4 hours.

5.4.5 Measure the temperature at:

a) The fuse base & the link contactb) In the fixed terminal of the base

The temperature rise measured shall not exceed the definedvalues.

5.5 : CONDUCTIVITY OF CONTACTS(cl. 2 of spec. & table 4 of IS 1897 : 1983)

Clean the surface of the contact under test with benzene, and keepthe test pieces along with the standard samples (Knownconductivity plates) & equipment for at least 1 hour for theequalization of temperature. Hence, there shall be no need to applyany temperature correction to the conductivity value obtained in %1ACS.

Switch ‘ON’ the conductivity Meter & keep it in ‘ON’ positionfor at least 20 minute for warm up.

After 20 minute of warm up time calibrate the conductivity meterwith known conductivity plates (provided with equipment) byplacing the conductivity probe on these plates. One plate is of 22%of IACS conductivity & another is 99.5% of 1 ACS conductivity.While calibration the conductivity meter with lower conductivityplate (22% of 1 ACS) If the displayed reading is not 22% then

29

adjust it to 22% by adjusting the low range adjustment knob on theconductivity meter similarly. While calibrating the conductivitymeter with higher conductivity plate (99.5 % of 1ACS) of thedisplayed reading is not 99.5% then adjust it to 99.5% by adjustingthe high range adjustment knob on the conductivity meter. Confirmthe calibration of the conductivity meter for at least 4-5 timeswithout adjusting any knob.

Now place the conductivity probe on the surface of the contact undertest & ensure that there is a proper contact between the conductivityprobe & the test piece surface & note down the reading. Take thereadings at 4-5 places & the best one shall be reported.

Conductivity should not be less than 99.25%

5.6 : DIMENSIONAL ANALYSIS AS PER DRAWINGMeasure the dimensions as per the latest approved drawing. Alsocheck for surface of contacts . They should be silver plated. Rating& manufactures name should be checked as per tender specification.

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NON - FUSIBLE COPPER LINK

1. Objective TESTING PROCEDURE FOR NON - FUSIBLE COPPER LINK

2. Apparatus

/ material

Loading Transformer, Digital Thermometer, Scale, Weighingbalance, Multi meter, conductivity meter


4. Reference Specification No: - 295330101Drg. No: - ES / PL / A : - 332 Rev .’F’/latest(cl. 2 of spec. & table 4 of IS 1897 : 1983)

5. Procedure 5.1 : Sampling :Acceptance 1st

Rejection2nd

Rejection1st

stage2nd

stageCumulative Number Number Number

n n 2n C1 C2 C3(1) (2) (3) (4) (5) (6) (7)Upto150

5 5 10 0 2 2

151to500

8 8 16 0 2 2

501to1000

13 13 26 0 2 2

1001to3000

20 20 40 0 3 4

3001andabove

32 32 64 1 4 5

5.2 : TEMPERATURE RISE TEST(cl . 5 of spec.)

Equipment / accessories :- Single phase autotransformermilivolt meter (multi meter with mv range), cables / bus bar ofproper sizes, Spanners ,Screwdrivers, torque wrench , tongtester .

31

5.2.1 Connect the 630 A HRC fuse bases with the two numbers of40 x 10 mm2 aluminum bus bars of two meters length. Tightthe nut-bolts with the help of torque wrench. Connectorsshould be such that milivolt drop at nut-bolt. Connectors( between bus bar & fuse base terminal ) at a current of 630should be well within 10 mv.

5.2.2 Start the Loading transformer . Gradually increase thecurrent by coarse and fine tuning of loading transformer ) tothe current of 630 ampere.

5.2.2 Maintain this current constant till the link & fuse base terminalattain steady state temperature. When the temperature does notchange more than 1oC in 1 hour, the steady state is reached.

5.2.3 We generally measure the temperature rise after 4 hours.5.2.4 Measure the temperature at:

a) The fuse base & the link contactb) In the fixed terminal of the baseThe temperature rise link measured shall not exceed 50oC

ambient condition of the temperature & humidity .

5.3 : CONDUCTIVITY OF LINK(cl. 4 of spec. & table 4 of IS 1897 : 1983)

5.3.1 Make the corrugated surface of the link (of end) plain &smooth .

Clean the surface of the contact under test with benzene, andkeep the test pieces along with the standard samples (Knownconductivity plates) & equipment for at least 1 hour for theequalization of temperature. Hence, there shall be no need toapply any temperature correction to the conductivity valueobtained in % 1ACS.

5.3.2 Switch ‘ON’ the conductivity Meter & keep it in ‘ON’ positionfor at least 20 minute for warm up.

5.3.3 After 20 minute of warm up time calibrate the conductivitymeter with known conductivity plates (provided withequipment) by placing the conductivity probe on these plates.One plate is of 22% of IACS conductivity & another is 99.5%of 1 ACS conductivity. While calibration the conductivitymeter with lower conductivity plate (22% of 1 ACS) If thedisplayed reading is not 22% then adjust it to 22% by adjustingthe low range adjustment knob on the conductivity metersimilarly. While calibrating the conductivity meter with higherconductivity plate (99.5 % of 1ACS) of the displayed readingis not 99.5% then adjust it to 99.5% by adjusting the high rangeadjustment knob on the conductivity meter. Confirm thecalibration of the conductivity meter for at least 4-5 timeswithout adjusting any knob.

32

5.3.4 Now place the conductivity probe on the surface of thecontact under test & ensure that there is a proper contactbetween the conductivity probe & the test piece surface & notedown the reading. Take the readings at 4-5 places & the bestone shall be reported.

Conductivity should not be less than 99.25%

5.4 : DIMENSIONAL ANALYSIS AS PER DRAWINGDrg. No. ES / PL / A – 33 Rev. ‘F’ Dated – 09/08/2001 .

Measure the dimensions as per the drawing. Also check forsurface of link. It should be corrugated. Also observe thecoating material by visual inspection. It should be silver plated.Rating & manufactures name should be embossed at suitableplace on link.

5.5 Weight:Weigh the link in 30kg. weighting balance. Weight of the link should

not be less than 300gms.


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NEUTRAL LINKS

1. Objective TESTING PROCEDURE FOR NEUTRAL LINKS


0-5 KV HV Test Set , 500 V Megger ,Loading Transformer, DigitalThermometer, Scale, Multi meter, cables etc.


4. Reference IS No. 2086/1993BEST specification/ Drawing

5. Procedure 5.1 : Sampling : ( To be selected randomly )

1st

stage2nd

stageCumulative Acceptance

Number1st

RejectionNumber

2nd

RejectionNumber

n n 2n C1 C2 C3(1) (2) (3) (4) (5) (6) (7)

Upto150

5 5 10 0 2 2

151to

5008 8 16 0 2 2

501to

100013 13 26 0 2 2

1001to

300020 20 40 0 3 4

3001and

above32 32 64 1 4 5

TESTS:1. HV Test ( 2KV AC for 1 minute)2. IR Test (should be more than 50MΩ3. Temp. rise Test ( at rated current)4. Dimension analysis ( as per approved drawings)

5.2 : HV Test: Cl. 5.1 of specs.All randomly selected sample should withstood 2KV AC for 1minute when tested with 0-5 KV HV Test Set.This test is to be performed in HV test lab with 0-5 KV HVtest set. Connect one terminal of test set with current carryingpart of neutral link and another terminal with earthingterminal of the link on body. Switch ON the set and increasevoltage gradually to 2KV. Set the timer for 1 minute ( 60seconds). Set should not trip within 1 minute (60 seconds).

34

Repeat the test with all the randomly selected samples.

5.3 IR Test : Cl. 5.2 of specsWhen tested with 500 volt megger all samples should haveinsulation above 50MΩ.

5.4 : TEMPERATURE RISE TEST(cl . 5.3 of spec.)

Equipment / accessories :- Single phase loading transformer,milivolt meter (multi meter with mv range), cables / bus bar ofproper sizes, Spanners ,Screwdrivers, torque wrench , tong tester .

5.4.1 Connect the Neutral Links to loading transformer with theappropriate size of cable of two meters length. Tight the nut-boltswith the help of torque wrench. Connections should be such thatmilivolt drop at nut-bolt at a rated current should be well within10 mv.

5.4.2 Start the Loading transformer . Gradually increase thecurrent with coarse and fine tuning of loadingtransformer) to the rated current . Confirm the samewith tong tester. Maintain this current & after 4 hours.Measure the temperature at the link surface.

5.5 : DIMENSIONAL ANALYSIS AS PER DRAWINGMeasure the dimensions as per the respective approved drawings.Also observe the coating material of link by visual inspection. Itshould be tin plated.


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T.L. FUSES

1. Objective TESTING OF T.L. FUSES

2. Apparatus/ material Loading Transformer, Vernier Caliper , 1 sq. mm wire etc.


4. Reference IS 9926 / 1981, IS 8130 / 1984, IS 13703 / 1993 ,BEST Specification

5. Procedure 5.1 : Sampling: 2 samples per lot.

5.2: VISUAL EXAMINATIONRef: Clause 3.3 of spec.

1) There shall be no damage to the glass tube.2) Rating of the fuse shall be clearly embossed.3) Manufacture’s name shall be clearly visible.4) The fuse shall be provided with in built resin / hand paper

handle for taking out the blown fuses from the socket.5) Caps provided at all ends of cylindrical glass tube shall be of

brass.

5.3 : DIMENSIONAL CHECK

1) Check the diameter & length cylindrical glass tube, values isgenerally specified in Tender specification.

2) Check the length of the brass cap, which should be as perTender specification.

5.4 : NON FUSING TEST ( As per BEST specification)

1) Connect the T.L. Fuse socket with 1 sq. mm copper flexiblewire & connect these wires across the bus bars of single phaseloading transformer.

2) Switch ON the loading transformer & set the current at 1.2times the rated current of T.L fuses, by varying the variac ofsingle phase loading transformer.

3) The T.L fuse should not blow within half an hour .

36

5.5 : FUSING TEST ( As per BEST specification)

1) This test is to be immediately followed by the non-fusing test.2) Connect the T.L. Fuse socket with 1 sq. mm copper flexible

wire & connect these wires across the bus bars of single phaseloading transformer .

3) Switch ON the loading transformer & set the current at 1.4times the rated current of T.L fuses, by varying the variac ofsingle phase loading transformer.

4) The T.L fuse should blow within half an hour (i.e. 30 minutes).

5.6 : RESISTANCE OF WIRE IN Ohms / m at 20oCRef: Table 1 of IS 9926: 1981

1) Value is not specified for 5 A rating.


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HPSV LAMP

1. Objective Testing of HPSV Lamp


Lamp ageing panel ,Digital Lighting Panel, Illuminating Sphere,Reference Ballast, Ordinary ballast, ignitor , Kelvin holders , LuxMeter, Variac , lead wire etc.


4. Reference IS 9974 : 1981 RA 1992, BEST Specification SLC / 203/2008With latest revisions

5. Procedure 5.1 Sampling: 8 randomly selected lamps per lot. : 6 nos. fortesting electrical characteristic & 2 nos. for physical examination.

5.2 : Ageing of lamps6 ( six ) lamps selected for electrical characteristic are kept “ON”for 100 hours on ‘Lamp ageing panel’ then only are taken forfurther testing.

5.3 Electrical characteristic:( Lamp data sheet of IS 9974part II)5.3.1 Connect one lamp from 6 lamps selected for testing ofelectrical characteristic in the illuminating sphere with help ofKelvin holder. Select reference ballast ,ordinary ballast, ignitor asper the lamp wattage. 5.3.2 Arrange the circuit as shown on DigitalLighting Panel along with variac . Switch on the Digital LightingPanel. Keep it ON for atleast 20 minutes.

5.3.3 Gradually increase the voltage upto 198 volts. Touch theyellow wire of ignitor to 220 v terminal of ordinary ballast. Duringthis period the selector switch should be in position ‘1 ‘ . Lampshould ignite within specified time. Put the selector switch shouldin position ‘2’so that reference ballast will come in circuit.

5.3.4 Note the time taken to reach 50 V across lamp.

5.3.5 Increase the voltage to 220 Volts using frequency correctedchart.Measure all the parameters once readings get stabilized.

5.4 Measurement of Lumen Out put(This is to be done in continuation of above test )

5.4.1 With the help of Lux Meter measure the lumen output. Takeat least 5 readings and take average to avoid error.Lumen = Lux meter rdg. X constant of ref. lamp*

38

Gradually reduce the voltage and switch OFF the supply.Test all 6 lamps same way.

*Constant of reference lamp:

We have got lamps of different sizes calibrated from NPL NewDelhi. Each lamp is having specified lumen output. Verify thislumen at the time of testing and define a constant by dividingthe specified value by actual Lux meter reading obtained at thetime of testing. Take this constant for calculation purpose.

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LANTERN

1. Objective Testing of Lantern


500V megger, Thermo coal balls, Measuring Jar, 0-5 KV HV TestSet


4. Reference IS 10322 part 5, sec 3 & IS 1569/1975Specification no. SL/204A with latest revision.

5. Procedure 5.1 Sampling: As per IS 10322 (p5/sec1)-1985

For Visual examination,Insulation resistance & For otherelectrical Strength Acceptance Test

Samplesize

AcceptanceNos.

Samplesize

AcceptanceNos.

Upto150

8 0 2 0

151 to300

13 0 3 0

301 to500

20 1 5 0

501 to1000

32 2 8 0

1001 to3000

50 3 13 1

5.4 IR Test on Lantern As per Cl. 13.6 of IS 10322Shorten the both lead wires of the lantern. With the help of 500Vmegger check the insulation between the shortened wires andearthing terminal of the lantern. It should be more than 2 M Ω.

5.3 HV test on Lantern ( As per Cl. 13.6 of IS10322)Apply 1.5 KV between shortened lead wire and earthingterminal for 1minute. No flashover or discharge should beobserved.

5.4 IR Test on Capacitor ( Cl. 5.12.4.1 of IS 1569)Procedure is same as defined in the chapter of ‘capacitor forLantern’

40

5.5 HV test on Capacitor of IS 1569Procedure is same as defined in the chapter of ‘capacitor forLantern’

5.6 Measurement of Capacitance ValueProcedure is same as defined in chapter ‘capacitor forLantern’

5.7 Testing of Ignitor : Procedure defined in Chapter of‘IGNITOR’ is to be followed.

5.8 Measurement of volume of Lamp compartment andacrylic coverFill the cover with thermo-coal balls. Measure the volumeof thermo-coal balls in a measuring jar.Similarly measure the volume of Lamp compartment.

5.9 Measurement of bore diameter for pole fitting with the helpof vernier caliper. ( clause no. 2.1.1 of tender specification)

N.B. : When received against D/L from building ( works ) dept.lanterns consist of ballasts as well. In such cases ballasts are also tobe tested as defined in the chapter of ‘ BALLAST FOR HPSVLAMP’.

NIGHT Illumination Test is to be done on tender sample atAnik Yard as per next chapter.

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BALLAST FOR HPSV LAMP1. Objective TESTING OF BALLAST FOR HPSV lamps

2. Apparatus

/ material

0-5 KV HV Test Set , 500V Megger, Reference ballast, Standardlamp, Integrating Sphere, ThermometerDigital Lighting Panel and Variac, Ohm-meter


4. Reference IS-6616/1982BEST specification SL/213/HPSV Ballast

5. Procedure 5.1 Sampling: 10 samples per lot ( as per MTS ).

Tests to be carried out:

1. Visual Examination [Clause 9.4]2. Insulation Resistance Test [Clause 9.6.3]3. High Voltage Test [Clause 9.6.4]4. Test for Power and Current output [Clause 9.7]5. Temperature rise test [Clause 9.12]6. Physical dimension ( At tender stage only )

As per drawing no 213.

5.2 Visual Examination [9.4]:-Visual examination of the Ballast should not revealany damage to the ballast.

5.3 Insulation Resistance Test [9.6.3]:-The insulation resistance between live parts ofdifferent polarity and between live parts & externalparts shall not be less than 2 M Ohm.

5.4 High Voltage Test [Clause 9.6.4]:-The A.C. Test voltage i.e. 2.0 KV, for working voltageupto and including 250 V is applied between liveparts and all external metal parts for one minute.

Result:- No flashover or breakdown shall occurduring the test.

5.5 Test for Power and Current output [9.7]:-Requirements:-a. Reference ballastb. Standard lampc. VAW Panel and Variac

42

5.5.1. Connect reference ballast & standard lamp with theDigital Lighting panel.

5.5.2. Apply frequency corrected rated voltage to thereference ballast. Keep it on for sufficient time forsteady output of current & Power.

5.5.3 Note down the current & power across the lamp,ballast & total power and voltage across lamp &ballast.

5.5.4 Apply frequency corrected 92% and then 106% ofrated voltage and wait for constant values.

5.5.5 Note down the Power across lamp at 92% and 106%of rated voltage.

5.5.6 Now switch over to the ballast under test using thesame standard lamp and repeat the steps 5.5.2 tostep 5.5.5.

Calculation and Results:-

a. The power across the lamp at rated voltage shallnot be less than 92.5% of the power measuredwith the reference ballast.

b. The normal current at rated voltage shall not bemore than 115% of the current through the lampmeasured with the reference ballast.

c. The power across the lamp at 92% of rated voltageshall not be less than 88% of power measuredwith the reference ballast at 92% of rated voltage.

d. The power across the lamp at 106% of ratedvoltage shall not be more than 109% of powermeasured with the reference ballast at 106% ofrated voltage.

e. Measure the lumen output with reference ballastas well as with ballast under test.

f. Put all the result in tabular form as prescribedin the standard Test Report Format.

43

5.6 : Temperature Rise Test [9.12]

5.6.1 Measure the cold resistance of ballast at ambienttemperature (R1) with ohm-meter.

5.6.2 Connect the ballast with am-meter in series withvariac across 240 volt supply.

5.6.3 Increase the current upto the current of Ballastobtained at 264 volts during measurement ofelectrical characteristic. And maintain the same for 4hours.

5.6.4 After 4 hours switch off the circuit and immediatelymeasure the hot resistance with the help of Ohm-meter.(R2)

Temperatures are measured on windings by theresistance method, using the formula.

Max. Temp. = R2 [234.5 + Rt.] – 234.5 °CR1

Where, R1= Resistance of winding before heating.

R2= Resistance of winding after heating atabnormal current measured in stage 6, aor b whatever is applicable for 4 hours.

Rt = Room Temp. in oC.


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POTENTIAL TRANSFORMER ( 11KV / 110V, 33KV/110)

1. Objective TESTING OF PT/ VT ( 11KV / 110V, 33KV/110)


HV Test set ( 0-5 KV, 0-30 KV, 0-50 KV ), ScaleELTEL make CTVT test set, with source PT and Standard PT.

3.Responsibility Testing is to be done by Minimum T-8 grade Officer.

4. Reference IS No.:- 3156 (part 1 to part 4) / 1992

5. Procedure5.1 Sampling : 100% Testing to be done

5.2 PHYSICAL INSPECTIONi) There shall be no damage to body, primary bushings, secondary

terminals.ii) Polarity & terminals in each phase shall be marked.ii) Name plate of the potential transformer shall containfollowing information.a) The manufactures name & country of origin.b) Year of manufacture.c) Serial no.& type designation.d) The rated primary & secondary voltages.e) Rated frequency & rated voltage.f) Rated output & the corresponding accuracy class.g) Highest system voltage.h) Rated insulation level.i) Rated voltage factor & corresponding rated time.j) No. of phase & method of connection.k) Earthed or unearthed.l) Connection diagram.m) Reference standard.

All the information shall be marked in an indelible manner inthe voltage transformer itself or in a rating plate securelyattached to the transformer.

5.3 H.V.TEST ON PRIMARY WINDING(cl. 9.3 of 3156 (P.1)

A) Unearthed Voltage Transformers(cl. 9.3.1 of 3156 (P.1) )

5.3.1 Test voltage as per table 1A or table 1B shall be applied forone minute between all the terminals of the primary windingconnected together & the terminals of the secondary winding(connected together) and earth.

45

5.3.2 The frame case (if any), core (if intended to be earthed ) &all terminals of the secondary windings shall be connectedtogether & earthed. The voltage shall be increased at a rate2% per second.

RATED VOLTAGE (kv) TEST VOLTAGE (kv)11 kv 28 kv33kv 70 kv

Precaution :- Confirm that P.T. Fuses are present on all 3 phases.

B) EARTHED VOLTAGE TRANSFORMERcl. 9.3.2 of 3156 (P.1)

A test voltage of 3 kv rms shall be applied for one minutebetween the terminals of the primary winding intended to beearthed & earth. The frame case (if any) core ( if intended tobe earthed) & all the terminals of the secondary windingshall be connected together & earthed. There shall be nodisruptive discharge.

5.4 : H.V.TEST ON SECONDARY WINDING(cl. 9.4 of 3156 (P.1) )Equipment ;- 0-5 kv H.V. test set.5.4.1 The test voltage of 3kv (rms) shall be applied for one

minute between all the terminals of the secondary winding(connected together ) & the frame case (if any) , core(intended to be earthed ) & all terminals of the primarywinding shall have been connected together & earthed.There shall be no disruptive discharge.

5.5 : ACCURACY TEST

For 11KV / 110 V three phase P.T. accuracy test for ratio andphase angle error is to be done on ELTEL make CTVT test set.

Procedure for tesing VT or PT

Make the back panel connections as shown in Fig. 1. The STD VTsecondary terminals are to be connected to the STD terminals onthe back panel. Connect the desired burden across the Test VTterminals. Switch on the AITTS-98 test set and other relatedequipments. From the AITTS-98 main menu, press any key. Thiswill display the first menu. Now press ‘3’- which is the selectionmenu to enter all the parameters as desired.

46

In the selection menu enter-‘1’- here you can choose either % orabsolute value by again pressing ‘1’.

Enter ‘1’- to select voltage transformer test.

Enter’2’- do you wish to view the ratio error in % or in ppm? Bypressing ‘2’, the cursor can be shifted to select either % or ppm.

Enter ‘3’- do you wish to view the phase error in min or in rad?Press ‘3’ to choose either parameter.

Enter ‘4’- do you wish to have the accuracy class printed as perANSI, IEC, IEC-S, IS-P, IS-PR, AS-ME, BS or BS-S. Chooseappropriate digit to select the same.

Enter ‘6’- for selecting rated secondary voltage test VT.

Now this completes the selections of the menu. Now by pressing‘ENTER’all the above details will be retained in memory and thedisplay will return to the first menu.

To enter the customer specification, press’5’. This will display thecustomer settings screen.

Press-‘1’- the serial number of the test VT can be entered. A totalof 9 digits can be entered.

Press-‘2’- the burden value can be entered. 10 digits can beentered.

Now press ‘3’- the ratio of the test VT can be entered. Upto 6digits for the primary value and 5 digits for the secondary value canbe entered.

Option ‘4’- the testing date will be displayed in DD/MM/YYYYformat.

Press-‘5’- either to activate or deactivate auto print facility.

Press-‘6’- to select short or regular print formats.

After completing this menu, press ‘ENTER’ to retain the above

47

values in memory. A long beep will occur. After pressing‘ENTER’, the display returns to the first menu. This nowcompletes the panel entries for the AITTS-98.

Now form the first menu, press ‘1’ to go to the voltage transformermenu.

Increase the voltage to the test and STD VTs. Observe the frontpanel to check the voltage value. Raise the voltage to 120% ofrated value (either in value or in%). Note down the ratio error andphase error readings.

Bring down the voltage to 100% of rated value and take thereadings of ratio and phase errors.

For printing the test results, press F3. This prints the test results tothe printer.

Procedure for testing 3- phase Potential Transformer

The combined CT/PT metering set will have 3 phases namely“A,B,C” of primary and “a,b,c,n” of secondary. At any point oftime testing will be done between two phases namely ‘A-B’, or ‘B-C’ or ‘C-A’. Since it is a three phase PT, all the three phasesshould be excited and all the three phases should be located withthe rated burden to get the correct results. However, measurementwill be done between two phases simultaneously. The connectiondiagram for testing 3-phase PT is as shown in fig.2.

Further Details for using CT/PT Test set is in given in EQP-132file.

5.6: RATIO TESTFOR 33KV P.T.Ratio test in generally carried out in meter testing room.100 V is applied to primary winding ( phase voltage) andvoltages in the secondary terminals are measure. Ratio isconfirmed by the comparing primary & secondary voltages.

48

Method :5.6.1 Switch ‘ON’ the control panel & voltage circuit MCB ( one

MCB for 1 phase & 3 MCB for 3 phase P.T.). Do notswitch ‘ON’ current circuit MCB’s.

5.6.2 Adjust the phase voltages by varying voltage variacs to100V.

5.6.3 Record primary and secondary voltages.


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METERING / PROTECTION C.T1. Objective TEST ING OF METERING / PROTECTION C.T. BANK


0-5 KV HV Test Set, Vernier caliper , scale, CTPT Test Set(0-30 KV HV test set for 11KV CT)

3.Responsibility Testing is to be done by Minimum T-8 grade officer.

4. Reference IS NO.: - 2705 / 1992 (part 1 to part 4)BEST Specifications & Latest approved drawing

5. Procedure 5.1 : Sampling :- All CTs received are to be tested.

TEST CONDUCTED1) H.V.Test on primary winding. (cl. 9.3 of part-1)2) H.V.Test on secondary winding. (cl. 9.4 of part-1)3) Accuracy test at different load points & at rated burden. (cl.

3.3.1 of part-2) for metering CTs.4) Accuracy test at 100%load at rated burden. (cl. 5.1 of part-3)

for protection CT.5) Physical inspection & dimensional analysis (for ‘proto-type’

C.Ts only) (As per BEST specification)6) Continuity test an potential terminals.7) Measurement of Knee point voltage ( cl. No. 6.1 of part-4)

5.2 : PHYSICAL INSPECTION

1) There shall be no damage to body, primary bus bar, secondaryterminals, potential terminal, mounting channel.

2) Polarity & terminals on each phase shall be marked.3) Name plate of the C.T. shall certain following information.

a) The manufactures name & country of origin.b) Year of manufacture.c) A serial number & a type designation.d) The rated primary & secondary currents.e) Rated frequency & rated voltage.f) Rated output & the corresponding accuracy class.g) Highest system voltage.h) Rated insulation level.i) Rated short time terminal current or short time factor with

rated time.j) Knee point voltage , rated burden.k) Secondary winding resistance.l) Reference of the standard.

5.3 : DIMENSIONAL ANALYSIS (for prototype C.T.s only)As per BEST approved drawings.Following dimensions are to be takenCentre to centre distance between secondary terminalsIS – 1L, 1L – 2S, 2S – 2L, 2L – 3S, 3S – 3L, 3L – N.

52

Length of secondary terminals, distance of secondary terminalsfrom body surface, length of potential terminals, length of primarybus bar (top position), length of primary bus bar (bottom position),width of primary bus bar, thickness of primary bus bar.

5.4 : H.V.TEST ON PRIMARY WINDING (cl. 9.3 of part-1)Equipment :- H.V.Test set (0-5kv)for LV CT and (0-30 KV) set for11 KV CT.i) Short all the secondary terminals & connect it to earth.ii) Short all potential terminals & primary bus bar & connect the

phase probe of H.V.Test set this shorted terminal.iii) Connect the earthing probe of H.V.Test set to the secondary

shorted terminal & earthed.iv) Slowly increase the H.V.Voltage at a rate 2 % per second to 3

kv for LV and 28 KV (for 11 KV ) & maintain this value ofvoltage for 1 minute.

v) There should not be any disruptive discharge or breakdown.

5.5 : H.V.TEST ON SECONDARY WINDING (cl. 9.4 of part-1)Equipment.:- H.V.Test set (0-5kv)i) Short all the primary bus bar & potential terminals & connect it

to earth.ii) Short all the secondary terminal together (of all 3 phase).iii) The test voltage of 3 kv (rms) shall be applied for one minute

between the terminals of the secondary winding ( connecttogether) & earth.

iv) Connect the phase probe of H.V.Test set to the secondarywinding (connect together) & earth probe to primary windingshorted & earthed.

v) Slowly increase the H.V.Voltage at a rate of 2% voltage persecond up to 3kv maintain this value of test voltage. For oneminute. There should be no disruptive discharge.

5.6 : ACCURACY TEST AT RATED BUDEN

This test is to be performed on ELTEL make CT TEST set .

Procedure for testing 5A Test CT using 5A StandardCT.

Make the back panel connections as shown in Fig 3-11. The 5ASTD CT Secondary terminals are to be connected to the STDterminals on the back panel. The 5A Test CT secondary terminalsare connected to the test terminals on the back panel. Connect thedesired burden across the test CT terminals. Switch on the AITTS-98 test set and other related equipments.

From the AITTS-98 main menu, press any key, this will display the

53

first menu. Now press ‘3’ which is the selection menu to enter allthe parameters as desired.

In the selection menu enter-‘1’ – here you can choose either % orabsolute value by again pressing ‘1’.

Enter‘5’- to choose ‘5A’ since your test input is a 5A CT.Enter‘2’- do you wish to view the ratio error either in % or in ppm?By pressing ‘3’, the cursor can be shifted to select either % or ppm.

Enter‘3’- do you wish to view the phase error either in min or inrad? Press ‘4’ to choose either parameter.

Enter‘4’ – do you wish to have the accuracy class printed as perANSI, IEC,IEC-S, IS-P, IS-PR, AS-M, AS-ME, BS or BS-S.Choose appropriate digit to select the same.

Enter‘7’- enter 5 using the keypad as you will be using a 5Astandard to test CT’s with sec 5A.

Now this completes the selection of the menu. Now by pressing‘ENTER’ all the above details will be retained in memory and thedisplay will return to the first menu.

To enter the customer specification, press ‘5’. This will display thecustomer settings screen.

Press ‘1’- the serial number of the test Ct can be entered. A totalof 9 digits can be entered. Use “” & “ ” arrow keys toincrease or decrease SI# in CT/VT menu only.

Press ‘2’- the burden value can be entered 10 digits. Then pressenter.

Press ‘3’- the ratio of the test Ct can be entered. Upto 6 digits forthe primary value and 5 digits for the secondary value can beentered.

Option ‘4’- the testing date will be displayed in DD/MM/YYYYformat.

Press’5’- either to activate or deactivate Auto print facility.

54

Press’6’- to select short or regular print formats.

After completing this menu, press ‘ENTER’ to retain above valuesin memory a long beep will occur. After pressing ‘ENTER’, thedisplay returns to the first menu. This now completes the panelentries for the AITTS-98.

Now from the first menu, press ‘2’ to go to the CurrentTransformer menu.

Increase the current to the test and STD CTs observe the frontpanel to check the current value. Raise the current to 120% ofrated value (either in value or in %). Note down the ration errorand phase error readings.

Bring down the current value to 100% of rated value and take thereadings of ratio and phase errors. Repeat the above procedure for5% of current value.For printing the results, press F3. This feeds the test results to theprinter.Further Details for using CT/PT Test set is in given in EQP-132file.

The ratio error & the phase angle error shall be within thelimits provided in table 1A of IS 2705 (Part 2)

Accuracy Percentage Current (ratio) Phase Displacement Is MinutesClass At Error At % Of Ratio Current At % Of Rated Current

% ofrated

current

5 20 100 120 5 20 100 120

0.1 0.4 0.2 0.1 0.1 15 8 5 50.2 0.75 0.35 0.2 0.2 30 15 10 100.5 1.5 0.75 0.5 0.5 90 45 30 301.0 3.0 1.5 1.0 1.0 180 90 60 60

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Table 1 C Limits of Error for Special application AccuracyClasses 0.2 S and 0.5 S

Accuracy Percentage Current (ratio) Phase Displacement Is MinutesClass At Error At % Of Ratio Current At % Of Rated Current

% ofrated

current

1 5 20 100 120 1 5 20 100 120

0.2S 0.75 0.35 0.2 0.2 0.2 30 15 10 10 100.5S 1.5 0.75 0.5 0.5 0.5 90 45 30 30 30

Table 1 of part -3 Limits of errors for protection CTsAccuracy

classCurrent error

at ratedprimary current

(percent )

Phase displacementat rated

primary current( Minutes)

Composite Errorat rated

Accuracy limitprimary current

5P + 1 + 60 510P + 3 - 1015P + 5 - 15

5.7 Measurement of Knee point voltage ( cl. No. 6.1 of part-4)

5.7.1 For protection CTs knee point voltage is specified on nameplate. Our specified value is 35 V for 11 KV sub-station CTs.

5.7.2 Connect a voltmeter across the secondary terminal S1 & S2.5.7.3 Connect single phase supply and an ammeter in series with

S1 & S2 through variac.5.7.4 Increase the voltage upto 35V and note down the currentA1.5.7.5 Increase the voltage to 38.5V and note down the current.

Current thus recorded shall not be more than 150% of A1.

In case knee point voltage is not marked connect the circuitas per para 5.7.2 & 5.7.3 and go in increasing the voltage. At aparticular point there will be a sharp rise in current. At thattime stop increasing voltage. Calculate knee point voltage asper its definition.

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ADAPTER FOR BANK TYPE METERING CTs

1. Objective Testing of Adapter for Bank type metering CTs


Same as required for testing metering CTs.

3.Responsibility Testing is to be done by minimum T-8 grade officer.

4. Reference IS NO.: - 2705 / 1992 (part 1 to part 4)BEST Specifications / Latest approved drawing

5. Procedure 5.1 : Sampling: 10 % of the lot quantity.

(Adapters are procure to use different type of meters withsame metering CT bank and vice versa. i.e. if potentialterminals and current terminals of meter are not matching withthose of CT, adapter is used as a coupler to make thecombination useful.)

5.2 : IR Test : When test with 500 v megger insulation betweenterminals as well as those between terminals and body shall bemore than 50 MΩ.

5.5 : HV Test: It is to be done in similar way that is defined formetering CT secondary winding (cl. 9.4)Equipment.:- H.V. Test set (0.5kv)

5.5.1 Short all the primary bus bar & potential terminals &connect it to earth.

5.3.2 Short all the secondary terminal together (of all 3 phase).5.3.3 The test voltage of 3 kv (rms) shall be applied for one

minute between the terminals of the secondary winding (connect together) & earth.

5.3.4 Connect the phase probe of H.V. Test set to the secondarywinding (connect together) & earth probe to primarywinding shorted & earthed.

5.3.5 Slowly increase the H.V. Voltage at a rate of 2% voltageper

second up to 3kv maintain this value of test voltage. For oneminute. There should be no disruptive discharge.

5.4 : Accuracy Test: This test is to be performed on ELTEL makeCT TEST set as per the procedure prescribed in Chapter for“METERING/PROTECTION C.T.”

58

The ratio error & the phase angle error shall be within thelimits provided in table 1A of IS 2705 (Part 2)

5.4.1 Initially test a metering CT ( given by DEEC as referenceCT ) for accuracy .

5.4.2 Now connect the adapter under test on same CT andconsider terminals of adapter as terminals of CT and repeatthe accuracy test. Ratio and phase angle error should bewithin specified limits.


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RING C.T. ( LV Metering)

1. Objective TEST ING OF L.V.METERING C.T. ( Ring Type)


0-5 KV HV Test Set, Al. Bus Bar strip , CTPT Test Set


4. Reference IS NO.: - 2705 / 1992 (part 1 to part 4)BEST Specifications / Latest approved drawing

5. Procedure 5.1 : Sampling :-100% Testing i.e. all CTs received are to be tested.

TEST CONDUCTED

8) H.V. Test on primary winding.9) H.V. Test on secondary winding.10) Accuracy test at different load points & at rated burden.


4) There shall be no damage to body, secondary terminals,mounting channel.

5) Polarity & terminals shall be marked.6) Name plate of the C.T. shall certain following information.

m) The manufactures name & country of origin.n) Year of manufacture.o) A serial number & a type designation.p) The rated primary & secondary currents.q) Rated frequency & rated voltage.r) Rated output & the corresponding accuracy class.s) Highest system voltage.t) Rated insulation level.u) Rated short time terminal current or short time factor with

rated time.v) Reference of the standard.

5.3 : H.V.TEST ON PRIMARY WINDING (cl. 9.3)Equipment :- H.V. Test set (0-5kv)

5.3.1 Take an aluminum bus bar of appropriate size and pass itthrough ring CT and consider this aluminum bus bar asprimary for testing purpose.

5.3.2 Short all the secondary terminals & connect it to earth.

60

5.3.3 Connect the phase probe of H.V. Test set with primary busbar Connect the earthing probe of H.V. Test set to thesecondary shorted terminal & earthed.

5.3.4 Slowly increase the H.V. Voltage at a rate 2 % per secondto 3 kv & maintain this value of voltage for 1 minute.

5.3.5 There should be disruptive discharge.

5.4 : H.V.TEST ON SECONDARY WINDING (cl. 9.4)Equipment.:- H.V. Test set (0-5kv)

5.4.1 Keep the aluminum strip through ring and connect it toearth.

5.4.2 Short all the secondary terminal together.5.4.3 Connect the phase probe of H.V. Test set to the secondary

winding (connect together) & earth probe to primarywinding (i.e. aluminum strip)/earthed.

5.4.4 Slowly increase the H.V. Voltage at a rate of 2% voltage persecond up to 3kv. Maintain this value of test voltage for oneminute. There should be no disruptive discharge.

5.5 : ACCURACY TEST AT RATE BUDEN

IMP: While testing ring CTs Flexible cores are to be used asprimary bus-bar.This test is to be performed on ELTEL make CT TEST set as perthe procedure prescribed in prescribed in Chapter for

“METERING/PROTECTION C.T.”

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SUMMATION CTs

1. Objective Testing of Summation CTs


0-5 KV HV Test Set, Al. Bus Bar strip , CTPT Test Set


4. Reference IS-6949/1973 and 2705/ 1992

5. Procedure 5.1 Sampling: All samples are to be tested.

TEST CONDUCTED1) H.V. Test on primary winding.2 ) H.V. Test on secondary winding.3) Accuracy test at different load points & at rated burden.

5.2 : IR Test : When tested with 500 v megger insulation betweenterminals as well as those between terminals and body shall bemore than 50 MΩ.

5.3: HV Test:5.3.1 Short all the primary terminals & connect it to earth.5.3.2 Short all the secondary terminal together.5.3.3 The test voltage of 3 kv (rms) shall be applied for one

minute between the terminals of the secondary winding(connect together) & earth.

5.3.4 Connect the phase probe of H.V. Test set to the secondarywinding (connect together) & earth probe to primarywinding shorted & earthed.

5.3.5 Slowly increase the H.V. Voltage up to 3kv maintain thisvalue of test voltage. For one minute. There should be no

disruptive discharge.

5.4 : Accuracy Test: This test is to be performed on ELTELmake CT TEST set as per the procedure prescribed inprescribed in Chapter for “METERING/PROTECTION C.T.”

1 Connect all primary winding in series.

IMP 2 Select ratio as 5/5 for primary/secondary.3 Inject only 5 amp. In primary for testing.4 Repeat the procedure for all three phases.

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RCC TILES (33kv)/ TROUGH for straight joint

1. Objective Testing of RCC TILES (33kv)/ Trough for straight joint


Weighing machine , oven, scale, vernier caliper,


4. Reference IS NO. 458 / 1988IS No. 3597 / 1985, BEST Specification , Latest approved drawing

5. Procedure 5.1: Sampling: Randomly selected One tile / Trough per lot( As per MTS )

TEST CONDUCT

1) Physical inspection2) Dimensional analysis3) Water absorption


i) There shall be no damage to tile, disc voltage (33000 volt)shall clearly read & also their letter size should be as perdrawing. “ BEST” letter shall also be clearly read & theyshould be of proper size as per drawing.

ii) Shape of the file should be as per drawing.

5.3 : DIMENSIONAL ANALYSIS

AS PER DRG.ES/PE/A-76Following dimension are to be checkedMeasure the total length ,total width ,total height

Then break the tile & separate the steel structure & measure thefollowing dimensions.Length of horizontal rod.Diameter of horizontal rod.No. of horizontal rods.Length of vertical rods.Diameter of vertical rods.No. of vertical rods.Also observe that , M.S. rods are tied with G.I. wire or not.

63

5.4 : WATER ABSORPTION TEST

1) cl. 9.2.2 (b) of IS – 458 / 1988 , Spec – 6.5% (max)2) procedure - IS – 3597 / 1985 (cl.6)

i) RCC tile shall be dried in a oven at a temperature of 105 to115 C until two successive weighing at interval of not lessthat 8 hours show an increment of less not greater than 0.1percent of the mass of the tile. The drying time shall notless than 36 hours. The dry mass of file shall be the massafter the final drying , determined at ambient temperature.

ii) After drying & weighing , the RCC file shall be immersedin clean water at room temperature for 24 hours.

iii) After 24 hours RCC tile shall then be removed from thewater & allowed to drain for not mere than 1 minute. Thesuperficial shall then be removed by absorbent cloth orpaper & the tile weighed immediately.

iv) All weighing shall be made to an accuracy of 0.1 percent ofthe mass of the test tile.

v) The increase in mass of the test tile over its dry mass shallbe taken as the absorption of the file & shall be expressedas a percentage of the dry mass.

Water Absorption = Final weight – Dry weight x 100Dry weight


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POWER CAPACITOR1. Objective Testing of Power Capacitor ( 28/ 56 KVAr)

2. Apparatus

/ material

0-5 KV HV Test Set, 500 V Megger, Soken Make Bridge,Multimeter , Stop Watch ,

3.Responsibility Testing is to be done by minimum T-8 grade Officer.

4. Reference IS No. 13585( P 1 ) - 1994

5. Procedure 5.1 Sampling:As per IS No. 13585( P 1 ) – 1994 table -5

Lot Size Sample Size Permissible Nos. ofdefectives

Upto 100 8 0101 to 300 13 0301 to 500 20 1501 to 1000 32 21001 and above 50 3

5.7 : IR Test: [Ref. cl. 16 ]

Apparatus - 500V megger:

Insulation is to be measured between terminals (allconnected together externally) & the container/ earthingterminal. It should be more than 50 MΩ.

5.3 : HV Test : [Ref. cl.18.1]With the help of 0-5 KV HV Test set 3 KV AC volt( ref.

table 3) is to be applied for 10 seconds , between terminals(all connected together externally) & the container/earthing terminal. No flashover or breakdown should occurduring this period.

5.4 : TEST FOR EFFICACY OF DISCHARGE DEVISE :[Ref. cl.19.2]This test is to be performed on individual units of all8 randomly selected capacitors ( keeping dischargeresistance in circuit). With the help of 0-5 KV HV Testset apply a DC voltage 1.4 times the rms rated voltageto the capacitor. Disconnect the source and measure

65

the voltage across capacitor terminals. The momentmeter shows value equal to 1.4 times the rms ratedvoltage, start the stop watch . Voltage should reachbelow 50 volts within 1 minute.

5.5 : Measurement of Capacitance & Tan Delta( Refer clause no. 15.1 & 15.2)This test is to be performed on Soken makemeasuring instrument .Connect the circuit as perdiagram shown in fig. While measuring Capacitance &Tan Delta on ‘RY’ of capacitor keep ‘YB’ short and viceversa. Switch on contactor then make instrument ON. With the help of variac, increase the voltage upto therated voltage. Note down the capacitance values in µFand tan delta value directly from indicators .Repeatthe three sequences.Calculation:

Q=2 Cry+Cyb+Crb ω xU2 x 10-9

3Where Q= Expressed in KVAr

C = Capacitance in µFω = 2πFU= voltage

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CAPACITOR FOR LANTERN

1. Objective Testing of Capacitor for Lantern


0-5 KV HV Test Set, 500 V Megger, Capacitance Meter


4. Reference IS 1569/1976 , BEST Specification

5. Procedure 5.1 Sampling: Table 6

Lot Size N1 N2 N1+N2 C1 C2

51 to 100 10 20 30 0 3

101 to 200 13 26 39 0 5

201 to 300 20 40 60 1 5

301 to 500 25 50 75 1 6

501 to 800 35 70 105 2 7

801 to 1300 50 100 150 3 10

1301 to 3200 75 150 225 5 12

5.2 : IR Test: [Ref. cl. 5.12.4.1 ]Insulation is be measured between terminals (all connectedtogether externally) & the container/ earthing terminal. Itshould be more than 10 MΩ, when meggered with 500 vinsulation tester.

5.3 : HV Test : [Ref. cl.5.7]With the help of 0-5 KV HV Test set 2 KV AC volt is to be

applied for 1 minute , between terminals (all connectedtogether externally) & the container/ earthing terminal. Noflashover or breakdown should occur during this period.

( If container is of non metallic material then wrap it withmetal foil and take this metal foil as body reference for IR andHV tests.)

68

5.6 Measurement of Capacitance: [Ref. cl.5.8]Switch ON shivanand make capacitance measuring instrument.Connect both leads of instrument to the respective leads ofcapacitor under test. By selecting ranges, values of capacitor canbe read directly in µF.

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UNARMOURED CABLES (COIL FORM)

1.Objective Testing of Un- armoured Cables in coil form (Copper & Aluminum)(0.5 sq.mm to 2.5 sq. mm., 6 sq.mm,10 sq.mm,16 sq.mm & 25 sq.mm etc. )


Micro- ohm Meter( Single Channel Prestige Make). Vernier Caliper,Cleaning Solvent, Cable cutting tools etc., Digital Temperature Indicator,HV Test Set 0- 5 KV, Measuring tape.

3.Responsibility Testing is to be done by Minimum T-5 grade staff.4.Reference IS -694/ 2010 & IS -8130/2013

5.Procedure 5.1 : Sampling ( Annexure- A Table -11)Cl.no.14. (Clauses A- 2.2 and A-3)Bring nos. of randomly selected coils from stores as per the table givenbelow:

Size of lot no. of samples Permissible nos. of DefectiveUp to 50 3 051 to 100 5 0101 to 300 8 0301 to above 13 1

5.2 : HIGH VOLTAGE TEST (At room temp.)Cl. 10.2 of IS :- 694 / 2010

Single core cables shall be immersed in water at ambient temperature1 hour before the testing. The conductors at both the ends should betied together. Phase should be applied to the conductor & earthterminal is to be immersed in water. The cables & cords shallwithstand without breakdown an ac voltage of 3 kv (rms) applied fora period of 5 minutes.

5.3 : RESISTANCE OF CONDUCTOR

Table 2 of IS – 8130/2013 IS – 10810 (Part-5) / 1984Table 3 of IS – 8130/2013Table 4 of IS – 8130/2013

Apparatus :- 1) Prestige Make Micro Ohm Meter2) Suitable connecting leads3) Thermometer least count 1 C4) Measuring Tape

TEST SPECIMEN

a) All solid .circular conductor Drum length or 1 mb) All stranded or sector shaped Drum length or 5 m

solid conductors up to & including25 mm2 size

c) All stranded or sector shaped solidConductors greater than 25 mm2 size Drum length or 10 m

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It shall be ensured that the test specimen has attained the ambienttemperature. Switch ‘ON’ Micro Ohm- meter and confirm the ‘zerosetting’. The test specimen is connected to the Micro Ohm Meter withwooden stand in such a way that both Voltage probes are on inner side andboth Current probes are on outer side. The resistance of the test specimen ismeasured & the ambient temperature is to be recorded. The measuredresistance is converted to the standard temperature & standard length.

For temperature correction factor,

Ref. Table 1 of IS 10810 (P5) / 1984

Temp. corr. Factor = 250250 + t

During the resistance measurement the magnitude of the current shallbe such that there is no heating up of the test specimen.

After completion of test on all samples, the length of one sample is to beverified which show highest resistance in comparison with other samples soas to confirm the results. For verifying length of the coil measure theresistance of all the sample coils for entire length.

5.4 : OXIDATION TESTAll the samples should be examined physically for oxidation/ tarnishingof conductor on both end. In case any sample found oxidized/ tarnishedthen a 2 meter piece is cut & then rechecked for the same.

5.5 : DIMENSIONS

All the dimensions are to be checked as per test report format.( ref Table-4 & Table-5, Table-6, Table-7)Mainly : outer sheath, inner sheath, nos. of strand, size of strand etc.

6 . Test report Format to be selected as per the size of cable. In case of non std. size blankformat is to be used

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LV ARMOURED CABLES

1. Objective Testing of Armoured Cable of various sizes( 25/2c, 25/4c,70/4c/120/4c and 300/4c etc.)


Micro- ohm Meter( Single Channel Prestige Make). Vernier Caliper,Cleaning Solvent & HV Test Set 0- 5 KV, Cable cutting tools etc.,measuring tape, Thermo hygrometer.


4. Reference Best spec. No. :- 0130100/7 or latest specification of P.O.IS 1554 (P1) / 1988 , Table 2 of IS – 8130/2013.

5. Procedure 5. 1 : Sampling: Appendix A of IS 1554 ( Cl. 15.2.1)

Drum number marking is to be done on cables of all drums bypermanent marker. 1.1 mtr. for nos. of sample listed below, and 0.6mtr. On all other drums.

Size of Lot Nos. ofSamples

Permissible nos. of defective

Upto 50 2 051 to 100 5 0101 to 300 13 0301 to 500 20 1

5.2: Sampling for HV Test : Sampling for HV test on LV Armouredcables of various sizes is to be carried out as per MTS/MTL-14A/-/2014-15dated 26.02.2015.

Total no. of drumsreceived in a lot.

Nos. of Samples to be selected for H.V.Test (of length 3 mtrs) including 1.1 mtrsample piece of each IM or lot.

Upto 25 126 to 50 251 to 75 375 to 100 4

5.3: HV Test:-IS 1554 Cl.16.2.

Appratus :- H.V. test set of capacity – 5KV, 1A, 2A.Test specimen- cable piece length required min.- 3 mtr or entire drum.Testing Procedure:-

5.3.1 The high voltage source is connected to the conductor of the coreunder test. The cores not under test, screen and armour are connected to the

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earth terminal, depending on the mode of connections as given in Figure.

5.3.2 The voltage is to be raised sufficient slowly to permit accuratereading of the measuring instruments, but not so slowly as to causeunnecessary prolongation of the stress near the test voltage.

5.3.3 These requirements are in general met if the rate of rise above 75percent of the test voltage is about 2 percent per second of this voltage.However, different rate of rise may be used, but it should not exceed 2 000V/s.

5.3.4 The test voltage is raised to the specified value (3 KV) as describedin 5.3.2 and is maintained for the specified time. (5 mins). After thespecified time, the voltage is rapidly decreased but the voltage is notinterrupted suddenly to avoid the possibility of switching transients whichmay affect the subsequent test results.

5.4 : CONDUCTOR RESISTANCE TESTTable 2 of IS – 8130/2013IS – 10810 (Part-5) / 1984

Apparatus :- 1) Prestige Make Micro Ohm Meter2) Suitable connecting leads

3) Thermometer least count 1 C

TEST SPECIMENd) All solid ............... conductor Drum length or 1 me) All stranded or sector shaped Drum length or 5 m

solid conductors up to & including25 mm2 size

f) All stranded or sector shaped solidConductors greater than 25 mm2 size Drum length or 10 m

No. of specimens – All drums from which 1.1 samples are cut are selectedfor this test.It shall be ensured that the test specimen has attained the ambienttemperature. The test specimen is connected to the resistance measuringbridge in such a way as to minimize contact resistance. The resistance ofthe test specimen is measured for all cores & the ambient temperature isrecorded. The measured resistance is converted to the standard temperature& standard length.( to be reported in Ω/ Km at 20oC)For temperature correction factor,

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Ref. Table 1 of IS 10810 (P5) / 1984Temp. corr. Factor = 250

250 + t

5.5 : ARMOUR RESISTANCEIS – 1554 (P1) / 1988 – Table 6Apparatus :- Micro-Ohm Meter, Thermometer, measuring tape, cleaningsolvent, vernier caliper, cable cutting tools etc.No. of specimen :- Both the drums from which 1.1 m samples is cut.

TEST SPECIMEN :- Entire Cable drumThe drum length of cable shall constitute the test specimen. The length ofthe test specimen should be the length which lies between the potentialterminals no special conditioning is necessary except that it is to be ensuredthat the test specimen has attained that ambient temperature.

TEST PROCEDURE1) Short all the armour strips with the help of copper wire on both end.

2) Connect probes of Micro ohm meter on either end of drum. Adequatecare is to be taken in this connection to minimize contact resistance.

3) The resistance thus measured & the ambient temperature is recorded.4) The armour resistance is then converted at 20 C taking into account the

temperature correction factor and the length of cable.

5.6 : OXIDATION TEST (conductor & armour)( visual examination )It is to be checked on all the samples. In case the first sample is foundoxidized, then a 2 meter piece is cut from the same drum & rechecked.

5.7 : DIMENSIONSAll the dimensions are to be checked as per table 2 , table 4, table 6 , &table 7 of IS 1554 and IS 3975-1988 for tolerance for armour strips.,And clause no. 5.7.2 of BEST specification.

6. Test report Format to be selected as per the size of cable. In case of non std. size blank formatis to be used

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11 KV CABLES

1. Objective Testing of 11 KV Armoured Cable ( 50 sq. mm.)


Micro- ohm Meter( Single Channel Prestige Make). Vernier Caliper,Cleaning Solvent & HV Test Set 0- 30 KV, Cable cutting tools etc.


4. Reference Best spec. No. :- 0130100IS 1554 (P1) / 1988 , Table 2 of IS – 8130, IS 7098 / 1988

5. Procedure 5. 1 : Sampling: Appendix A of IS 1554 ( Cl. 15.2.1)

Drum number marking is to be done on cables of all drums by permanentmarker. 1.1 mtr. for nos. of sample listed below, and 0.6 mtr. On all otherdrums.



Upto 50 2 051 to 100 5 0101 to 300 13 0301 to 500 20 1

5.2 : CONDUCTOR RESISTANCE TESTTable 2 of IS – 8130IS – 10810 (Part-5) / 1984

Apparatus :- 1) Prestige Make Micro Ohm Meter2) Suitable connecting leads

3) Thermometer least count 1 C

TEST SPECIMENAll stranded or sector shaped solid

Conductors greater than 25 mm2 size Drum length or 10 m

No. of specimens – All drums from which 1.1 samples are cut are selectedfor this test.It shall be ensured that the test specimen has attained the ambienttemperature. The test specimen is connected to the resistance measuringbridge in such a way as to minimize contact resistance. The resistance ofthe test specimen is measured for all cores & the ambient temperature isrecorded. The measured resistance is converted to the standard temperature

75

& standard length.( to be reported in Ω/ Km at 20oC)

For temperature correction factor,Ref. Table 1 of IS 10810 (P5) / 1984

Temp. corr. Factor = 250250 + t

5.2 : ARMOUR RESISTANCEIS – 1554 (P1) / 1988 – Table 6Apparatus :- Micro-Ohm MeterNo. of specimen :- Both the drums from which 1.1 m samples is cut.

TEST SPECIMENThe drum length of cable shall constitute the test specimen. The length ofthe test specimen should be the length which lies between the potentialterminals no special conditioning is necessary except that it is to be ensuredthat the test specimen has attained that ambient temperature.

TEST PROCEDURE1) Short all the armour strips with the help of copper wire on both end.2) Connect probes of Micro ohm meter on either end of drum.

Adequate care is to be taken in this connection to minimize contactresistance.

3) The resistance thus measured & the ambient temperature isrecorded.

4) The armour resistance is then converted at 20 C taking into accountthe temperature correction factor and the length of cable.

53. : OXIDATION TEST (conductor & armour)( visual examination )It is to be checked on all the samples. In case the first sample is foundoxidized, then a 2 meter piece is cut from the same drum & rechecked.

5.4 : DIMENSIONSAll the dimensions are to be checked as per table 2 , table 3, table 5 , &cl. No. 11.3 of IS 7098(II) and IS 3975-1979 for tolerance for armourstrips., And BEST specification.

6. Test report Format to be selected as per the size of cable. In case of non std. size blank formatis to be used

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400 sq. mm Copper XLPE Cable

1. Objective Testing of Cable of 400 sq. mm Copper XLPE


Micro- ohm Meter( Single Channel Prestige Make). Vernier Caliper,Cleaning Solvent & HV Test Set 0- 5 KV, Cable ctting tools etc.

3.Responsibility Testing is to be done by Minimum T-5 grade staff.4. Reference IS 7098 (P1) / 1988

5. Procedure 5. 1 : Sampling Appendix A of IS 7098 (P1) / 1988 ( cl. No 15.2.1 )Drum number marking is to be done on cables of all drums bypermanent marker. 0.6 mtr. on each drums.



Upto 50 2 051 to 100 5 0101 to 300 13 0301 to 500 20 1

5.2 : CONDUCTOR RESISTANCE TESTTable 2 of IS – 8130IS – 10810 (P-5) / 1984

Apparatus :- 1) Micro-Ohm Meter2) Suitable connecting leads3) Thermometer least count 1 C

TEST SPECIMENAll solid ............... conductor Drum length or 1 mAll stranded or sector shaped Drum length or 5 m

solid conductors up to & including25 mm 2 size

All stranded or sector shaped solidConductors greater than 25 mm2 size Drum length or 10 m

No. of specimens – Any 2 drums from lot.It shall be ensured that the test specimen has attained the ambienttemperature. The test specimen is connected to the resistance measuringbridge in such a way as to minimize contact resistance. The resistance ofthe test specimen is measured & the ambient temperature is recorded. Themeasured resistance is converted to the standard temperature & standardlength.

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For temperature correction factor,Ref. Table 1 of IS 10810 (P5) / 1984= 250

250 + t

During the resistance measurement the magnitude of the current shallbe such that there is no heating up of the test specimen.

5.4 : OXIDATION( TARNISHING) TEST (Visual inspection ofconductor)

It is to be checked on all the samples. Incase first sample is foundtarnished, then a 2 meter piece is cut & checked for tarnishing.

5.5 : DIMENSIONS All the dimensions are to be checked as per table 3table 8 and Clause no. 2.2 of BEST specification.

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LEAD PIPE

1. Objective TESTING OF LEAD PIPE


Weighing machine , plastic putty , scale , vernier caliper, water ,liquid measuring jar


4. Reference IS NO. :- 404 (P I) / 1977Specification :-BEST Specification

5. Procedure 5.1 : SAMPLING: One meter piece from randomly selectedpipe per lot.

5.2 : : DIMENSION ANALYSIS

i) Length of pipe in meters:- With the help of measuring tapemeasure the length of any three pipe in meters at yard itself.Specified length is 2 meters.

5.3 : WEIGHT : Tender spec.

i) Note down the weight of the pipe & express it in kg /meter.

SIZE SPECIFIED VALUESID 75 7.5 kg / meter (approx.)

ID 100 9.88 kg / meter (approx.)ID 125 12.35 kg / meter (approx.)ID 150 16.36 g / meter (approx.)

5.4 : THICKNESS OF PIPE Tender spec. & 6.2 of IS404 (P I)

i) First clean the burr at the edge of the pipe with the help ofpolish paper.

ii) Measure the thickness by vernier at 5 different places. Itshould be 2.7 + 7.5 % mm at any point.

5.5: ID (Internal Diameter) :- Tender spec. 6.2 of IS404 (P I)

5.5.1 Cut a piece of approximately 100 cm in height.5.5.2 Fix the lead pipe vertically with the help of plastic putty.

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5.5.3 Take care that when the plastic putty dries there will be noleakage of water.

5.5.4 After the plastic putty dries up fill the lead pipe with waterwith the help of measuring jar.

5.5.5 Note down the quantity of water in liters (volume) requiredto fill the pipe completely.

5.5.6 Measure the height of the pipe at top water level. &Calculate the internal diameter as follows.

I.D = 2 / V x 10π h

V = Volume is millilitersH = Height is in cm

Tolerance for I.D is + 0% & - 5%


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Aluminum Solder and Plumbing Metal

1. Objective Testing of Aluminum Solder and Plumbing Metal


Weighing balance, scale


4. Reference IS – 5479 /1985 ( Solder stick Aluminum )IS- 193 /1982 ( Plumbing metal )

5. Procedure 5.1 Sampling: One stick per lot

5.3 Procedure :5.4 One sample from each lot is to be selected for testing

purpose.5.5 It is to be examined for its shape . It should be triangular

in shape ( 12mm x 12mm x 12mm ) + 2mm.5.6 Length of the stick shall be such that each stick shall

weigh 300 gms.( + 5 % )5.7 Each stick shall be legibly marked by embossing to

indicate manufacturers trademark and BEST monogram( i.e. B.E.S.T. )

5.8 Aluminum stick are marked yellow colour and PlumbingMetals are marked with green colour on tips of each stick.

5.9 Plumbing metal and Aluminum solder sticks are requiredto be checked for their chemical analysis. Metal analysis isnot feasible in our laboratory. Hence we get it done fromoutside laboratory. Presently we sent a piece of about20cm to outside laboratory.

It is being done at :

METAL ANALYSIS & SERVICES PVT. LTD.219, Busa Udyog Bhavan,Tokersy Jivraj Road,Sewree West , Mumbai- 400 015.

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INNER SLEEVE COMPOUND

1. Objective Testing of Inner Sleeve Compound


As prescribed in the procedure

3.Responsibility Testing is to be done by Minimum T-8 grade officer.4. Reference Test IS / Specification Referred

SOFTENINGPOINT

1. Specified Value as per Table 1 of IS702: 1988

2. Fig. 1 of IS 1205: 19583. Apparatus as per Clause 3 of IS

1205: 19784. Procedure as per Clause 4 of IS

1205: 1978PENETRATION 1. Specified Value as per Table 1 of IS

702: 1988 ( 15 + 4 )2. Apparatus as per Clause 3 of IS


1203: 1978

ELECTRICSTRENGTH (proof)

WEIGHT OF TIN :

1. Specified Value as per Table 2 ofIS 7084: 1973

2. Procedure : Appendix B of IS 7084:1973

3. Fig 6 of IS 7084:1973

Tender Specification ( 7 Kgs )

5. Procedure5.1 Sampling : Nos. of tin are to be brought as per table given below :

Size of lot No(s). of sample(s).Upto 1 12 to 15 2

16 to 50 351 to 150 5

151 to 500 8501 and above 13

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5.2 SOFTENING POINT TEST ( 90 0C + 3 0C )( on composite sample)

5.2.1 Apparatus:1. Steel balls (9.5 mm diameter & weighing 3.50 + 0.05 gms.) – 2 Nos.2. Brass Ring (shall be tapered) - 2 Nos.

Depth : 6.4 + 01 mmInside diameter at bottom: 15.9 + 0.1 mm

Inside diameter at top : 17.5 + 0.1 mmOutside diameter : 20.6 + 0.1 mm

3. Ball guide4. Support5. Thermometer (30 to 200oC)6. Beaker: 85 mm (diameter) & 120 mm deep7. Glycerin8. Stirrer9. Gas burner10. Stop watch

5.2.2 PROCEDURE :1. Heat the compound sample between 75oC to 100oC above its softening

point.Stirrer until it is completely fluid & free from air bubbles & water.

3. Fill the brass ring with above fluid compound above the level of thering.

4. After cooling for 30 minutes in air, level the compound in the ring byremoving the excess compound with a warmed sharp knife.

4. Assemble the apparatus with rings, thermometer, ball guides & ball inPosition & fill the beaker to a height of 50 mm above the uppersurface of the ring with glycerin.

5. Maintain the beaker with the above assembly at 5oC for 15 minutes.(Keep it in freezer) after which place a ball by means of forceps ineach ball guide.

6. Apply the heat to beaker & stir the liquid, so that the temperature risesat uniform rate of 5.0o + 0.5oC per minute. Maintain the above rate oftemperature strictly after the temperature reaches 35oC, and continuethis until the compound softens & allows the balls to pass through thering.

7. Record for each ring & ball, the temperature shown by the thermometer

83

at the instant the sample surrounding the ball touches the bottom plateof the support.

5.3 PENETRATION TEST5.3.1 Apparatus:1. A metal container2. Needle3. Water bath4. Penetrometer5. Time device6. Weight 50 gms

5.3.2 PROCEDURE

1. Soften the compound to a pouring consistency at temperature not morethan 90oC above the respective approximate softening point (90 + 3oC) &stir it thoroughly until it is homogeneous & free from air bubbles &water.

2. Pour the melt into the container to a depth at least 10mm in excess ofthe expected penetration (19 + 10 = 29mm)

3. Protect the sample from dust & allow it to cool in an atmosphere at atemperature between 15 to 30oC for 1½ to 2 hours for 45 mm deepcontainer & for 1 to 1 ½ hour when the container of 35 mm deep is used.

4. Place it in the water bath at 25 + 0.1oC & allow it to remain for 1 ½ to 2hours & 1 to 1 ½ hour for 45 mm & 35 mm deep container

5. Place the compound container (sample under test) upon the stand of thepenetration apparatus. Adjust the needle (previously washed clean withbenzene, carefully dried, and loaded with the specified weight) to makecontact with the surface of the sample.

6. Unless otherwise specified, load the needle holder with the weightrequired to make a total moving weight (i.e. the sum of the weights ofneedle, carrier & superimposed weights) of 100 + 0.25 grams.

7. Adjust the pointer to 0. Release the needle for 5 seconds & measure thedistance penetrated by pressing the pointer arm. Express the depth of thepenetration of the needle in tenths of millimeter. (i.e. no. of division ofthe penetro-meter). Make at least 3 determination at 3 different point 10mm apart. After each test return the sample and transfer dish to the waterbath , and wash the needle clean with benzene and dry.

84

5.4 ELECTRIC STRENGTH (proof)5.4.1 Apparatus:HV Test set (0 – 30KV), Steel cup container , square plate of insulatingmaterial, Steel or brass stud with spherical shape,1.25 mm gauge5.4.2 Procedure1. Adjust the gap of 1.25mm between spherical brass electrode of

Diameter 150 mm & the bottom of the cup with the help of gauge(thickness: 1.25mm).This may be checked by marking the surface of spherical electrode withchalk & the length of the electrode gradually adjusted till the sphericalelectrode touches the gauge.3. The compound in a solid form is put in a steel container & heated to

as a temperature of about 90oC, (which is the pouring point ofcompound).Compound level should be minimum 25 mm abovespherical electrode.

4. The vessel & compound are maintained at 90oC (pouring point) for atleast 1 hour to ensure that all air bubbles have dispersed.

4. The compound is then cooled slowly to the test temperature of 60 + 1oC.This temperature is maintained for at least three hours before the test ismade to ensure that the temperature at the electrodes is the correct testtemperature.

5. To maintain the test assembly temperature at 60 + 1oC, the testassembly is put in an oven, which is brought to a temperature of 60 + 1oCand maintained for 3 hours.

6. After 3 hours of conditioning, take out the test assembly & bring it tothe HV test cabinet. Phase is given to the spherical electrode & earth tosteel the steel cup.

7. The voltage from the HV Test set (0 – 30KV) is gradually raised fromzero to test value of 15KV (given in Table 2) in approximately 10seconds, & is maintained at that value for one minute. There shall be noflashover.

5.5 WEIGHT OF TIN :The weight of the tin should be as per the Tender Specification whenweighed on weighing balance machine of 30kg.


85

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OUTER SLEEVE COMPOUND

1. Objective TESTING OF OUTER SLEEVE COMPOUND (GRADE 75 / 15)


As prescribed in the procedure


4. Reference

5 Procedure

Sampling : ( table2 Appendix A of 702 /1988 )

Size of lot No(s). of sample(s).

upto 50 351 to 150 5

151 to 500 7501 and above 10

Test IS / Specification Referred

SOFTENING POINT TEST 1. Specified Value as per Table 1 of IS702: 1988

2. Fig. 1 of IS 1205: 19783. Apparatus as per Clause 3 of IS


1205: 1978PENETRATION TEST 1. Specified Value as per Table 1 of

IS 702: 19882. Apparatus as per Clause 3 of IS


1203: 1978WEIGHT OF TIN (in Kgs) Tender Specification

5.1: SOFTENING POINT TEST ( Specified value 65 0C to 80 0C)( on composite sample)

86

5.1.1: Apparatus:1. Steel balls (9.5 mm diameter & weighing 3.50 + 0.05 gms) – 2 Nos.2. Brass Ring ( shall be tapered) - 2 Nos.

Depth : 6.4 + 01 mmInside diameter at bottom: 15.9 + 0.1 mmInside diameter at top : 17.5 + 0.1 mmOutside diameter : 20.6 + 0.1 mm

3. Ball guide4. Support5. Thermometer (30 to 200oC)6. Beaker: 85 mm (diameter) & 120 mm deep7. Glycerin8. Stirrer9. Gas burner10. Time Device

5.1.2 : Procedure:1. Heat the compound sample to a temperature between 75oC & 100oC

above its softening point. Stir until it is completely fluid and freefrom air bubbles and water and

2. Fill the brass ring with above fluid compound above the level of thering.

3 After cooling for 30 minutes in air, level the compound in the ring byremoving the excess with a warmed sharp knife.

4. Assemble the apparatus with rings, thermometer & ball guides inposition & fill the beaker to a height of 50mm above the uppersurface of the rings with freshly boiled distilled water.

5. Maintain the beaker with the above assembly at a temperature of 5oCfor 15 minutes (keep it in freezer ).

6. After above conditioning, take out the test assembly and apply the heatto the beaker & stir the liquid, so that the temperature rises at theuniform rate 50C + 0.5oC per minute. Maintain the above rate oftemperature rise strictly uniform and continue this until thecompound softens & allows the balls to pass through the ring. Foreach ring & ball, record the temperature shown on the thermometer atthe instant the compound surrounding the ball touches the bottomplate of the support.

5.2: PENETRATION ( specified value is 10 to 20 )

5.2.1 : Apparatus: A metal container, Needle, Water bathPentrometer , Time deviceWeight 50 gms

87

5.2.2 : Procedure:

1. Soften the compound to a pouring consistency at a temperature notmore than 90oC above the respective approximate softening point(65 to 80oC) & stir it thoroughly until it is homogeneous & freefrom air bubbles & water.

2. Pour the melt into the container to a depth at least 10 mm in excess ofthe expected penetration (i.e. 19 + 10 = 29 mm)

3. Protect the sample from dust & allow it to cool in an atmosphere at atemperature between 15 to 30oC for 1 ½ to 2 hours with a 45 mm

deep container and 1 to 1½ hours when the container of 35mm depthis used.

4 Place it in the water bath at 25 + 0.1oC & allow it to remain for 1½ to 2 hour & 1 to 1 ½ hour for 45mm & 35 mm deep container,respectively.

5. Place the compound container (sample under test) upon the stand ofthe penetration apparatus. Adjust the needle (previously washed cleanwith benzene, carefully dried & loaded with the specified weight) tomake contact with the surface of the sample.

6. Unless otherwise specified, load the needle holder with the weightrequired to make a total moving weight (i.e. the sum of the weight ofneedle, carrier & superimposed weights) of 100 + 0.25 gms.

7. Adjust the pointer to O. Release the needle for 5 seconds & measurethe distance penetrated by pressing the pointer arm.

8. Express the depth of the penetration of the needle in tenths ofmillimeter (i.e.no. of divisions of the penetrometer)

5.3: WEIGHT OF TIN : ( 18 KG each )The weight of the tin should be as per the Tender Specification

when weighed on weighing balance machine of 30kg.


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EPOXY STRAIGHT JOINTS AND TERMINATION KITS

1. Objective Testing of Epoxy Straight joints and Termination Kits


0-5 KV HV Test Set, 0-30 KV HV Test Set, Electronic weighingBalance, Glass Thermometer, Stop Watch, Conical flask, Mouldsfor preparing specimens


4. Reference IS – 10333/1982 ( For materials ) IS-10877/1984IS-2584 / 1963 For testing procedurelatest BEST specification

5. Procedure 5.1 : Sampling:Any one randomly selected kit from the lot. Take one set ofresin and hardener from randomly selected kit for testingpurpose. And substitute them by extra resin and hardener setsupplied with the lot.

5.2 : Dimensional analysis & Physical check :5.2.1 Dimensions of Moulds are to be checked as per relevant

BEST / IS drawing.5.2.2 Physical examining of accessories as per check list.

As per clause no. 6,7, 8 & 9.5.3 Preparing test specimen: ( 11.2 of IS 10333 / 1982)5.3.1 Two nos. of square shape mould of metal are prepared for

making specimen for HV test.( 150mm x 150 mm )5.3.2 Two nos. of plastic caps of dia around 50mm and depth

around 10mm are used to prepare specimen for waterabsorption test.All the specimen shall be conditioned at least for 16Hrs. at27 + 20 C. and relative humidity of 65+/- 2%.

5.4 Rise in Temperature and Hardening time: ( 11.4 of IS10333 / 1982 & 4.3 of BEST specification )

5.4.1 Add the hardener in resin compound as prescribed by themanufacturer and mix it by stirring it for five minutes.

5.4.2 Fill the flask with 200 ml of mixture.( Remaining quantityshall be used for preparing specimen for HV test and Waterabsorption test.) Fix thermocouple in the middle of the flask.Place the flask in a liquid bath which is at 27+ 0.5 0C . The

89

surface of the reaction resin molding material shall below10mm of the liquid level. Record the rise in temperature andthe time to reach maximum temperature.

5.4.3 Raise the glass rod slightly at the interval of 15 seconds assoon as the flask can also be lifted with the rod hardness isattained. Time shall be recorded as hardening time.

5.5 HV test: ( Table 2 of IS 10333 / 1982 )This test shall be carried out on specimen prepared by usingmould detailed in 5.3.1.(HV 0-30 KV Test Set)The test shall be carried out by rapidly rising method asdescribed in clause no. 7 of IS-2584/1963. The voltage shallbe raised from zero at a uniform rate such that the breakdown occurs on an average in between 10 or 20 seconds.The electrical strength shall be the highest voltage which itwithstood for 20 seconds without breakdown.( Measure thethickness of specimen at break point for calculating thedielectric strength. )( specified value for LV , 8KV / mm & 15 KV/mm for HV)

5.7 Water absorption Test: ( Table 2 of IS 10333 / 1982 )This test shall be carried out on specimen prepared byusing mould detailed in 5.3.2.Take the weigh of the specimen before putting the specimenin distilled water. Let it be immersed in water for a period of24 +/- 1 hour at a temperature 27+ 2 0C. On removal fromwater , quickly wipe the surface with clean cloth or blottingpaper and re-weigh the specimen within 2 minutes of itsremoval from water. Take average of five readings.The maximum water absorption shall be as per Table 2 ofIS-10333/1982 . ( specified value is 50mgs )

5.8 Volume measurement: ( As per tender specification )Take the water in a measuring jar .Fill the upper mould withthis water. Measure the volume with reference to the waterrequire to fill mould . Repeat the test with lower mould. Totalvolume is to be recorded.


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AIR BREAK CONTACTOR

1. Objective Testing of Air Break Contactor

2. Apparatus

/ material

0-5 KV HV Test Set, Single Phase Loading Transformer, multi-meter, tong tester , thermometer , Variac. Ohm meter


4. Reference IS 13947 ( Part I & IV), BEST specification

5. Procedure 5.1 Sampling: 2 contactors per lot.( as per practice in MTS dept.)

Test to be conducted :1. HV Test on main contacts2. HV Test on auxiliary contacts3. Temperature rise test measurement on external main contact4. Temperature rise test on coil5. Closing voltage6. Drop out voltage

5.2 : HV Test on main contacts:( As per table X and cl. No. 8.3.3.4 of IS-13947 P-4 sec.1)

Shorten all current carrying terminals of main contact.Connect HV probe of 0-5 KV HV Test set to this combinedterminal .Connect earthing probe to the metallic frame wrapped aroundcontactor.Apply 2.5 KV for 1 minute by setting timer.No breakdown or flashover should be observed during thisperiod.

5.3 : HV Test on auxiliary contacts:( As per cl. No. 8.3.3.4 of IS-13947 P-4 sec.1)Shorten all current carrying terminals of auxiliary contact.Connect HV probe of 0-5 KV HV Test set to this combinedterminal .

91

Connect earthing probe to the metallic frame wrapped aroundcontactor along with main contacts.

Apply 1.5 KV for 1 minute by setting timer.No breakdown or flashover should be observed during thisperiod.

5.4 Temperature rise test on main contact:( As per table II to of part 1 and cl. No. 8.3.3.4 of IS-13947

P-4 sec.1)This test is to be performed on single phase loadingtransformer.With the help of variac connect the coil circuit of contactor.Connect the main contact in series and then connect them

Across 2 terminals of loading transformer.Switch on the contactor by applying 240 volts through variac.After switching ON loading transformer , Inject the ratedcurrent though contactor using coarse and fine tuning.Note down the time and let it remain ‘ON’ for four hours.After four hours switch OFF the loading transformer andsupply to the coil, and note down the temperature at differentplaces on main contact .Take the maximum one on record.

5.5 Temperature rise on coil :( As per table II of part 1 and cl. No. 8.3.3.3.6 of IS-13947

P-4 sec.1)Before starting above test (i.e. Temperature rise test onmain contact), measure the cold resistance of coil with thehelp of ohm-meter.After completion of (temperature rise test on contactor) whenSupply to the coil is disconnected , note down the hot

resistance of the coil with the help of ohm-meter.With the given formula calculate the temperature rise on coil.

Max. Temp. = R2 [234.5 + Rt.] – 234.5 °CR1

Where, R1= Resistance of winding before heating.


Rt = Room Temp. in oC.

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5.6 Closing voltage :( As per cl. No. 7.2.1.2 of IS-13947 P-4 sec.1)

Electromagnetic contactors shall close satisfactorily at anyvalue between 85% and 110% of their rated voltage.Confirm the same by using variac and multi-meter.

5.10 Drop out voltage :( As per cl. No. 7.2.1.2 of IS-13947 P-4 sec.1)The limits between which contactors shall drop out and openfully are 75% to 20% of their rated voltage. Confirm thesame by keeping contactor “ON” and slowly reducing thevoltage of the coil. ( using variac and multi-meter)


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M. C. B.

1. Objective TESTING PROCEDURE FOR M . C. B.


Megger(0-500V D.C), 0-5 KV HV Test Set, Loading transformer, DigitalClamp meter, Thermometer, Timer, Digital Temperature Indicator.


4. Reference IS 60898(P-I) /2002

5. Procedure 5.1 Sampling : Sampling is to be done as per IS 60898(P-I) /2002Annexure C, Clause no C.2 Table C.2. The separate 3 no of samples for testsequence ‘B’ ( Dielectric properties & Temp. rise test) & test sequence ‘ D’( Tripping characteristics) as per table C.1 of Annexure C are to be taken.

TEST CONDUCTED:

1) Dielectric properties & isolating capacity(Cl.9.7)2) Temperature rise & Measurement of Power loss (Cl.9.8)3) Test of Time current characteristics at 1.13 times of rated

current(Cl.9.10.1.1)4) Test of Time current characteristics at 1.45 t````imes rated current

(Cl.9.10.1.1)5) Instantaneous tripping at 2.55 times of rated current(Cl.9.10.1.2)

5.2 : Insulation resistance test (Clause no.9.7.2 of IS 60898(P-I)Test Conditions :

The humidity treatment is carried out in a humidity cabinet containingair with a relative humidity maintained between 91% - 95%.

The temperature of the air in which the sample is placed is maintainedwithin ± 1°C of any convenient value T between 20°C and 30°C.Beforebeing placed in the humidity cabinet, the sample is brought totemperature between T and T+4°C. At present we are not carrying thispre conditioning as old humidity chamber has been scrapped.

Measure the insulation resistance at following positions:

a) With MCB in the open position

Between each pair of the terminals which are electrically connected togetherwhen the circuit-breaker is in the closed position, on each pole in turn.

b) With MCB in closed position

Wrap the insulated portion in metal foil. Between each pole in turn and theothers connected together.

94

c) With MCB in closed position

Wrap the insulated portion in metal foil. Between all poles connected togetherand the frame, including a metal foil in contact with the outer surface of theinternal enclosure of insulating material, if any.The insulation resistance shallbe not less than

i) 2 M ohm for the measurements according to items a) & b);ii) 5 M ohm for the other measurements.

5.2.1 : H. V. TEST (Clause no. 9.7.3 of IS 60898 (P-I)

Initially, not more than half the prescribed voltage is applied, then it israised to the full value within 5 s. Having frequency of 50 Hz is applied for 1minutes between the following parts.

a) With MCB in the open position

Apply the voltage 2 KV AC for 1 minute between each pair of the terminalswhich are electrically connected together when the circuit breaker is in theclosed position ,on each pole in turn.

b)With MCB in closed position

Wrap the insulated portion in metal foil. Apply the voltage 2 KV AC for 1minute between each pole in turn and the others connected together.

c)With MCB in closed positionWrap the insulated portion in metal foil. Apply the voltage 2 KV AC for 1

minute between all poles connected together and the frame, including metalfoil in contact with the outer surface of the internal enclosure of insulatingmaterial, if any.No flashover or breakdown shall occur.

5.3 Test of Temperature rise & Measurement of power loss(Clause no.9.8 of IS 60898(P-I)) :

5.3.1 Perform the temperature rise test on 3 nos of samples as perAnnexure C, Table C.2 of IS 60898 part1/2002.

5.3.2 Connect all 3 samples of MCBs with single phase loadingtransformer in series using connecting cable size as per table 9 of IS60898(P-I)/2002. Note down the room temperature during lastquarter of test period.

5.3.3 Inject the rated current with MCBs in closed Position.5.3.4 After the steady-state value measure the temperature at

i) Terminals for external connections.Temperature-rise shall not exceed the limiting values specified intable no.6 of IS 60898(P-I).ii)Measure the mili volt drop across MCB and multiply it with the

rated current to get wattloss per pole and it should be as per tableno.15 of IS 60898 (P-I)/2002.

5.3.5 Resampling if required/permitted is to be carried out as per TableC.2 of IS 60898 (P-I)/2002.

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5.4 : TIME CURRENT CHARACTERISICS AT 1.13 TIMESOF RATED CURRENT( Clause no 9.10.1.1 of IS 60898(P-I)/2002)

5.4.1 Perform the Time current characteristics on 3 nos of samples asper Annexure C, Table C.2 of IS 60898 part1/2002.

5.4.2 Connect the MCB with required size of wire as per Table 9 of IS60898(P-I)/2002 across the terminals of loading transformer. Startthe auto transformer .Test should be conducted in cold condition(Term “cold” means without prior loading)

5.4.3 Set the current equal to 1.13 times of rated current by varying thevariac of loading transformer. MCB should not trip within 1 hour forMCB up to and including 63 A. (2 hours for above 63 A.)

5.4.4: TIME CURRENT CHARACTERISICS AT 1.45 TIMESOF RATED CURRENT( Clause no 9.10.1.1 of IS 60898(P-I)/2002 )

This test is to be immediately followed by the above test.(1.13 Non trip test)Rest of the procedure is same as aboveSet the current equal to 1.45 times the rated current within 5s.MCB should trip within 1 hour for MCB up to and including63 A.(2 hours for above 63 A.)

5.4.5 : OVER CURRENT TRIPPING AT 2.55 TIMES OFRATED CURRENT( Clause no 9.10.1.2 of IS 60898(P-I)/2002)Test should be conducted in cold condition(Term “cold” meanswithout prior loading) on samples of test 5.4.1 & 5.4.4

Rest of the procedure is same as aboveSet the current equal to 2.55 times the rated current .MCB should trip within 1 minute*.*(60 Sec. for rated currents up to and including 32 A120 Sec. for rated currents greater than 32 A.)

5.4.6 Resampling if required/permitted is to be carried out as per Table C.2of IS 60898 (P-I)/2002.

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MCCB1. Objective Testing of MCCB.


Loading transformer, 0-5 KV HV Test Set, Tong tester,Hygrometer, Multimeter , Thermocouple with sensor, Cables.


4. Reference IS 60947 ( Part I ) / 2007 & IS 60947( Part II)/2003 , IS 60898(Part I) : 2002.

5. Procedure5.1 Sampling : Table C.2 of annexure C of IS 60898(P-I)/2002

3 Piece per lot.

5.2 Test to be conducted :

1. Dielectric test ( Cl. 8.3.3.4.1) of IS 60947 ( Part- I , Table-12A)

2. Temperature rise test at rated current. (Cl. 7.2.2) of IS60947 ( Part- II, Table -7)

3. Time current characteristics at 1.05 times of rated current(Cl. 7.2.1.2.4) of IS 60947( Part- II , Table 6 )

4. Time current characteristics at 1.30 times of rated current(Cl. 7.2.1.2.4) of IS 60947( Part- II , Table 6 )

5.3 Atmospheric condition : As per IS 60947 Part I Cl.no.6.1.3.1: The relative humidity of the air does not exceed 50% at a maximum temperature of 40°C. Higher relativehumidities may be permitted at lower temperature, e.g. 90%at +20ºC.

5.4 Dielectric test: Cl.no 8.3.3.4.1 of IS 60947(P-I Table -12 A)

A test voltage of substantially sinusoidal wave form of valueas specified in IS 60947 part I table 12A (Dielectric testvoltage corresponding to the rated insulation voltage). havingfrequency of 50 HZ is applied for 5 seconds between thefollowing parts:

a) Between all the terminals of the main circuit connectedtogether (including the control & auxillary circuits connectedto the main circuit ) and the enclosure or mounting plate,with contacts in all normal position of operations.

b) Between each pole of the main circuit and other polesconnected together and to the enclosure or mounting plate,with contacts in all normal position of operations.

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c) There shall be no unintentional disruptive discharge duringthe test.

5.5 Temperature rise test : At rated current. (Cl. 7.2.2) of IS60947 ( Part- II, Table -7)

5.5.1 Connect MCCB with single phase loading transformerconnecting all poles in series using the cables of suitablesize. The equipment shall be mounted as specified in 8.3.2.1and shall be protected against external heating or cooling.

5.5.2 As specified in clause no 8.3.3.3.4 IS 60947 ( Part-I)depending on values of test current following testconnection arrangement shall be used:

i) For values of test current up to and including 400A :

a) The connections shall be single core, PVC insulated, Cuconductor with cross sections as given in table 9.

b) The connections shall be in free air and spaced atapproximately the distance existing between the terminals.

ii) For values of test current higher than 400A but not exceeding800A :

a) The connections shall be single core, PVC insulated, Cuconductors with cross-sectional area as given in table-10 orthe equivalent Cu bars given in table 11.

b) The connections specified in ii a) shall be spaced atapproximately the same distance as that between theterminals. Multiple parallel conductors per terminal shall bebunched together and arranged with approximately 10 mmair space between each other. Multiple Cu bars per terminalshall be spaced at a distance approximately equal to the barthickness. If the sizes stated for the bars are not suitable forthe terminals, or are not available other bars havingapproximately the same cross-sections and approximatelythe same or smaller cooling areas may be used. Cuconductors or bars shall not be laminated.

5.5.3 For identification of phases put a mark like R,Y,B on upperside & r,y,b on lower side of spreader links of MCCB.

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5.5.4 Put marking on MCCB at:i) The terminal for external connection.ii) Parts intended to be touched but not hand held non

metallic point where temperature is to be recorded.iii) Record the initial temperature at each marked point.

5.5.5 Display the time duration on the blackboard placed in lab toconduct the test.

5.5.6 Inject the rated current with MCCB in ON Position.

5.5.7 As specified in clause no 8.3.3.3.1 of IS 60947 (Part-I)record the ambient air temperature during the last quarter ofthe test period by at least two thermometer orthermocouples, equally distributed around the equipment atabout half its height and at a distance of about 1m from theequipment. The temperature sensing means shall beprotected against air current, heat radiation and indicatingerrors due to rapid temperature changes.During the tests, ambient air temperature shall be between+10º C and 40º C and shall not vary by more than 10º C.

5.5.8 After the steady state value, measure & note down thetemperature at following marked position :

i) The terminal for external connection.ii) Parts intended to be touched but not hand held , non metallic

where marking is done.iii) Temperature rise shall not be more than 80°C for the

terminals of external connectioniv) Temperature rise shall not be more than 50°C for the parts

intended to be touched but not hand held nonmetallic.

5.6: Inverse time delay over current operation at 1.05 times ofrated current( Clause no 7.2.1.2.4 of IS 60947 ( P-II,Table 6 )

5.6.1 Connect the MCCB with proper size of cable across theterminals of loading transformer.

5.6.2 Display the time duration on the blackboard placed in lab toconduct the test..

5.6.3 Start the loading transformer & set the current throughMCCB equal to 1.05 times of rated current by varying thevariac of loading transformer & observe.

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5.6.4 MCCB should not trip within 2 hour after beginning of thetest.

5.7: Inverse time delay over current operation at 1.30 times ofrated current (Clause no7.2.1.24 of IS 60947 (P-II , Table 6)

5.7.1 This test is to be immediately followed by the test referredat 5.6 above.

5.7.2 Connect the MCCB with proper size of cable across theterminals of loading transformer.

5.7.3 Display the time duration on the blackboard placed in lab toconduct the test.

5.7.4 Start the loading transformer & set the current throughMCCB equal to 1.30 times of rated current by varying thevariac of loading transformer & observe.

5.7.5 MCCB should trip within 2 hour after beginning of the test.


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100

ELCB1.Objective Testing of ELCB

2. References IS 12640 part 1 / 2000


4. Apparatus/Materials

500v Megger, 0-5 KV HV test set , Oscilloscope, Sensitivity Panel

5. Procedure5.1 Sampling : Table A2 of annexure A of IS 12640

3 Piece per lot .If all three samples pass all the tests lot is acceptable.In case anyone sample fails in any of the four tests, repeat the tests on3 new samples. In these there should be no failure

5.2 : IR TEST: With 500 V megger : Clause no. 9.7.2 of IS 12640

1 . Measure insulation between operating parts when open .2. Measure Insulation between operating parts and body when closed.

Values thus obtained shall be more than 2 MΩ.

5.3 : HV TEST: Annexure D of IS 12640

Instrument: 0-5 KV HV test set:Keep ELCB on a metal frame used as body reference. Keep ELCB open

101

and connect one terminal (phase) of 0-5 kv HV test set to one pole ofELCB with reference plate and all other poles shortened together andconnected to other terminal of HV test set(neutral).Apply 1.5 KV for one minute by selecting time and voltage. Repeat thesame with each pole. No flashover or tripping should occur.

5.4 : VERIFICATION OF THE CORRECT OPERATION IN USE OF STEADY

INCREASE OF THE RESIDUAL CURRENT

5.4.1 Start the sensitivity panel and oscilloscope .5.4.2 Switch ON main MCB on sensitivity panel and adjust the voltage byvariac to 240 V.5.4.3 Keep the switch 2 & 3 on appropriate current range i.e. if ELCB has aleakage current of 30 mA , then keep these switches on 30 mA, & leakagecurrent is 100 mA , then keep these switches on 100 mA.5.4.4 Connect one pole of ELCB across the test object terminal 1&2.5.4.5 Switch on the current circuit MCB ( blue in color ) & start increasingcurrent gradually by varying appropriate potentiometer knob ( R1). &observe the tripping current and note down the same. ELCB should tripwithin 50% to 100% leakage current .5.4.6 Perform the test on each pole.

5.3 MEASUREMENT OF TRIPPING TIME AT RATED TRIPPING

CURRENT.

5.5.1 First 3 steps are same as 5.4.1 , 5.4.2 & 5.4.3.

5.3.2 Short the test object terminal 1 & 2 .

5.3.3 Switch ON the current circuit MCB ( blue in color ) and adjusttripping current ( as shown on sensitivity Test Display ) by varyingpotentio-meter knob R1 . Then switch OFF the current circuit MCB .

5.3.4 Connect one pole of ELCB under test across test object terminal 1 &2 and switch it ON.

5.3.5 Connect 1 Ω resistance across 5 & 6 terminals marked as “ SHUNTFOR SENSITIVITY TEST” .( Terminal 3 & 4 and 7 & 8 in shortedcondition. )

5.3.6 Connect the signal cord of oscilloscope across 1 Ω resistance.

5.5.7 Keep the switches at following position.1) Storage mode2) Roll mode3) Pre-trigger at 25%

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4) Normal mode (at trigger section)5) Select Channel (at trigger section)6) X1/X10 at X17) Press arm button. LED ( at arm/store) blinks & stops after

receiving trigger8) Volt/ div - 0.2/div9) Time / div - 20 m sec.

5.5.8 Now close the current circuit MCB , A set tripping current will flowthrough the shorted pole of ELCB. Within few millisecond ELCB willtrip and chopped waveform will appear on the screen of oscilloscope.Measure the time taken to operate the circuit.

Perform this test on each pole and measure time on each occasion.Maximum time shall be reported.

After testing on each pole switch OFF the current circuit MCB andthen only change the pole.

SENSITIVITY TEST ( Tripping Current passed)

Settings a) Volt / Div - 0.2V/divb) Time/div - 20 m sec.

Specified Value - 40 m sec. (max)Observed Value - 11.8 m sec.

WAVE FORM

11.8 m sec.( tripping time )

5.4 Measurement of Speed of Operation.

5.6.1 First four steps are same i.e 5.5.1 & 5.5.25.6.2 Switch ON the current circuit MCB ( blue in color ) and adjust the

current five times the rated tripping current by varying knob R3.5.6.3 Same as 5.5.4.5.6.4 Connect 1 Ω resistance across 7 & 8 terminals marked as SHUNTFOR SPEED OF OPERATION TEST” terminals.

103

5.6.5 Keep 3&4 and 5&6 short by shorting links.Rest of the procedure is same.

SPEED OF OPERATION ( 5 Times tripping Current passed)Settings a) Volt / Div - 0.1V/div

b) Time/div - 20 m sec.

Specified Value - 200 m sec. (max)Observed Value - 21.2 m sec.

21.2 m sec WAVE FORM

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PAINT

1. Objective Testing of Paint2. Apparatus/ material

Flow cup, Flat Brush, Acetonemetal panels of 01.25m mild steel plate150X 150 mm in size.Weighing Balance, counter weight of 100 gms. Scratch hardnessmachine, Flexibility and adhesion apparatus .


4. Reference IS 2339/1993, IS 101/1961

5. Procedure5.1 Sampling: One tin set per lot ( minimum 1 liter )

( As per practice in MTS department )Different types of paints are received for testing.

Coal Tar Black ( Anti Corrosion )Paint epoxy black

IS 290 / 1961

Silver enamel GreyEnamel PinkPaint enamel Golden Yellow

IS 2932 /1979

Red Oxide Zinc ChromateSynthetic Zinc Phosphate( Grey )

IS 2074 / 1979

Paint Stoving Enamel IS 153/1990

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Aluminum Paint with Paste IS 2339/ 1963

Procedure for Testing Aluminum Paint with Paste is givenbelow:

5.2 INTRODUCTION:The ready mixed paint obtained by mixing the material inthe two chambers is used for protective and decorativepurposes, particularly where a heat reflecting surface isrequired. The ready mixed paint shall be obtained bymixing aluminum paste and a varnish medium contained inseparate chambers of the dual container.

Requirements for aluminum paint for general purposes, in dualcontainer are given below:

CHARACTERISTICS REQUIREMENTDrying time Not more than 8 hoursConsistency Smooth and uniform and

suitable for brushing orspraying

Finish Lustrous and smoothFlexibility and Adhesion No visible damage,

detachment or cracking ofthe film.

Weight per 10 Liters. InKg.

Minimum weight in Kg/10liters of material is 9.0.

5.4 PREPARATION OF METAL PANELS:All metal panels shall be of 1.25 mm mild steel plate, freefrom surface imperfections, such as rolling marks, scoresetc. or 0.315 mm (30 SWG) tinned mild steel plate and shallbe 150X 100 mm in size.Before use the mild steel panels, freed from mill scale byany suitable means, shall be adequately rubbed with steel

105

wool or coarse emery and cleaned with petroleumhydrocarbon solvent or any other suitable solvent. Rustand signs of corrosion shall be removed with flint paper ofIS Grit NO. 100 after which the panel shall be rinse withbenzene and wiped dry with a clean rag. Tinned mild steelpanel shall be cleaned with suitable solvent and shall beroughened with flint paper of IS Grit No. 100 after whichthe panels shall be rinsed with benzene and wiped dry witha clean rag.

5.5 APPLICATION:Ready mixed paints shall be applied by brushing orspraying as specified in the material specification.

5.6 Brushing: ( cl. 6.2 of IS 101/ 1964 )Flat brush used in the preparation of test panels shall beclean, free from loose hair and shall be of suitable size.The material shall be applied by brushing to obtain an evenand uniform coat and shall not be poured or spilled uponthe panel.

5.7 DRYING TIME: ( cl. No. 7 of 101 /1964 )The material shall be brushed on a 150 X 150 mm mildsteel panel prepared in the manner described in accordancewith 5.4 and allowed to air dry. Under followinglaboratory drying condition.

5.8 Air drying : ( cl. No. 7.3.1 ) All drying tests shall beconducted at room temperature and relative humidity of 65+/- 5% in a well ventilated chamber, free from draughts anddust and film expose to diffused daylight for at least 6 hoursin each 24 hours of drying period, care being taken toprotect it from direct sunlight. The procedure of test on thedried film of the panel after specified period is as follows:-Place the panel in one pan of a suitable balance andcounterpoise it with weights. Place a further weight of 2.25Kg and press on the dried film surface of the panel with thethumb till the two pans are balanced. Hold for one minuteand then slowly release. No sign of stickiness to the thumbshall be apparent and the thumb impression, if produced,shall be such as can be wiped away with dry cotton wool.

5.9 CONSISTENCY: ( Cl. No. 4 )The consistency of the paint should be smooth and uniformand suitable for brushing or spraying as required. The cup,

106

generally known as Ford cup Viscometer No.4 is used forchecking the consistency of paint.

Place the ford cup on the stand in a place free fromdraughts, preferably with the air temperature within therange 30°C +/- 5°C. Level by the use of a spirit levelplaced on the rim. With the orifice closed by the finger, fillthe cup with the bubble free sample unit it just begins tooverflow into the gallery, pouring slowly to minimize theformation of air bubbles. If bubbles are present, allow themto rise and then remove them from the surface. Place thereceiver under the cup. Remove the finger watch the streamof liquid flowing from the orifice. The flow of paint throughford cup should be smooth and uniform. There should notbe a break of the stream into droplets unless and until theentire paint has drained out.

5.10 FINISH: ( Cl. No. 7.5 of IS 101 /1964 )The paint, when applied on mild steel panel by brushing orspraying, whichever is specified and allowed to dry in avertical position. Under specified condition, shall dry tohard firmly adherent, flexible and smooth film, free fromsagging and wrinkling with a matt, semi glossy or glossysurface in accordance with the requirement of materialspecification. The film shall be examined not earlier than48 hours and not later than 100 hours after application. Thefilm so produced shall be of normal opacity and in no wayinferior to a film prepared in the same manner and at thesame time from the approved sample

5.11 FLEXIBILITY AND ADHESION(After 48 hrs of airdrying):- ( cl. No. 16 of IS 101 )Apply a coat of material by either brushing or spraying,whichever is specified to a 150 X 50 mm, 0.315 mm (or 30SWG) tinned plate prepared as described in 5.4. Allow thepanel to air dry or stove on horizontal position for a periodas specified in a material specification. After air drying orstoving, bend the panel double, 75 mm from the upper edge,over a 6.25 mm diameter rod or as otherwise specified inmaterial specification in the special apparatus used fordetermining flexibility and adhesion with and the paint filmoutside. The time of bending shall not exceed one second.The paint film shall not show damage, detachment orcracking when examined under x 10 magnification.

5.12 WEIGHT PER 10 LTRS IN Kgs:-

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The calibrated cylinder or cup is filled with the material andweighed. A cylinder or cup which when filled up at roomtemperature holds 100 grams of water. Weigh the cylinderor cup when empty and then fill to the brim with the paint.Assuming that the volume of the contents is 100 ml,calculate and express as kg per 10 liters. The minimumweight in Kg/10 Ltrs. of the material when tested shall be asper respective IS.

5.13 Scratch Hardener Test: ( Cl. 15 of IS 101 /1964 )In this method resistance to scratching under a specific loadof a dried film of the paint is tested.Apply a coat of the material by either brush or sprayingwhichever is specified to a 150 x150 mm , 0.315 mm ( or 30SWG ) tinned plate prepared as described in para 5.4. Allowthe panel to air dry in a horizontal position for 48 hours underspecified drying condition or stove as specified in materialspecification. Test the panel under a load of 1000 gm unlessotherwise specified in the material specification. Fix theneedle at the end of the counterpoise , which is kepthorizontal by adjusting the length of the needle and draw thepanel under the needle at a rate of 30 to 40 mm per second.A scratch showing the bare metal , shall not be producedwhen tested in this manner.


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TARPAULINE

1. Objective Testing of TARPULIN


Stand for Cone, Scissor, Bucket , Water,Weighing machine, Vernier, Scale,Liquid measuring Jar. Tensile machine, funnel , wire cone , glass rod


4. Reference Ref .- 1) IS – 2089 / 1977 (Amd. 1, Reaffirmed 1991)2) IS – 1424 / 1983 (Amd. 1, Reaffirmed 1989)3) IS – 1964 / 1970 (Reaffirmed 1988)4) IS – 1969 / 1985 (Amd. 1, Reaffirmed 1993)5) IS – 6899 / 19846) IS – 7903 / 1984

5. Procedure 5.1 Sampling: Clause 6.2 and 6.1

Nos. of rolls in the lot Nos. of rolls to beselected

Permissible Numberof defective rolls

Up to 25 3 025 to 50 5 051 to 100 8 0101 to 300 13 1301 and above 20 1

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5.2 WEIGHT PER SQ. METER(Ref :- Table 1 of IS :- 6899 / 1984)Test sample size :- Out swatches of 250 +/- 2 mm x fullwidth of fabric including selvedges.

TEST PROCEDURE

5.2.1 Prior to test, the test sample shall be conditioned in the standardatmosphere of 65 +/- 2 % RH & 27 +/- 2 0C temp.

5.2.2 Determine weight of conditioned test sample to an accuracy 0.5 g.5.2.3 Determine the length & width of test sample.5.2.4 Calculate the weight in g/sq mtr, = W x105

A x BWhere ;W = weight of specimen in kg,A = length of fabric in m = 0.25 mtr.B = width of fabric in cm.

5.2.5 Similarly ,calculate at least four test sample & determine theaverage of all the values.

5.3 BREAKING STRENGTHTest sample size :- strip size :- 5 x 20 cm raveled strip.Ref. Cl. 8.2.3 of IS 1969 / 1985, reaffirmed 1999)Mount the test sample centrally in the jaws of the tensile machinewith the longitudinal threads parallel to the direction of theapplication of the load after pre – tensioning.

Calculation :- calculate the mean breaking load.L = L1

nwhere : L = mean br. load

L 1 = sum of the observed values of brawledn = no. of observation

5.3 CONE TEST(Ref. Cl 3.3.7.2 of IS :- 2089 – 1977)

Formation of cone :- Form a cone without creasing the folds witha 300 x 300 mm piece. Prepare at least 3 test specimen.

Test Procedure :- As per clause 5,6,7, 8 & of 7941/1976Suspend the cone on an open metal conical ring frame so thatcondensed moister on the other surface of cone does not affect thetest & fill the cone with 400 ml of water & allow it to stand as suchin conditioned room at 27 +/- 2C & 65 +/- 2 % RH for 18 hrs.Examine for leakage & wetness & after 18 hours.

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Test result :- There shall be no leakage of water either through the apex ofthe cone or through the outer surface which is exposed to air inconditioned room. The outer exposed surface shall also not get wet.

NOTE :- Water drops due to condensation inside the fold of cone or alongthe contact line with the metal ring should not be considered for rejection.

5.4 COLOUR(Ref tender spec.)

For variety no. 4: - GreyFor variety no. 2: - BrownFor variety no. 5: - Test specifies


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LUGS/ FERULES

1. Objective Testing of Copper / Aluminum Lugs/Ferrules


Conductivity meter, Vernier caliper, Pres bench


4. Reference IS 8309/1993BEST specifications, Latest approved drawings

5. Procedure 5.1 : Sampling : 1 0 randomly selected samples per lot.( As per practice in MTS department )

5.2: Dimensional analysisMeasure all the lugs/ ferules for dimensions as per latest approved

drawing (BEST specification / Table 1 or 2 of IS 8309 ) with thehelp of vernier caliper. There shall be knurling on inner surface andentry should be barrel mouthed.

5.9 Flattening test : ( Cl. No. 8.2 of IS 8309 )

Take any one of the randomly selected sample . Place the test piecebetween two plane , parallel rigid platens extending over length notmore than 75% of the barrel. Apply a gradually increasing load untilthe internal surfaces are in contact over at least half of the internalwidth of the flattened test piece. At the end , observe if there is any

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crack. Reject if any crack is seen.

5.10 Conductivity : ( Cl. No. 8.2 of IS 8309 )

Take the flattened sample for measurement of conductivity as youwill get sufficient flat surface needed for measuring conductivity.*Keep this sample as it is for at least one hour so that it will reachambient temperature. Measure the conductivity as defined in the BusBar chapter. ( or refer manual of conductivity meter )* In case of lugs of sizes above 70 sq. mm. measurement ofconductivity is possible on flat portion of lugs without flattening thesample. In such case measure conductivity for all 10 samples.Conductivity of Aluminum Lugs/ Ferrules shall not be less than 60 %IAS.


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GLANDS

1. Objective TESTING OF GLANDS OF DIFFERENT SIZES

2. Apparatus/ material Vernier caliper, weighing machine ( 30 Kgs.)


4. ReferenceBEST specifications, Latest approved drawings

5. Procedure 5.1 : Sampling : 10 randomly selected samples per lot.( As per practice in MTS department )

5.2: Dimensional analysisGlands are used for holding/ supporting multi core cables in LVboards/ Distribution pillars. They should be free from burs andscratches.Measure all the glands for dimensions as per latest approved

drawing with the help of vernier caliper. Check all the nut bolts /stud for fixing /tightening.

5.3 Measure the weight of all the glands on conventional weighingmachine.

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BAKELITE SHEET

1. Objective Testing of Bakelite Sheets ( P3 type )


0-30 KV HV Test Set, Verneir caliper , scale, Oil Tub, Beaker,Electronic weighing machine


4. Reference IS-2036

5. Procedure 5.1 Sampling: ( Table 8 of IS- 2036 )

Lot size No. of samples

Upto 150 3

151 to 500 4

501 & above 5

Bakelite Sheet of grade P3 possesses very good electricalproperties even under humid conditions, relatively low waterabsorption and good machining and hot punching properties. It issuitable for high tension electrical applications at powerfrequencies. In BEST Undertaking bakelite sheet having nominalthickness of 1.6mm, 3.2mm, 2.5mm and 6.5mm are used.

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Following tests are carried out on Bakelite sheet of grade P3 inM.T.S. Laboratory as per the Indian Standards.

- Thickness of sheet in mm- (Cl.No.5.3, table no.3 of IS-2036)

- High Voltage Test (Flat wise)- (Table no. 6 of IS 2036)

- Water absorption in mg corrected at 20’c (table no. 5 of IS2036)

5.2 Thickness of sheet in mm: (As per Clause 5.3 of IS 2036)

The thickness should be measured with the help of suitablemicrometer or digital vernier caliper at ten points equally spacedaround the edges of the sheets and their mean value should be takenas the thickness of the sheet. The specified values of nominalthickness alongwith the tolerances given in table no.3 of IS 2036 isreproduced below:-

Bakelite Sheet with nominalthickness

Permissible Variation in mm.

1.6 mm +/- 0.14

2.5 mm +/- 0.18

3.0 mm +/- 0.20

6.5 mm +/- 0.39

5.3 Conditioning of the test specimen:-

Test specimen shall be subjected to an atmosphere of 65+/- 5percent relative humidity at a temperature of 270C +/-20C for notless than 24 hrs. Every specimen shall be tested as soon as possibleafter removal from the controlled atmosphere, and in any case, thetest shall be started before three minutes have elapsed.

5.4 High Voltage Test:- (As per Clause 5.6 of IS 2036)

There are two methods to test the Bakelite sheet for HighVoltage Test viz. flatwise and edgewise. Test specimenhaving nominal thickness of upto 5mm, 1.6mm, 2.5mm and3.2 mm) should be subjected to flatwise test whereas test

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specimen having nominal thickness of above 5mm(6.5mm) should be subjected to edgewise test.

5.4.1 High Voltage Test (Flatwise):-

This test is applicable to Bakelite sheet having nominalthickness of 1.6 mm, 2.5mm and 3.2 mm.

Specimen:

Prepare at least two test specimen of size 100mm x 100mm square.The electrodes used shall consist of a solid cylinder of brass. Theupper electrode shall consist of a solid cylinder of brass 40mm indiameter and approximately 40 mm in height. The lower electrodeshall be brass block 80mm in diameter and approximately 25mm inheight. The sharp edge of electrodes in contact with the specimenshall be rounded to a radius of not more than 1mm.

5.4.1.1 Test Procedure:-

Before actual testing for high voltage test condition the testspecimen as mentioned in para 5.3 above . Place the test specimenin between the electrodes and immerse the whole assembly in aninsulating oil. Maintain the temperature of oil at 900C+/- 20C withthe specimen and electrodes immersed, for a period of half to onehour, after which apply an alternating voltage of frequency 50 +/- 5Hz between the electrodes. Start with a voltage one third of thespecified proof stress and increase at the rate of approximately 1KV per second to the specified proof stress. Maintain the proofstress for one minute. The material shall be taken to have passedthe test if there is no electrical breakdown at the specified proofvoltage. The specified proof voltages for the bakellite sheet havingvarious nominal, thickness given in table 6 of IS 2036/1974 isreproduced below:-

Bakelite Sheet with nominalthickness

Specified proof voltage

1.6 mm 15 KVAC

2.5 mm 18.5 KVAC

3.2 MM 21 KVAC

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5.4.2 High Voltage Test (Edge wise):-

This test is applicable to sheets over 5 mm thick. Prepare atleasttwo test specimen of size 100mm length & 25 mm width. Thethickness of the specimen shall be that of the sheet under test.Finish the edges of the specimen that are in contact with theelectrodes truly as parallel planes at right angles to the surface ofthe material, and remove any sharp corners. Two metal plates,preferably of brass, of sufficient – size to cover the edges of thespecimen should be used as a electrodes. Before carryout the HighVoltage test the test specimens should be conditioned as mentionedin para 5.3 above.

5.4.2.1 Test Procedure:-

Place the conditioned test specimen in between the electrodesand immerse the whole assembly in an insulating oil. Maintain thetemperature of oil at 900C +/- 20C with the specimen and electrodesimmersed for a period of half to one hour, after which apply analternating voltage of frequency 50+/- 5 cycles per secondsbetween the electrodes. Start with a voltage one third of thespecified proof stress (i.e. 20 KVAC min for a Bakelite sheet ofnominal thickness of 6.5mm of grade P3) and increase at the rate ofapproximately 1 KV per second to the specified proof stress.Maintain the proof stress for one minute. The material shall betaken to have passed the test if there is no electrical breakdownwith test specimen at the specified proof voltage.

5.8 Test for Water Absorption in milligrams: corrected at20°C: ( Cl. No. 5.6 and table 5 of IS – 2036 )

Cut from the sheet the test specimen 38.0 + 0.5/-0.0 mmsquare. The thickness of the specimen shall be the thickness of thesheet under test. Smoothen the edges of the specimen with no. 0of glass paper. Condition the test specimen at explained in para 5.3.

5.5.1 Test Procedure:Weigh the specimen to the nearest milligram and immerse for

a period of 24+/- 1 Hrs in distilled water at temperature between200C to 300C which shall not be vary by more than +/- 20C. Onremoval from water, wipe dry the exposed surfaces with blottingpaper or clean cloth. Re-weigh the specimen to the nearestmilligram and complete the weighing within two minutes of theremoval of the specimen from water. Record the increase in weightin milligrams.

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When the test has been carried out at an immersion temperaturehigher than 200C, calculate the equivalent water absorption at 200Cby applying the correction factor given below:-Water immersion Temperaturein 0C

Correction Factor

200C 1.0

210C 1.05

220C 1.10

230C 1.15

240C 1.20

250C 1.25

260C 1.30

270C 1.35

280C 1.40

290C 1.45

300C 1.50

Report this as the water absorption for the specimen under test at200C. The water absorption in milligrams corrected at 200C forthe bakellite sheet of various thickness of grade P3 as given in tableNo. 5 of IS 2036 is reproduced below:-

Nominal Thickness in mm Water absorption in mg(max)

1.6mm 76 mg

2.5mm 85mg

3.2 mm 90 mg

6.5 mm 118 mg


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SYNTHETIC MAT

1. Objective Testing of Synthetic Mat of size


0-50 KV HV Test Set, Tensile Machine, Dumbbell shaped Die ,Vernier Caliper, oil bath, bras electrodes of 75mm and 25 mm dia


4. Reference BEST Specification 1920108 ( or latest ) IS 15652/ 2006

5. Procedure 5.1 Sampling: One Sheet per Lot( As per practice in MTS department )

Test to be carried out Clause No.

Thickness of Mat ---------- 3.3Tensile strength ---------- 3.4.1Elongation ---------- 3.4Insulation Resistance ---------- 3.5.1Leakage current test ---------- 3.5.2Breakdown Test ---------- 3.5.3Dielectric Strength ---------- 3.5.4

5.2 Thickness of Mat : ( as per clause no. 6.3 of IS 15652 )Measure the thickness of the mat with the help of vernier

caliper at minimum 5 places length wise as well as breadthwise at uniform distance. Record the mean value.

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5.3 Insulation Resistance: ( as per clause no. 8.2.1 of IS 15652 )When tested with 500 volt megger insulation between twoelectrodes ( kept above and below the mat ) should show valueabove 100,000 MΩ.

5.4 AC proof volt test : ( as per clause no. 8.2.4 of IS 15652 )A solid brass cylinder of size 75 mm is placed below centre ofthe sample piece( 1.270m x 1.270m ) . Another solid brasscylinder of size 25mm is placed above mat exactly in themiddle of bottom cylinder.

Connect the HV probe of 0-50 KV HV test set to uppercylinder and the earthing probe to lower cylinder. A voltage of36 KV ( in case off 33 KV mat & 22 KV in case of 11 KVmat) is applied for 3 minutes. No breakdown or flashovershall be observed.

5.5 Leakage current test: ( as per clause no. 8.2.2 of IS 15652 )After completing AC proof volt test switch OFF the HV test

set and connect a Multi-meter ( showing current in micro &mili –ampere ) in series with HV probe. Apply the ratedvoltage and observe the leakage current in multi-meter. Itshould be less than 10mA.

5.9 Dielectric Strength : ( as per clause no. 8.2.3 of IS 15652 )Test piece in size of 150mm x 150mm shall be immersed ininsulating oil at ambient temperature.Method is same as that of AC proof volt test. However voltageis to be increased gradually to 65 KV in case of 33KV mat, andupto 45 KV in case of 11 KV mat. The electric strength shallbe the highest voltage which is with stood for 20 secondswithout breakdown.

5.10 Tensile strength & elongation : ( as per clause no. 8.1 ofIS 15652 )Four dumb-bell shaped piece shall be prepared in accordancewith IS 10810 (part 7). Before the tensile test 10 mm lengthshall be marked by the two lines centrally on each specimen.The rate of separation of jaws ( grips) shall be 250+ 50mm/min. The tensile strength and elongation at break shall bedetermined simultaneously on the same test pieces. During the

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test the distance between the marker lines shall be closelyfollowed and the elongation shall be determined by measuringthe distance between the two marker lines at the instant ofbreak, based on the original gauge length. The breaking load atwhich the test piece breaks is also recorded for each piece.

Calculation:

A = w x t ( width x thickness )

Tensile strength in N /mm2= F / A ( F = Force in Kgf)

Elongation at break ( in percent )

= G2-G1 x 100G1

Where G1 = original gauge lengthG2 = gauge length at break

5.11 Tensile strength & elongation after immersion of testspecimen in oil for 48 hours.:( as per clause no. 8.5 of IS 15652 )

Four numbers of dumb-bell shaped specimen are preparedand immersed in transformer oil for 48 hours. After removingfrom oil clean the specimen with tissue paper and repeat thetests prescribed in para 5.8. The value thus obtained for thesesamples shall not be less than 80 % of the corresponding valuesobtained in test carried out on samples from same batchwithout conditioning.


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HAND GLOVES

1. Objective Testing of Hand Gloves


Testing is to be done by Minimum T-8 grade officer.

3.Responsibility

HV Test Set , Rishabh mili-ammeter, water tub, vernier caliperDial Gauge

4. Reference IS – 4770 / 1991, IS – 5424 / 1969 & IS – 2584 / 1963

5. Procedure 5.1 Sampling :

One pair per lot( As per practice in MTS department )

5.2) PHYSICAL INSPECTION

1. Check the condition of the hand gloves. They should be ingood condition.

2. The colour should be as per specification

5.3) H.V.Test AT 5KV

Ref: 1. Annex F & Cl. 5.8 & Table 3 of IS 4770 : 1991Procedure as per of Clause 2.6.1 of IS 5424 : 1969 & IS2584 :1963

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5.3.1 Before the commencement of test clean the cuffs of thegloves with alcohol in order to prevent flashover occurringthrough water seeping along the chalked surfaces.

I) Hold the hand glove in position by means of holding stand /insulating clips . Immerse hand glove in tap water (27 +20C) up to 40 mm from the edge of the cuff & fill with tapwater up to the same level. Leave it for conditioning in thisway for a period 1 hour before test .

II) The water inside & outside of the glove forms the internal& external electrode respectively.

III) Insert the phase electrode inside the hand glove . Take carethat this electrode does not touch the surface of the handglove and electrode is centrally located in hand glove

IV) Insert the earth electrode in water outside the hand glove.V) Raise the potential applied across the test electrode from

zero to 5KV as rapidly as is consistent with its value beingobserved in the measuring instrument but not less than 1KV per second.

VI) No breakdown or flashover shall be observed within1minute.

5.4) LEAKAGE CURRENT TESTAnnex F & of IS 4770, 1991 Table 31) Repeat steps i) , ii) , iii) , iv) , v) , vi) as mentioned in Sr. No.

5.3 above. And Then :1) Connect the earth electrode in series with mili-ammeter &

insert the extended lead in water outside the hand glove.2) Test the hand glove for the leakage current of 5KV & maintain

this voltage for 1 minute .The hand glove shall not pass a current more than 4milli-

amp (as per table 3 of IS 4770) during the test for 15 seconds.

5.5 Breakdown Voltage: Cl. 5.9 and table 4 of IS 4770Connection is same as that for HV test . Apply test voltage

at 10 % BDV of the glove and increase it at a rate of 1 KV persecond until breakdown occurs. Or until 1.2 times the expectedbreakdown voltage has been reached.Record the maximum voltage observed at breakdown.

5.6 Thickness of non crotch area: Cl. No 5.5 and table 1 of IS4770Measure the thickness of each glove at not less than 4 pointsat the back and 4 points on the fore part of the palm. Takealso measurements at 1 or more point in thew crotch between

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thumb and index finger and in the crotches between thefingers. The thickness measured shall fall within themaximum and minimum limits specified in table 1.

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GUM BOOT

1 . Objective Testing of Gum Boot

2 . Responsibility Testing is to be done by Minimum T-5 grade staff.

2. Apparatus/Material

HV Test Set , Rishabh miliammeter

3. References IS – 4770 / 1991, IS – 5424 / 1969 & IS – 2584 / 1963

5. Procedure 5.1 Sampling: One pair per lot( As per practice in MTS department )

5.2) PHYSICAL INSPECTION

1 Check the condition of the boot. They should be in goodcondition.

2 Check the no. of the gumboot.3. The colour should be black.4. Check for bright finish , rubber sole & whether inside cotton

lining is provided or not.

5.3) H.V.Test AT 5KV

Ref: 1. Annex F & Table 3 of IS 4770 : 19912. Procedure as per of Clause 2.6.1 of IS 5424 : 1969 &

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IS 2584 :1963

5.3.1 Clean gum boot before the commencement of test withalcohol in order to prevent flashover occurring through waterseeping along the chalked surfaces.

5.3.2 Hold the Gum boot in position by means of holding stand/ insulating clips . Immerse Gum boot in tap water (27 + 20C)up to 40 mm from the edge of the cuff & fill with tap waterthe same level .Leave it for conditioning in this way for aperiod of 1 hour before test .

5.3.3 The water inside & outside of the boot forms the internal& external electrode respectively.

5.3.4 Insert the phase electrode inside the gumboot . Take carethat this electrode does not touch the surface of the gumbootsand electrode is centrally located in gumboot.

5.3.5 Insert the earth electrode in water outside the gumboot.

5.3.6 Raise the potential applied across the test electrode fromzero to 5KV as rapidly as is consistent with it’s value beingobserved in the measuring instrument but not less than 1 KVper second.The Gum Boot shall withstand it without breakdown .

5.4 LEAKAGE CURRENT TEST

Annex F of IS 4770, 1991 Table 3 of 11

1) Repeat steps i) , ii) , iii) , iv) , v) , vi) as mentioned in Sr. No.5.3 above.

3) Connect the earth electrode in series with mili-ammeter &insert it in water outside the gumboot.

4) Test the Gum Boot for the leakage current of 5KV & maintainthis voltage for 1 minute .The Gum Boot shall not pass a current more than 4milli-amp(as per table 3 of IS 4770) during the last 15 seconds.

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SAFETY SHOES

1. Objective TESTING OF SAFETY SHOES


0-30 KV HV Test set


4. Reference IS – 5424 / 1969 Sp. For rubber mats for Elect. PurposeIS – 2584 / 1963 Method of test for electric strength of solid insulatingmaterials at power frequencies.

5. Procedure 5.1 : Sampling : 1 pair per lot( As per practice in MTS department )

TEST CONDUCTED

1) Physical Inspection2) H.V. Test3) Leakage current test


5.21 Check the condition of the shoes they should be in goodcondition.

5.2.2 Check the no. of shoes & colour. Colour should be as specifiedin the tender.

5.3 : H . V . TEST

Procedure :- cl – 5.1.2 of IS 2584 / 1963.Spec. Value – 15 kv / 1 min. ( cl – 2.6.1 of IS 5424 / 1969)

Equipment / accessories – 0.30 kv H.V. test set(high 15 mm minimum)- electrode of 75 mm dia. & electrode of(height 25mm minimum) – 25 mm dia (brass electrodes).

5.3.1 Place the 25 mm electrode inside the shoes near hill area & 75mm electrode from outside the shoes so that hill area of shoewill be in between these electrodes. Ensure that electrode areplaced centrally.

5.3.2 Phase probe of H.V. test set is connected to 25mm electrode &earth probe of H.V. Test set connected to 75 mm electrode.

5.3.3 Switch ‘ON’ the H.V. Test set & H.V. Supply & raise the

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voltage to the required value of 15kv as rapidly as possible.Maintain this voltage for 1 minute. There should be no punctureor disruptive discharge.

5.4 : LEAKAGE CURRENT TEST : ( cl – 2.6.1 of IS 5424 / 1969)

Equipment / accessories - 0.30 kv H.V. test setMulti meter with micro-ammeter range.

5.4.1 Place the 25 mm electrode inside the shoes near hill area & 75mm electrode from outside the shoes in series with multi-meterso that hill area of shoe will be in between these electrodes.Ensure that electrode are placed centrally.

5.4.3 Switch ‘ON’ the H.V. test set & raise voltage to requiredvalue of 15kv as rapidly as possible & measure the leakagecurrent shown in micro-ammeter. The leakage current shall notexceed 160 MA / M 2 (calculated on the area of smallerelectrode) for any position of the electrodes.

Diameter of smaller electrode = 25 mm

Area of smaller electrode = 3.142 x (0.025)2

4= 4.9087 x (10) -4 sq.meter

If the leakage current shown in micro-ammeter is 65 µ A then theleakage current in MA /M2 is given as.

Leakage current MA / M2 = 65 x10-3

4.9087 x (10)-4

= 65 x (10)-3 x (10)4

4.9087

= 132.42 MA / M2


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CORK SHEET

1. Objective Testing of Cork Sheet


Tensile Machine , Micro-meter, Mandrill, Scale


4. Reference IS-4253( P-II) / 1968

5. Procedure 5.1 Sampling: 1 Sample per lot.

5.2 Dimension Analysis:Thickness : ( As per clause no. 3.1 of IS )Clean the cork sheet with a piece of cloth. Measure the

thickness with Micro-meter at not less than four points.The measurement shall fall within 10% of the specified value.

5.2 Tensile strength : ( As per clause no. 7.4 of IS )Three samples of size 25mm x 100mm to be cut with

sharp knife or die to give clean cutting edges.There shall be at least 30 mm grip in each chuck. The rate

of traverse of jaws shall be 30 + /- 3 cm /min. Load shall beapplied and tensile strength is calculated in kPa. It shouldbreak away from chuck. ( 1 Kgf/cm2= 98.0665 kPa )The value of tensile strength shall not be less than that definedin the Table 1 of IS-4253.

5.3 Flexibility Test : ( As per clause no. 7.7 of IS )Three specimen of 25mm x 180 mm shall be cut from widelydifferent positions.The specimen shall be bend 1800 on mandrill of size 3timesthe thickness of cork for 3mm thick and 4 times the thicknessfor size above 3mm. There shall be no breakage or separationof granules.If any of the test specimen fails then a complete retest withanother set of specimen shall be carried out and the materialshall be deemed to comply only if all these test specimensshow no breakage.


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HV breakdown voltage of Transformer Oil ( B.D. Value)

1. Objective Testing of Transformer oil for determination of HV breakdownvoltage


High Voltage ( BD Value ) Test Set ( Prayog Make )

3.Responsibility If only BD values are to be measured, testing is to be done byminimum T-5 grade staff.But If new oil is to be tested for all parameters then it should betested by minimum T-8 grade officer.

4. Reference IS 335-1993 ( for new oil )IS -1866-2000 ( for processed oil )

5. Procedure 5.1 Sampling: ( as per IS 6855 -1973 )Nos. of drums in a batch( 209 liters each )

Nos. of drums from whichsample is to be taken

2 to 5 26 to 20 321 to 50 451 to 100 5101 to 200 6

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201 to 400 8401 to above 10

IMPORTANT : Samples once brought shall be used for all sixtests. HV test for BD value shall be done on the same day.

N.B. All sample are to be tested for BD valuesand Tan Delta . All other tests are to be performed oncomposite solution.

5.2 Taking of oil samples from drums.Samples are to be taken in amber colour bottles with the help ofburette specially purchased for this purpose.

5.2.1 Clean the burette with cleaning cloth.5.2.2 Draw oil from drum with the help of burette and rinse the

burette 2-3 times with the oil of the drum from whichsample is to be taken.

5.2.3 In next attempt pour the oil in bottle and rinse the bottleas well.

5.2.4 Take the sample in next attempt and keep the bottles airtight.

5.3 Procedure : Table 1 of IS – 335 & IS 67925.3.1 Check the gap between electrode by using gauge provided .

5.3.2 Before starting the test, oil cell should be cleaned by rinsingit twice with the oil under test.

5.3.3 The sample should be poured in the oil cell 1 cm aboveelectrode, slowly to avoid any bubble formation.

( the axis of the electrode shall immersed to a depth ofapprox. 40mm. in oil )

5.3.4 The temperature of oil should be same as that of ambienttemperature.

5.3.5 Allow the sample to settle for 5 minutes.5.3.6 If air bubbles are not observed Close the cell cover. Switch

ON the supply, and increase the voltage at the rate of 2 KV perseconds. ( in our system it is done automatic )

5.3.7 The indicator stops at test result when breakdown occurs.Note down the reading

5.3.8 The first application of the voltage is made as quickly aspossible after the cell has been filled provided there are no

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longer any air bubbles in the oil or at the least 10 minutes afterfilling. After each breakdown the oil is gently stirred so as tokeep away the carbon particles between the electrodes,avoiding as far as possible the production of air bubbles. Forthe subsequent five tests , the voltage is re-applied one minuteafter the disappearance of any air bubbles that may have beenformed. If the observation of the disappearance of air bubblesis not possible , it is necessary to wait for five minutes before anew breakdown test is started.

5.3.9 The electric strength shall be arithmetic mean of the sixresults which have been obtained.

6. Test Report Combined report consisting all six test results is to be prepared oncomputer.

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Measurement of Dielectric Dissipation Factor (Tan Delta) oftransformer oil

1. Objective Testing of Transformer oil for measurement of DielectricDissipation Factor (Tan Delta)


SOKEN make Insulation Material Auto Schering Bridge ( EQP-127), Acetone , Oven, External digital thermometer, DigitalTemperature indicator & K type Thermocouple of Yokogawamake.


4. Reference Table 1 of IS-335 / 1993 & IS 6262 /1971

5. Procedure

N.B. All sample are to be tested for DielectricDissipation Factor (DDF).

This test is to be performed using SOKEN make ‘InsulationMaterial Auto Schering Bridge’. It consist of oil cell, heating

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chamber, temperature regulator, and main Comparator/ Bridge.

5.1 Maintain ambient temperature of 240C (Max) & RH 50 %apprx. During the test all the 3 air conditioner should bekept on.

5.2 Clean the oil cell (2-3 times) with acetone and keep it in theoven at 105oC for one hour.

5.3 Rinse the oil cell (2-3 times) with oil to be tested , and thenfill it up to the level marked in the cell.

5.4 Put the oil cell in heating chamber and connect the circuitas given in figure 1.

5.5 Switch ON the supply of heating coil i.e. I/P to temperaturecontrol unit.

5.6 In order to control temperature of oil which is kept insidecell up to 900C maximum following steps are to befollowed,

5.6.1 Temperature Control Unit is set at 750C to cut off or switchoff supply of heating coil. Insert K type thermocouplesensor in oil cell and connect it to the Temperature ControlUnit. Switch ON the Temperature control unit.

5.6.2 As soon as the temperature of the oil cell reaches 700C to750C remove K type of thermocouple sensor from oil cell.

5.6.3 Use another digital temperature indicator and thermocouplesensor to check temperature of the oil cell. Allow oil tocondition near 900C for around 30 min. Remove digitaltemperature indicator.

5.7 Connect main Comparator/ Insulation Material Auto ScheringBridge & oil cell for Dielectric Dissipation Factor (TanDelta) measurement. Switch ON measuringComparator/Bridge, increase the voltage up to 500V andnote down the reading of DDF on display.

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6. Test Report Combined test report consisting of all six test results is to beprepared on computer.

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TOTAL ACIDITY (TRANSFORMER OIL)

1. Objective TOTAL ACIDITY TEST PROCEDURE OF TRANSFORMER OILPORTABLE TEST KIT METHOD


1.0 Chemicals required:-

a) Rectified spirit (Ethyl Alcohol)b) 0.0085 N Sodium carbonate solution.c) Universal Indicator

2.1 Other Accessories:-a) Clean glass test tubes.b) Pipettesc) Colour chart/plate calibrated with neutralization number

values.3.Responsibility Testing is to be done by Minimum T-8 grade officer.

4. Reference IS-1866/1983 - Code of practice for maintenance and supervision ofmineral insulating Oil in the equipment. Annexure C of 1866( for usedoil )IS-1448(P-2)/1967 Part II – Methods of test for petroleum and itsproducts. For Acidity

5 Procedure N.B. Test to be performed on composite solution of all the samplespertaining to one lot.

Total Acidity - It is the measure of free organic and inorganic acidspresent together in the oil. It is expressed in terms of theno. of milligrams of Potassium Hydroxide (KOH)required to neutralize the total free acids in one gram of the oil.

5.1 Preparation of Sodium Carbonate Solution:- This solution isprepared by dissolving 0.1183 gram of anhydrous sodiumcarbonate in 250 ml of distilled water in a suitable flask or beaker.Sodium carbonate solution should be prepared carefully. Thissolution has a life of three to four months after which it must bediscarded and fresh one shall be made.

5.2 Method of Test for total acidity of old transformer oil

5.2.1 Take 1.1 ml oil (under test) is pipette in a clean dry test tube.5.2.2 Add 1 ml of ethyl alcohol and shake well.5.2.3 Add 1 ml of 0.0085 N sodium carbonate solution – shake well

5.2.4 Add five drops of the universal indicator.

The resulting mixture develops a colour depending on the pHvalue of the mixture. Compare the colour of the mixture withthe colour plate and note down the correspondingneutralization number (mg KOH/g).

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5.3 Method of Test for total acidity of New transformer oil

Apparatus :-250 ml conical flask100 ml measuring cylinderBurette & pipette

REAGENTS :-Toluene – Conforming to IS 1839Rectified spirit-95%(v/v) Conforming to IS 323 (Absolute Alcohol)Alkali Blue 6B IndicatorStandard Hydrochloric Acid – 0.1 NStandard Alcoholic Potassium Hydroxide Solution – 0.02 N (KOH)Oil sample – Under Test

5.3.1 Take 60 ml tolune and 40 ml absolute alcohol into a flask.5.3.2 Add 1-3 ml blue 6B Indicator and a drop of HCL to sensitize

the indicator -----blue colour5.3.3 Neutralize the blue colour mixture with 0.02 N KOH. Do not

stop at the preliminary purple-red colour. Stop neutralization atstrong wine red colour.

5.3.4 Now add 100 ml oil sample and dissolve by swirling. Thecolour changes to purple blue.

5.3.5 Titrate the purple blue mixture with 0.02 N KOH.5.3.6 End point is reached when the purple blue colour changes into a

pronounced wine red colour which persists for 15 seconds.

CALCULATION :Calculate and express the result as the number of milligrams ofpotassium hydroxide required to neutralize the total acidity present inone gram of the oil sample under test.Total Acidity = 56.1 xVxN

WWhere.V=Volume is ml of KOH used in the titrationN=Normality of standard KOH=0.02NW=Weight in gram of the sample taken for the test

=volume taken in m X gram/cm3 (density)PRECAUTION :Do not prolong the titration as contamination with carbon dioxideappreciably affects the result.

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TOTAL ACIDITY VALUES :Old Oil KOH 0.5 mgKOH/gram(max)Table 1 ofIS 1866/1983New Oil 0.03 mg KOH/gram(max.)Table – 1 ofIS 335/1993

6. Test report Combined report consisting all six test results is to be prepared oncomputer.

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(PPM ) (TRANSFORMER OIL)

1. Objective TESTING OF DETERMINATION OF WATER CONTENT(PPM)


i) Main Unit – Veego/ Matic – IIIii) Beaker Assembly with Generator Electrode,

Teflon cover with ring and amber coloured beakeriii) Sensing Electrodeiv) Teflon Rotorv) Silica Gel cups (small and large)vi) Suitable syringes with needlesvii) Pipette with Rubber Bulbviii) Jar of sealantix) Glass funnelx) Constant voltage transformer (CVT)xi) Karl Fischer Reagentxii) Methanol (K.F. Grade specially dried less than

0.05%)


4. Reference IS –335:1993, IS-13567 / 1992, IS-6855:1973

5. Procedure 5.1 Sampling: Composite solution of all samples of each lot.

5.2 SCOPE :-

This method covers the procedure for determination ofwater content in oil in PPM with coulometrically generated karl-fischer reagent.

5.3 CHEMISTRY :-

Iodine generated by the electrolysis reacts with water.Iodine is generated in proportion to the quantity ofelectricity required in process of electrolysis. One mole ofIodine reacts with one mole of water, based on this principleit is possible to determine the amount of water directly fromthe quantity of electricity (Nos. of coulombs) required forthe electrolysis.

5.4 INTRODUCTION OF THE INSTRUMENT :-

The Veego/ Matic – III microprocessor based automaticanalyzer is designed for determination of moisture in varioussamples. It is based on specific and quantitative reaction ofwater with karl-fischer reagent. In this instrument, the reagentconsumed by the moisture in the sample is again electrically

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re-generated and the milligrams of moisture are displayeddirectly on the read out.

5.5 DESCRIPTION OF THE INSTRUMENTS :-

The Veego/ Matic – III incorporates the electroniccircuitary and the magnetic stirrer. The digital displaywhich shows the analytical results in milligrams of moistureis fitted on the front panel. Four lamps indicate varioussteps of titration. A keyboard consists of numeric keypadand various other function keys. A reset key is provided onthe rear panel.

5.6 VESSEL SOLUTION :-

Take about 40 ml of K/F reagent in a dry amber colouredvessel and add to it about 160 ml of K/F grade methanolcontaining moisture less than 0.05% and make up thevolume 200 ml.

5.7 GENERATOR SOLUTION :-

4/5 ml of above vessel solution before neutralization shouldbe added to the generator as generator solution.

5.8 NEUTRALIZING SOLUTION :-

Take 20 ml of K/F grade methanol containing moisture lessthan 0.05%. add to it approximately 0.4 ml of distilledwater. This can be used as neutralizing solution.

5.9 GLASS SYRINGES & SAMPLE STORAGE:-

5 ml syringes with needles of suitable diameter should beused. Blunt, square ended needles are preferred in order tominimize damage.Samples for water analysis should not be exposed to directsunlight. Between the time of collection and analysis thesamples should be kept in the dark. The time between thecollection & analysis should not be greater than 7 days.

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6.0 PROCEDURE :-

6.1 Add vessel solution in the vessel & generator solution in thegenerator electrode. Switch on the instrument. Put vesselin the hollow provided on the machine. Plug the twobanana plugs of the sensing electrodes to the sockets on themachine, Black to Black & Red to Red. Connect the smallthree pin connection to socket on the machine.

6.2 Add drop by drop neutralizing solution with the help ofsuitable syringe into vessel through the ventilating hole in

the Teflon stopper of the vessel. Add 2 to 3 drops of neutralizingsolution and wait for some time. Add neutralizing solution veryslowly & drop wise till the vessel solution becomes slightlytransparent. When the vessel solution is exactly neutralized, themessage ‘EXCESS WATER’ will be displayed indicating presenceof moisture in vessel solution. Now stop adding neutralizationsolution. Care should be taken that no excess of neutralizationsolution is added.

6.3 The excess of moisture added by the neutralizing solution willbe neutralized by iodine generated by generator electrode. Theprocess will continue for some time till the excess of water invessel, added through the neutralizing solution is fully titrated andneutralized. When moisture is completely neutralized message‘EXCESS WATER’ will disappear.

6.4 If large quantity of neutralizing solution is added much inexcess it will take a long time to complete this titration. Then bypressing the NEUT key the titration can be completedcomparatively in shorter time.

6.5 Stop the stirrer by STIRRER switch, swirl the vessel assemblyby lifting it from the hollow to little extent and again switch ‘ON’the stirrer. Allow the instrument to run for 10 to 15 minutes withoutadding any sample.

6.6 Maintain the generator solution level approximately 10 mmbelow the vessel solution.

6.7 The drift of the vessel solution is a measure of the dryness ormoisture freeness of the vessel solution. If the drift is low ,itindicates that the vessel solution is moisture free. To check the driftpress ‘Drift’ key. When the drift of the vessel solution is low (i.e.within 2 or 3 counts ), the instrument is ready for the sampletesting.

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6.8 This is an equilibrium stage. The vessel solution has neitherexcess Iodine nor excess water and is ready to detect the watercontent in a sample added to it.

6.9 Take 5 ml sample in syringe & keep it ready with air bubbleremoved. The syringe should be rinsed with the sample 2-3 timesto avoid water contamination.

6.10 Before adding oil sample, press ‘start’ key. Message ‘Inject’will appear on display, then add 5 ml of oil with the help of suitablesyringe into vessel solution through a hole provided for thepurpose. With this PPM process start and machine will give audiosignal when process completes.

6.11 To find out the ‘PPM’ of the sample, enter the quantity of oil(5 ml), density of oil (0.892) with the help of ‘SMPL’ and‘Density’ key.

6.12 By pressing the ‘PPM’ key, the water content in oil samplewill be displayed in PPM.

7.0 CLEANING OF ASSEMBLY :-After testing is complete, please refer instruction

manual for cleaning the accessories. Never use water toclean any accessories of the instrument. Methanol should beused for this purpose.

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Transformer oil (Flash Point)

1. Objective Testing of Transformer oil ( Flash Point )


The Pensky Marten flash point apparatus, Thermometer with theinstitute of the petroleum designation IP 16C to the requirement ofthe higher range , Heating arrangement ( Gas heated with gasregulator )


4. Reference IS 1448 ( P-21) : 1992

5. Procedure 5.1 Sampling: Composite solution of all samples of each lot.

5.2 Clean and dry all parts of the cup and its accessories thoroughlybefore stating the test. Fill the cup with oil to be tested up to thelevel marked.

5.3 Place the lid on the cup and insert the thermometer in its place.

5.4 Light and adjust the flame so that it is of the size of a bead of 4mm diameter.

5.5 Connect the 3 Pin plug to the A/C main and turn the sunviccontrol knob clockwise to the extreme point. The heaterindicating lamp will glow.

5.6 After few minutes put the sunvic control to such a position thatthe temperature of the sample to be tested in the cup increases 5deg. To 6 deg. Centigrade per minute.

5.7 Turn on the stirrer at 90-120 rpm. Apply the test flame whenthe temperature of the sample is 17 deg. Centigrade below the

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anticipated flash point of the sample turn the

5.8 Turn the shutter knob left in its lowered position for 1 sec andquickly raised to its high position clockwise so that the flame islowered into the vapour space of the cup in 0.5 sec, Do not stirthe sample while applying the flame.

5.9 If the sample is known to have flash point above 1100C, applythe test flame in a manner just described at each temperaturethat is multiple of 2’C beginning at a temperature of 18’C to28’C below the expected flash point.

5.10 Record as the flash point the temperature read on thethermometer at the time the test flame application causes adistinct flash in the interior of the cup. Do not confuse the trueflash point with the bluish halo that sometimes surrounds thetest flame at applications preceding the one that causes theactual flash.

5.11 The specified value of a flash point of a new insulation oilas per IS 335/1993 is 1400C (min.)

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Transformer oil VISCOSITY

1. Objective Testing of viscosity of transformer oil.


Viscometer, stop watch, Viscosity bath, Digital Temperature sensor withthermocouple Yokogawa make.

3.Responsibility Testing is to be done by minimum T-8 grade Officer.

4. Reference IS-335 , IS- 1448 ( PART 25) -1976 clause no. 6

5. Procedure5.1 Sampling: Composite solution of each lot is to be tested for

viscosity.

5.2 Method :

5.2.1 Fill the viscosity bath with distilled water up to level marked beforeapplying 230V AC, 50 Hz supply. Never start supply in dry conditionthis may damage heater. Always keep drain valve close while operation.

5.2.2 Start the viscosity bath & set the temperature at 27 0C. After setting thedesired temp. verify it with the calibrated Digital temperature sensor.

5.2.3 Clean the viscometer thoroughly by rinsing it with a appropriate solvent.Charge the viscometer with the oil sample through tube 1, in such amanner that the U –tube at the bottom fills completely without trappingair. Place the clean viscometer in the bath. In such a way that no anyportion of the oil sample in the viscometer be less than 2cm below thesurface of the bath.

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5.2.4 After the viscometer has reached temp. equilibrium at least 20 minutes at270C, place a finger over tube 3 and apply suction to tube 2 until theliquid reaches the centre of bulb D.( fig.2 in IS 1448 ).The oil is suckedup until its level is approximately 5 mm above the upper etched mark.Remove suction from tube 2. Remove the finger from tube 3, andimmediately place it over tube2 until the sample falls away from thelower end of the capillary. Remove the finger from tube 2 , and measurethe time for the bottom of the meniscus to pass from top edge of theupper timing mark to the top edge of lower timing mark.

5.3 Calculation :Calculate the kinematic viscosity v from the measured flow time and theinstrument constant C by means of the following equation:

v= C x t

where v = kinetic viscosity in centistrokes,C = calibrated constant of the viscometer in

centistrokes per second , and

t = flow time in seconds.

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COPPER WINDING WIRE1. Objective TESTING OF COPPER WINDING WIRE


Digital varnier , micro ohmmeter, Tensile machine


4. Reference IS NO.:- 13730 (Part 0 / sec1.) / 1993 Specification :- Tenderspecification

5. Procedure 5.1 Sampling : 1meter from each bundle5.2: DIAMETER OF CONDUCTERRef. Table 1 of IS 13730 / 1993i) Gauge of wire generally specified in inspection form. Find out the

diameter corresponding to the gauge no. Tolerance for diameter isgiven in table 1 of IS 13730 / 1993. Measure the diameter by vernier& note down the diameter. Diameter is to be measured after removingthe enamel coating.

5.3 : MESUREMENT OF RESISTANCERef. Table D1 of IS 13730 (P-0, sec1) 1993Equipment :- 4 channel micro ohmmeter with probes.i) Switch ‘ON’ the micro ohm meter & keep it ‘ON’ for at least 20

minutes.

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ii) Cut the sample piece of 60 cm length.iii) On both the ends remove the enamel coating up to 8 cm.iv) Fix the wire on the half meter marked resistance stand,v) Connect the potential probes (in base conductor) at a distance of 50

cm length & connect the current probes on both the outer ends.vi) Select the proper range on the micro ohmmeter & note down the

reading & the room temperature.vii) Calculate the resistance of conductor in Ω / m at 20 C as follows.

R x 2 x ( Temp. cor. Factor )= Resist in Ω/m

Procedure for removing enamel coatingSince the enamel is flammable. Apply light flame. When the enamel getscompletely burnt with help of cotton wipe out the ashes of the enamel sothat the clean conductor is visible. Take care that conductor does not getdamaged.If specified value for required gauge is not available then the nearest

lower and upper value should be reported.

5.7 : PERCENTAGE ELONGATION OF WIRERef. Table 4 of Is 13730 (Part 0, sec.1) / 1993

Equipment :- Tensile machine5.7.1 Cut the test sample of 30 cm in length.5.7.2 Adjust the constant speed of traverse to 30 cm / minute.5.7.3 Adjust the length on the tensile machine to 20 cm (test

length).5.7.4 Keep the range on 100 kgf.5.7.5 Fix the sample piece in the jaws of the tensile machine.5.7.6 Press the “down” button of the tensile machine & observe

the length at the break. Wire should break at the centre. Thefinal length is the length at break.

5.7.7 Express the elongation at break in %.

Calculation = Final length – Initial length x 100Initial length

6. Test report Printed format

148

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G.I. WIRE

1. Objective Testing of G.I. WIRE

2. Apparatus

/ material

Weighing Machine, Stripping solution, Copper Sulphate solution,Glass container, vernier caliper


4. Reference IS 4826/1979, IS 6745-1972 )

5. Procedure 5.1 Sampling:One meter piece from any randomly selected coil.

5.2 Dimension analysis :

Check the number of strand in wire and also measure thedia of each strand.

5.3 Mass of zinc coating (Clause NO. 4.1 of 4826):

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Mass of zinc coating in accordance to IS 6745-1972 ( massshould be as per Table 1 of IS 4826:1979)

Specified value : 1 ) 270gm/m2 for 55 sq.mm

2 ) 60 gm/ m2 for 16 sq.mm.

Procedure: (STRIPPING METHOD)

5.3.1 Preparation of Stripping solution (Clause 5.1 of IS 6745)Dissolve 20g of antimony trioxide (sb203) in 1000ml ofconcentrated hydrochloric acid (specific gravity 1.16)

5.3.2 Immediately before test, prepare the stripping solution byadding 5 ml of the solution prepared in (5.2.1) to 100ml ofconcentrated hydrochloric acid (specific gravity 1.16). Mixwell.

5.4 Procedure:-

Weigh the clean test piece (600mm long) to 0.01 g. Whenthe test piece is too long for the container, it shall be eitherbent or coiled to permit complete immersion in the testsolution (or cut in a pieces of 6cm length). When theevolution hydrogen ceases or a few bubbles are beingevolved, take out the test piece, wash in running water,wipe off well with clean soft cotton cloth, fully dry andweigh again to within the nearest 0.01 g. Then measure thediameter to 0.01 mm at two places at right angles to eachother of the same location to obtain the average value.Calculate the mass of coating in g/m2 using the formulaunder 1.2.1.

Note 1 : The time required for stripping will vary with thecoating thickness but should not exceed one minute.

5.4.1 Calculation:

M= M1-M2 X d X 1965

M2

Where

M= Mass of zinc coating in g/m2 of surface.

M1= Original mass in g of the test piece,

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M2= Mass in g of the stripped test piece, and

D= diameter of the stripped test piece in mm.

5.5 Uniformity of zinc coating (Clause No. 4.2 of IS4826/1979)

(No. of dips as per Table I of IS 4826:1979)

Copper Sulphate solution (As per Clause 3.1 of IS2633/1986)

5.5.1 Preparation:

Dissolve about 36 g of technical grade copper sulphatecrystals in 100 ml of distilled water. Heat the water to aidsolution, but if heated, the solution should be cooled beforeneutralizing.

5.5.2 Volume of Solution:

Test Piece (of 150mm length) of wire shall be testedin a glass container of at least 50mm inside diameter for2.00 mm wires and smaller and with at least 75 mm insidediameter for wires of more than 2.00 mm in diameter. Thecontainer shall be filled with fresh test solution to a depthof at least 100 mm. This quantity of solution shall be usedfor simultaneous testing one to seven test pieces. Thesolution shall be discarded after completion of the test andfresh solution used for any additional tests.

5.5.5 Procedure: ( 3 dips of 1 minute and 1 dip of half minutefor 55 sq.mm.And 1 dip of half minute for 16sq.mm G.I. wires)

The clean test piece shall be subjected to as many oneminute and half minute dips as prescribed in the relevantstandard, in copper sulphate solution kept at a temperatureof 18 +/- 2’C. Half minute dips shall be carried out aftercompletion of all the one minute dips. If possible, immersethe test piece completely, taking care that they do not toucheach other. During the test, neither the test pieces not thesolution shall be agitated. After each dip, withdraw the test

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pieces, rinse immediately in clean running water. Removeany black deposit including holes and pockets by a suitablebrush. Wipe and dry the test pieces with a clean soft clothand return immediately to solution.

Successive dips of one-minute each shall be continued, withwashing and wiping of the test pieces after each dip until thetest pieces have withstood the required number of dips oruntil the end point has been reached.

5.5.4 The material passes this test if at the end of the specifiednumber of dips, when the test piece is finally rinsed andwiped dry, it does not show any adherent red deposit ofcopper upon the base metal. In case of wire, any reddeposit of copper within 25 mm of the cut end of thesample shall not be interpreted as a failure of the sample.


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FUSE WIRE

1. Objective Testing of Fuse Wire

2. Apparatus

/ material

Micro gauge, Loading Transformer, Suitable size of base


4. Reference IS 9926 / 1981 , IS 2086 /1993BEST specification

5. Procedure 5.1 Sampling:Lot SizeNos. of spools

n1 n2 n1+n2 C1 C2 C3

Up to 150 5 5 10 0 2 2151 to 500 8 8 16 0 2 2501 to 1000 13 13 26 0 2 21001 to 3000 20 20 40 0 3 43001 and above 32 32 64 1 4 5

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Test to be carried out :1.0 Visual examination2.0 Dimensional Check3.0 Resistance Test4.0 Non Fusing Test5.0 Fusing Test

5.3 Visual Examination : Samples selected at random shallvisually examined for the following:The fuse wire shall be circular & shall have a uniform cross-

section & free from pits.The tin coating layer shall be uniform , smooth, continuous &firmly adherent to the base copper material.

5.4 Dimensional check : The diameter of fuse wire shall bechecked for compliance with the values given in the col. 2 & 3of table 1 of IS 9926-1981

5.5 Resistance Test : The measurement of resistance of wire shallbe carried out as per the procedure given in ‘Winding wire’chapter with the help of micro-ohm meter.

5.6 Specified value should be as per table 1 of IS 9926

5.7 Non – Fusing Test : ( cl. 3.4 of of 2086/1993 )5.7.1 Connect the wire in suitable size of cut-out and

connect the same to loading transformer.

5.7.2 Inject 1.6 times the rated current.

5.7.3 It should not blow in 30 minutes.

5.8 Fusing Test : ( cl. 3.4 of of 2086/1993 )

5.8.1 Continue with the set up of non fusing test, andincrease the current to 1.9 times the rated current.

5.8.2 Wire should blow within 30 minutes

N. B. Presently Fusing and Non-fusing tests are not being done as percircular from ……..

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PLASTIC PUTTY

1. Objective Testing of Plastic Putty


Penetro-meter, Digital weighing balance, Torque wrench , Stopwatch,


4. Reference Specification No. – Mts/Std.-14/0302, July 84.

5. Procedure 5.1 Sampling: One set (packet) per lot. ( 1Kg. )

Plastic putty is used as sealing agent. It is used temporarilyto attend oil leakages from transformers & containers.Plastic putty is also used to provide water resistant barrier

154

between soil water and insulating material of a cable jointand cable termination.Plastic putty is a set of two epoxy based cold settingcomponents. The putty set consists of,a) Resin &b) Hardener

The resin and hardener is supplied separately in soft solidstate in equal ratio. The resin & hardener shall havedistinguishing colours. After mixing the resin and hardenerthoroughly, the mixing shall be of uniform colour.Tests:-The following tests are carried out on plastic putty which isa mixture of its components resin & hardener.a) Hardening Timeb) Water absorption &c) Adhesive property

5.2 Hardening Time:- ( 3.2.1 of specs.)The resin & hardener which is supplied in equal ratio ismixed thoroughly. A small flat test piece of minimum 5mm thickness is prepared, keep is for cold hard setting andjust start the stop watch. After ten minutes, checkpenetration using Penetrometer. Go on checkingpenetration in two minutes interval. The mixture shall bedeemed to have hardened when its penetration numberreduces to 2. One penetration number is equal to 1/10th

mm.( Specified hardening time is 20 + 5 minutes )

5.3 Water absorption Test:- ( 3.3.1 of specs )5.3.1 Prepare preferably two spheres of about 25mm diameter

using the mixture prepared as in 5.2 . Generally it becomeshard after 25-30 minutes. For better & accurate result weighthe spheres after one hour and immerse in water. After 24hours take out the spheres from water and dry the surfacesusing blotting paper. Weigh the spheres and calculate thepercentage water absorption using the formula.

W2-W1--------- X 100,

W1

Where

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W1= Weight before immersion in water.W2= Weight after 24 hours immersed in water.

The specified water absorption is 0.2% maximum.

After 24 hours, when the sphere is kept on the pan of aweighing balance, it‘s weight start reducing due toevaporation of absorbed water. Therefore the weightobserved immediately after keeping the sphere on theweighing balance should be recorded.

5.4 Adhesion Test:-

5.4.1 One M.S. container & one M.s. rod are required foradhesion test.

5.4.2 M.S. container:- This shall be of 40mm, square base, openat one end with 20mm height. The base shall have a 14 mdia hole at the center.

5.4.3 M.S. rod:- This shall be of 16mm dia with a hexagonal headat one end & 13 mm dia at other end, just to insert into thehole of the M.S. Container.

5.4.4 Test Procedure:-

The rod is held in the container in such a way that one endfits into the hole of the container. The mixture of thecomponents resin and hardener is mixed thoroughly inequal ratio and filled into the container so as to totallyoccupy the space between the container walls and rod up toa height of 20 mm, in flush with the wall. The mixture setin this condition is allowed to remain for 24 hours. After 24hours, the container is held in a bench vice with the rodvertical and head upwards. A fixed torque of 3 kg-m isapplied on the hexagonal head of the rod by means of atorque wrench. There shall be no angular movement of therod.

156


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SWITCH FUSE UNIT/ICTPN1. Objective TESTING OF SWITCH FUSE UNIT/ICTPN


1 phase loading transformer, thermocouple based temperature indicator,milivoltmeter (multimeter with mv range),or bus bars, digital currentindicator, cable of proper size, spanners, screwdrivers, torque wrench,tong tester.

3.Responsibility Testing is to be done by Minimum T-5 grade staff.4. Reference IS No.:- 13947 (P I & PIII) / 1993

IS No.:- 13703 (P I & PIII) / 1993Respective latest approved drawing

5. Procedure5.1 : Sampling: 1 Sample per lot ( as per practice in MTS dept. )

TEST CONDUCTED

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1) Temperature rise test at rated current.2) Measurement of watt loss at rated current at steady state

temperature.3) Test for dielectric properties.4) Dimensional analysis.5) Physical inspection.

5.2: TEMPERATURE RISE TEST AND WATT LOSS OFFUSE

cl. 8.3.3.1 of 13947 (PIII) / 19935.2.1 Connect the switch fuse unit with proper size of cable or busbar.

SIZE OF SFU SIZE OF AL CABLEOR BUS BAR

FUSE SIZE

200 A 150 sq.mm aluminumsingle core

200 A HRC fuse(blade contact)

400 A 300 sq.mm aluminumsingle core


630 A 10x64 sq.mmaluminum single bus

bar or 8x40 double busbar


5.2.2 Make the connections to single phase loading transformerwith proper size of cable or bus bar (aluminum) as specified &with proper size of nuts & bolts provided by manufacturer.Connections should be such that, milivolt drop at rated current ofSFU at SFU bus bar & connecting cable or bus bar should bewell within 10 mv.

5.2.3 The test shall be made for a time sufficient for the temperaturerise to reach a steady state value, but not exceeding 8 hours. It isassumed that a steady state is reach when the variation does notexceed 10C per hour.

(we generally measure the temperature rise after 4 hrs.)Multiply the milivolt drop by rated current flowing through

SFU. This will give the watt loss of fuse. Maximum of the 3 fusesshall be recorded.

RATED CURRENT MARK WATT LOSS200 A 18 W315 A 28 W

630 48 W

5.2.4 Measure the temperature at all lower & upper terminals

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temperature at handle, temperature at metallic body at this note downthe room in temperature.

Temperature rise at respective parts should not be more than thevalues given in table II & IIIof IS 13947 (P.I).

PARTS MAX. TEMP. RISETerminals 65 0C

Handle (non metallic) 250CHandle (metallic) 15 0C

Part intended to be touched butnot hand held (body)

300C

5.3: TEST OF DIELECTRIC PROPERTIESClause no. 8.3.3.2 Table X of 13947 (P III)5.3.1a) With main contact closed.

The test voltage of 2.5 kv (as per table x of 13947 (PIII) shall beapplied for 1 minute.1) Between all live parts of all poles connected together & the

frame of the equipment (earth).2) Between each pole & all the other poles connected to frame of

the equipment (earth).5.3.2b) With the main contacts open.

1) Between all live parts of all poles connected together & the frameof the equipment (earth).

2) Between the terminals of one side connected together & theterminals of the other side connected together and earthed.

The test is considered to have been passed if there is no breakdown orflash over.

5.4 : DIMENSIONAL ANALYSIS

Following dimensioning are to checked

a) Overall length.b) Overall width.c) Overall height.d) Distance between wall mounting plate edge to fixing hole centre.e) Distance between wall mounting plate fixing bolt centre of the

enclosure & edge of the mounting plate.f) Length of extended bus bar from body.g) Cross section of bus bar.

159

h) Conductivity of bus bar.i) Thickness of bakelite sheet.


j) There shall be no damage to SFU, SFU bus bar, bus bars should bestraight, no damage to handle, bakelite lining should be fixed as perdrawing, mounting plate should be of adequate thickness. Fuse ofproper size should be used of reputed manufacturer. ‘ON’, ‘OFF’direction should be marked and defeat screw shall be provided. Nutbolt shall be of proper size.

ii) Name plate shall contain following information.Rated voltage.Rated current.Ser. No. & manufactures name.Year of manufacture.IS No. shall be marked.

* For ICTPN, temperature rise test is carried out in same manner.ICTPNs which contain rewirable fuses are not to be tested for wattloss measurement of fuses . Dimensional analysis are not carriedout for ICTPN.


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DISTRIBUTION TRANSFORMER ( measurement of losses)

1. Objective Testing of distribution transformer (MEASUREMENT OF LOSSES)


Micro- ohm- meter , Delta make 3 phase power analyser (V-A-W meter),flexible jumpers ( Shorting links ), CTsLocation : Distribution Workshop ( Test Bay )


4. Reference IS 2026/2011 (part I)

IS 11171/1985

5 Procedure 5.1 : Sampling:

All new distribution transformers are tested for measurement of loses.

TESTS

Following 3 tests shall be conducted on each new distribution

160

transformer.

i Measurement of winding resistance

ii Measurement of no load loss

iii Measurement of full load loss

5.2: Measurement of winding resistance(clause10.2 of IS 2026 part I):-

Equipments required – Micro- ohm- meter(dual or single channel),

Prestige make of 0.05 accuracy class.

5.2.1 Keep the Micro-ohm-meter ON for atleast 20 minutes in discharge

mode and adjust the reading to zero on both channels, by

shorting the current and voltage terminals(crocodile clips).

5.2.2 Connect the voltage terminals to the inner end of the bus bars

followed by current terminals (crocodile clip). To measure the

winding resistances on the LV & HV sides simultaneously using

dual channel micro-ohm meter outgoing current terminals of one

winding (say RY) should be connected to the incoming of the next

winding (say ry).

5.2.3 Note down the temperature of the room surrounding the

transformer. To measure the resistance between any 2 terminals,

release the charge/discharge switch ( which gives reading in

released or measure mode and discharges when pressed -

discharging is necessary to avoid getting shock while touching the

crocodile clips) and note down the steady reading. After the

readings are noted, press the charge/discharge switch for

discharging.

5.2.4 Measure the phase to phase resistances on all the 3 sets of LV &HV (i.e. ry, yb & br and RY, YB & BR) terminals.

5.2.5 Calculate per phase resistance from the phase to phase measuredresistances and convert it at 750 C, as given below:-For HV side ( connection)

R per phase = ½ (RRY + RYB +RBR ) Ohm / phase

For LV side ( connection)

r per phase = 1/6000 ( rry + ryb +r br ) Ohm / phase

To convert resistance to 750 C

R per phase at 750C = R per phase at R.T.( 234.5+75/234.5+Rt.)

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Precautions - ensure that the HV & LV side bus bars are securely

connected to the palm connector of the transformer. Loose

connection will lead to wrong result (unnecessary higher resistance

values).

Do not remove the voltage crocodile clips unless the discharge

switch is released. Connect the current and voltage cord wires as

per the -V +V, -I +I markings on he micro-ohm meter to the

respective current and voltage terminals.

After After completion of the resistance measurement, switch off the meter and

keep the same in the carrying case provided, alongwith connecting chords

in the control room of transformer test lab.

5.3: No load loss measurement test:-

The test is to be conducted as per clause 10.5 of IS 2026 (part I).

Equipments/Accessories: (i)Delta make, 3 phase power analyser (V-A-W

meter), accuracy class – 0.5, the current range to be used during this

test is 1A of the meter(for better accuracy). If in any case the current

exceeds 1A on display panel then select 5A range of the meter.

(ii)3 Nos. of measuring CT with 50/5 ratio, 0.2 accuracy class & 7.5 VA.

(iii)Three phase voltage stabilizer ( 0 – 600 V) for constant incoming

voltage.

(iv)Three, single phase 0-600 V, 80 A, motor controlled, oil filled auto

transformers for adjusting the voltage during the no load test and short

circuit test to the transformer under test.

v)L.T. Panel comprising of 2 main switches of main MCCB of 400 A, 2

switch-fuse units of 200 A, 3 phase contactor and MCCB.

PROCEDURE :

5.3.1

During this test HV winding is kept open and rated 415 V supply with

due frequency correction is given to LV winding.

5.3.2

Connect the earthing to the earthing terminal of transformer. Before

conducting the electrical tests ensure by inspecting that it is free from

physical defects (such as oil leakage, level of oil in the conservator etc.)

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and that the LV bus bar connections are tight.

5.3.3

Connect the 70sqmm stranded copper conductor flexible cable from LT

panel to LV phase bus bars of transformer.(Neutral should be kept open)

5.3.4

Switch ON, SFU1, SFU2 (marked as “ for O.C ” ), voltage stabiliser,

MCCB. The indicating lamps on all the 3 autotransformers will glow.

5.3.5

Close the door of transformer test bay and aske one Nawghany to guard

the door to prevent entry of any unauthorise person when the testing is in

progress. If possible lock the entry door.

5.3.6 Go to the control room and switch ON the 3 phase power analyser,

where the voltmeter and ammeter have 2 ranges viz., line to line and

phase voltage. Current range connections for 1A and 5A are provided on

the back side of the power analyser. Ensure that the selector switch

provided for this purpose is on line to line voltage range. For no load test

1A range is normally selected. If during this test current on the 3 phase

power analyser, exceeds one ampere, bring the voltages to zero and

change the current range to 5A.

2.8 Check all the connections of the 3 phase power analyser are tight and as

per the connection diagram.

5.3.7

Three switches for control motors are provided to vary the output

voltages of the 3 autotransformers. Upward movement of the switches

increases the output voltage and vice versa. These switches in fact rotate

the synchronous motors, which further rotates, the variable tap of the

autotransformer.

5.3.8

Adjust the line to line voltage to 415 Volt if the supply frequency is 50

Hz. As the no load losses are frequency dependant, the voltage must be

frequency corrected one, as per the chart*.

*A chart of corrected voltage against each frequency values is displayed

near Power Analyser for ready reference.

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5.3.9 When the voltages, currents and wattages become steady on the

display, press the “Hold” button and note the following readings:

i)Frequency

ii)3 Voltages

iiii)3 Currents &

iv) 3 Wattages. Take such 6 different readings

5.3.10 Calculate the no load loss of each reading using the following

formula :

No load loss = (WR + WY + WB ) X Frequency correction factorX

CT ratio X meter multiplying factor(mf)

Meter multiplying factor = 1 for 1 A range of Wattmeter

= 5 for 5 A range of Wattmeter

Frequency correction factor = 25/Test Frequency + 1250/ (Test

Frequency)2

5.4 Measurement of Full Load Loss:-

The test is to be conducted as per clause 10.4 of IS 2026/Part I. The

equipments and accessories to be used for this test will be same as those

for the measurement of no load loss test except that the 400 A main switch

(marked as “for S.C.”), MCCB & contactor in the LT panel are required

to be switched on. Also flexible jumpers made up of copper foils are

required to be used for shorting of the LV busbar of the transformer. The

CT ratio to be used during the test be commensurate with the primary side

full load current (KVA rating) of the transformer under test as given in the

table below:-

KVARating

Primary sidefull loadcurrent inAmps.

Value of thecurrent inAmps to beadjusted on3 phasepoweranalyser

CT Ratioto be

selected

No.offlexiblejumpersrequired

forshortingthe LVBusbars

630 33.1 0.6 50/5 4995 52.1 0.9 50/5 6

1600 84 0.8 100/5 8

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5.4.1 Short the three LV busbars using required number of flexible

jumpers depending on the KVA rating of the transformer under

test as given in the table above. Flexible jumpers are to be

connected with brass nuts, bolts and washers. Two holes are

provided on the flexible jumpers corresponding to the two holes

on the LV bus-bar. Secure the jumper on the LV bus bars using

both the holes. If both the holes are not matching, then the

losses would increase as the flexible jumper can be connected

using only one nut bolt. Ensure that all these connections are

tight.

5.4.2 Connect the 70 sqmm stranded flexible copper conductor cable

from LT panel to the R, Y & B HV terminals of transformer.

5.4.3 Connect the earthing provided in transformer testing bay to

the earthing terminal of transformer under test.

5.4.4 Switch ON the 400 Amps main switch (marked as “only for

S.C.”). Then switch ON the MCCB. The indicating lamps on

all three auto transformers will glow.

5.4.5 Close the door of transformer test bay and post one Nawghany

near the door to prevent entry of any unauthorised person while

the testing is in progress. If possible lock the entry door.

5.4.6 Go to the control room where the 3 phase power analyser is

already in ON condition. Change the connections on back side of

the power analyser from 1A to 5A range. Keep the 1A/5A switch

on 5A for selecting the desired range of the power analyser. Also

confirm that voltage range selector switch is on line to line

voltage.

5.4.7 When the contactor supply is switched ON for the first time,

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you will hear discrepancy buzzer. Acknowledge the buzzer by

pressing green push button and switch ON the contactor switch.

All the switches are on the old VAW panel. Check all the

connections of 3 phase power analyser are tight and as per the

connection diagram.

5.4.8 Adjust the line to line voltage such that current nearer to full

load value flows in both windings. Adjust the current to the values

given in above table, depending on the KVA rating of transformer

under test. Actual current that will flow during the test is as given

below:-

KVARating

PrimaryCurrent

Actual current during the test

630 33.1 0.6 x CT ratio X meter multiplyingfactor= 0.6 x 50/5 x 5= 30 Ampere

995 52.1 0.9 x CT ratio X meter multiplyingfactor= 0.9 x 50/5 x 5= 45 Ampere

1600 84 0.8 x CT ratio X meter multiplyingfactor= 0.8 x 100/5 x 5= 80 Ampere

5.4.9 After the voltages, currents and wattages become steady on the

display, press the “Hold” button and note the following readings:

i)Frequency

ii)3 Voltages

iii)3 Currents &

iv) 3 Wattages. Take such 3 different readings. Here first reading

is to be taken for calculations.

5.4.10 Reduce the voltages to zero by pressing voltage control

switches downward. Switch OFF the supply to the contactor and

the power analyser situated in control room.. In the transformer

testing bay, switch OFF the MCCB and 400A main switch marked

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“for S.C.”. Discharge the HV and LV terminals of the transformer

by discharge rod.

5.4.11 Disconnect the HV side cables and keep them at safe place.

Also remove flexible jumpers and place them on hangers provided

near the 3 phase voltage regulator. Remove earth connection.

Write “ M.T.S. Tested and date of testing ” on the transformer

using a chalk. Keep all the brass nuts, bolts and washers in the

aluminium box and keep this box along with spanners in the

transformer controal room. Switch OFF all the switches in the

transformer control room and then lock its door. Hand over the

key of this lock to OAMTS.

6.0 Calculations :-

An excel file is prepared for calculating the no load loss, full load loss and

% impedance with the help of readings noted during the tests. After

opening the file save the same with “save as ” menu with new transformer

sr.no. . On sheet no .1 of this file enters the readings of no load loss test.

This will give no load loss of all the six readings alongwith average no

load loss. Select the reading which is closer to the average no load loss

reading. On sheet 2 enter following transformer detail (i) Primary voltage,

(ii) Primary current, (iii) Secondary voltage, (iv) Secondary current, (v)

Guaranteed full load and no load loss, (vi) Percentage impedance quoted

& (vii) Type of cooling. Also enter the test certificate values or name

plate values of no load and full load loss and percentage impedance. Also

enter the HV & LV winding resistance (phase to phase), test room

temperature selected reading of no load loss measurement, first reading of

full load loss measurement. On page 2 enter MTL no. and MTL date, IF

no. and date, transformer sr.no. and its make, type, capacity and voltage

ratio. Three copies of report are to be printed.

7. Test report Report is to be prepared on computer as per para 6.0. and office copy to befiled in respective company’s file e.g. MTL-45 Crompton etc.

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ALUMINUM AND COPPER BUS BARS

1.Objective Testing of Aluminum and Copper Bus Bars

2.Apparatus/ material

Conductivity Meter ( Make Technofour) , Cleaning Solvent , 15 meterMeasuring Tape and Vernier Caliper

Check the calibration status of the equipment so as to ensure properfunctioning of the same .

3.Responsibility

Testing is to be done by Minimum T-5 grade staff.

4. Reference table 2 of IS :- 5082. For Conductivity of Aluminum bus bar in % IACSSpecified value is 55.cl :- 9.1 of IS-1897 / 1983 for Conductivity of Copper bus bar in % IACS(International Annealed Copper standard)

168

5.Procedure5.1 Sampling: Randomly select 10% ( nos. of bubars) per lot to bebrought from stores against memo. ( as per practice in MTS Dept. )

5.2 TEST PROCEDURE FOR CONDUCTIVITY OF BUS BAR

Clean the surface of the busbar under test with tolune, and keep the test piecesalong with the standard samples (Known conductivity plates) & equipmentfor at least 1 hour for the equalization of temperature. Hence, there shall be noneed to apply any temperature correction to the conductivity value obtained in% 1ACS.

Switch ‘ON’ the conductivity Meter & keep it in ‘ON’ position for at least20 minute for warm up.

After 20 minute of warm up time calibrate the conductivity meter withknown conductivity plates (provided with equipment) by placing theconductivity probe on these plates. One plate is of 22% of IACS conductivity& another is 99.5% of IACS conductivity. While calibration the conductivitymeter with lower conductivity plate (22% of 1 ACS) If the displayed readingis not 22% then adjust it to 22% by adjusting the low range adjustment knobon the conductivity meter. Similarly, while calibrating the conductivity meterwith higher conductivity plate (99.5 % of IACS) if the displayed reading isnot 99.5% then adjust it to 99.5% by adjusting the high range adjustmentknob on the conductivity meter. Confirm the calibration of the conductivitymeter for at least 5 times without adjusting any knob.

Now place the conductivity probe on the surface of the bus bar under test& insure that there is a proper contact between the conductivity probe & thetest piece surface & note down the reading. Take the readings at 4-5 places &the best one shall be reported.

5.3 TEST PROCEDURE FOR DIMENTIONAL ANALYSIS OF BUSBAR

i) Measure the length of the bus bar by 15m measuring tape.ii) Measure the width & thickness of the bus bar with the help on vernier

caliper.

The length, width & thickness are generally specified in tenderspecification.

iii) Recheck the calibration at the completion of actual measurement so as toensure proper functioning of the equipment .

169

6. Test report Format No. GENERAL/blankPrepared by:

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IGNITOR FOR 70/150/250/400 HPSV LAMP

1. Objective Testing of Ignitor for 70/150/250/400 HPSV Lamp


0-5 KV HV Test Set, 500 V Megger, DSO ( Digital Storage Oscilloscope ),Ballast , lamp of appropriate size, VAW Panel


4. Reference IS 12449 (PART 1&2), IS 9974 /1981(PART 1&2) or Latest version, BESTSpecification.

5. Procedure 5.1 Sampling: 2 Ignitors per Lot.

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5.2 Pulse characteristic :

5.2.1 Connect the lamp circuit using ignitor under test ,comprising DSO,VAW panel and a variac, with a standard ballast of respective size ( withoutlamp ) .Out put is to be connected to DSO through HV probe.

5.2.2 Switch ON supply and make DSO ‘ON’.Increase supply voltage gradually and note down the voltage at whichpulse appears on DSO.Increase the voltage to 198 V and note down the following parametersfrom the waveform:

171

A=Pulse heightB=√2 x Test Voltage Peak as specified in lamp data sheetC= A-BD=90% of AE=30% of CPulse width

Pulse PositionT1=Rise TimeT2= Duration time(as specified in lamp data sheet )Height of second peak

5.3 Restart the circuit with lamp connected. And observe :Weather second pulse is attained once the lamp is ignited.Shall not have any pulse attenuation within 3meters length of wire.Repeat the test with sample no.2

172

6. Test Report Report is to be prepared on computer.Prepared by:

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LV DISTRIBUTION PILLARS/LV BOARDS/MINI PILLAR

1. Objective Testing of LV Distribution pillars/LV Boards/ Street lighting pillars/Meter boards etc.


Conductivity meter, 0-5 H.V. test set, Loading transformer, Verniercaliper

173


4. Reference IS 5039/1983, IS 2086/1993, IS 5082/1981BEST SPECIFICATIONS / LATEST APPROVED DRAWINGS

5. Procedure 5.1 : Sampling : - One sample per lot.LV Distribution pillars/LV Boards/ Meter boards are initially received byworkshop . From where we receive only bus bars, ‘L’ bend & ‘Z’ bendetc. along with 2 fuse bases ( 630A ) for testing .

5.2 :- Testing of bus-bars : CL. No. 5.3.2, to 5.3.5 of BEST specs.)Bus bars, ‘L’ bends & ‘Z’ bends etc. are to be tested as individual fordimensional analysis and conductivity as per the procedure defined inBUS-BAR chapter. ( specified value is 52 to 58% IACS )

5.3:- Testing of fuse bases : ( CL. 5.4.5 of BEST specs. )Fuse bases ( 630 A ) are to tested as per the procedure prescribed inrespective chapter.

Compiled test report is to be prepared in printed format.


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STATIC ENERGY METERS.

1. Objective Testing of STATIC ENERGY METERS.


0-5 KV HV Test Set, 500 V Megger, Meter test bench, Aluminumfoil, aluminum bus bar, multi-meter

174

3.Responsibility Testing is to be done by minimum T-8 grade officer

4. Reference IS 13779 /1999 along with latest BEST specifications.

5. Procedure 5.1 Sampling: As per table 26 of ISLot size Sample sizeN N1 N2 N1+N2 C1 C2Upto 300 8 -- 8 0 0301 to 500 13 13 26 0 2501 to 1000 20 20 40 0 31000 and above 32 32 64 1 4

N1 = Size of the First Sample N2 = Size of the Second Sample

TESTS CONDUCTED ON IF SAMPLE METERS1) Insulation resistance Test (cl.11.7.6.4 of IS)2) Limits of errors (cl.11.1 of IS)3) Starting condition (cl.12.14 of IS)4) No load condition (cl.12.13 of IS)5) AC High voltage Test (cl.12.7.6.3 of IS)6) Power Consumption test (cl.12.7.1 of IS)7) Energy Registration (cl.12.15 of IS)

Additional tests conducted on TENDER SAMPLES1) Influence of Heating (cl.12.7.5 of IS)2) Repeatability of error (cl.12.17 of IS)

3) Accuracy and Energy registration at different tampercondition

a) One Phase reversalb) Two Phase reversalc) Three Phase reversal at UPF & 0.5 Lag PFd) One Phase failure 100% of Ibe) Two Phase failuref) Neutral disconnected

5.3 INSULATION RESISTANCE TEST :- (CL.12.7.6.4)

1) Wrap the meter with aluminum foil and keep it on aaluminum bus bar which will provide earth terminal.

2) Short all the current carrying terminals together.3) Measure the insulation resistance between above shorted

terminals and earth terminal ( bus bar in 1)with the help of

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500 V megger. Resistance should be more than 5 MΩ.

5.3 NO LOAD TEST (Cl.12.13)

i) Connect the meters on the testing bench with current circuit inseries with Zera(RSM) and potential circuit in parallel.ii) Switch “on’ the control panel and RSM (Zera)iii) Switch “ON’ the voltage circuit MCB’s and then press theGreen push button on voltage circuit.

Keep the voltage range on 300 V.Keep the voltage % switch on 100.Keep the current circuit MCB’s “OFF”

iv) Adjust the voltage by varying voltage variac to 276 V.(115% of 240 V) as per Zera Display.The minimum test period shall be 20 times the actual testperiod of starting current, the maximum test period shall belimited to 200 minutes. We normally check for 20 minutes.

v) During this test the meter shall not produce more than oneoutput pulse.vi) Test all the samples for this test.

5.4 STARTING (CL.12.14)

i) Connect the meters on the panel (testing) with current circuit ofeach phase in series with zera and potential circuit in parallel.ii) Switch “ON” the control and Zera. Also switch “ON” voltagecircuit & current circuit.iii) Adjust the voltage by varying voltage variac to 240 V. Adjustthe current as per Table 19 of IS 13779/1999 by varying currentvariac.

iv) Adjust the power factor to 1 (UPF)(For class 1 meters starting current = 0.4% Ib)For Ib=10 Amp,Starting current=0.4 X 10 = 0.040 A= 40 mA

100iii) The meter shall start and continue to register.

iv) Test all the samples for this test.

5.5 AC High voltage Test (cl.12.7.6.3)

1) Wrap the meter with aluminum foil and keep it on aaluminum bus bar which will provide earth terminal.The edgeof foil shall be within 2 cms of current carrying terminals.2)Short all the current carrying terminals together.3)Apply 2 KV AC between above shorted terminals and earthterminal ( bus bar in 1)with the help of 0-5 KV HV Test Set.

176

There should not be any flashover or breakdown.

5.6 POWER CONSUMPTION TEST (Cl.12.7.1)

Connect the meters on bench. Connect only current circuit( all meters in series ).

Set the current to Ib(basic current) and measure thevoltage drop across current coil. Product of this will give valuesin VA burden of current coils. Repeat the test for all thephases.These values should be as per Table 10 of IS.

Now connect only voltage circuit and apply 240 volts perphase keeping multi meter in series circuit. Note down thecurrent in mA. Product of this current and 240 V will giveburden value of potential coils. These values should be as perTable 9 of IS.

5.7 ENERGY REGISTRATION(Cl.12.15 of IS)

For static meters Energy registration test is carried out in activeand reactive mode.

a) ACTIVE MODEi) Connect the meters of the testing bench with current circuit inseries with load and Zera and potential circuit in parallel.

ii) Switch “ON” the Control Panel, Zera, Voltage circuit andcurrent circuitiii) Set the zera in 4 wa (4 wire active) mode and in Dial test mode.iv) Set the test point 100% voltage,Imax, UPFv) Enter 5 kwh units in Zera.vi) Note down the initial kWH reading and a rkVAh reading ofmeters under test.vii) Start the Dial test.viii) Maintain the voltage(240V per phase) and current constantthroughout the test.ix) After completion of the Dial test current circuit will beautomatically switched “OFF”.x) Note down the final readings of kWH and rKVAH units ofmeters under test.xi) There should be no change in rKVAH units as Power factor isunity.Xii) Express the error in % as X-5 X 100

5( where X = actual units passed through meter (KWh)

b) REACTIVE MODEi) & ii) Same as above.iii) Set the test in 4 Wr (4 wire reactive) mode & in Dial Testmode.iv) Set the test point 100% voltage, Imax, & 0.707 lag P.F.v) Enter 5 r KVAH units in Zera.

vi) Note down the initial & final kWh and rKVAH reading.

177

vii), viii), ix) , x) & xi) same as above.xii) Express the error in % as X-5 X 100

5(where X = actual rkVAH units passed through meter (kWh)

5.7 LIMITS OF ERRORS (CL.11.11)i) Select any 8 samples from the samples which have passed in Noload test and starting current test.ii) Connect the meters on the testing bench with current circuit inseries with Zera and load and potential circuit in parallel.iii) Switch “ON” the Control Panel, Zera, Current circuit &voltage circuit.iv) set the Zera in Accuracy test mode & 4 Wa mode. Adjust thestate of functions as AAACMH (for clamp mode & AAADMH (forDirect mode).v) Give 20 minute warm-up time on base current.vi) Adjust the scanner on the KWh pulse output LED properly.vii) Enter the meter constant & no. of pulses on Zera.Viii) Adjust the voltage = 240 V (on each phase)

Then adjust the test points (current, P.F) one by one.Test points at UPF are (balanced load on all 3Φ)5%Ib, 50%IB, 100%Ib, 200% Ib & Imax

Test points at – 0.5 lag P.F. are (balanced load on all 3 Φ)10%Ib, 50%Ib,100%Ib, 200%Ib, & I max

Allow the meters to run of each test print for at least 5-10minutes and then only start Accuracy test. No. of pulses selectedfor accuracy test should be proportionate to the meter constant &minimum 3 minute time duration may be given. Interpretation oftest results is applicable to these meters as given in clause no.12.16of IS 13779.For 3Φ meters above test points should be repeated for 1Φ load asper Table 16 of IS 13779.

5.8 INFLUENCE OF HEATING (CL.12.7.5)This test is done on only Tender sample meters.i) Connect the meters on the testing bench with current circuit inseries with Zera & load and potential circuit in parallel.ii) Switch “On” the Control Panel, Zera current circuit & voltagecircuit.iii) Set the test point V= 1.2 time rated voltage, V rep = 288V

(Per Phase) ,Current = I max ,PF= Unity.

iv) Note down the room temperature and time of starting the test.Test duration is 2 hours. Room temperature should be within 25°Cto 45°C.v) After 2 hours measure the temperature of the external surfaceof the case. Temperature rise should not be more than 20°C.vi) After the test, the meter shall show no damage and shallcomply with dielectric tests of Cl.no.12.7.6.4.of ISNote: a) Maintain current & voltage constant throughout the test.

178

c) During the test meter shall be not be exposed to draught ordirect solar radiation.

5.9 Repeatability of Error. ( as per cl. no. 11.19 of IS 13779)

i) Set the test point 100% , UPF.ii) Set the standard ref. meter on accuracy test mode.iii) Six errors tests are to be successively carried out at interval of 5minutes.iv ) The variation in meter error as expressed by the differencebetween the maximum and minimum of the errors thus obtainedshall not exceed 0.5 %.

Test pointV = 240 (Per Phase)I = 5% Ib, UPF.

Repeatability error should be calculated as per formula givenbelow:-

________________Error= / 1 ∑n ( E1- E)2

√ n-1E1=Sequence of repeated measurement at certain test point (6

different errors)E= Average value of above 6 errors.n= no. of readings such that, time required for error measurementshould be minimum 3 minutes.The error thus measured should be within the limits provided inTable 15 % of IS 13729/1999.

ix) Then change the meter mode to 4 Wr (4 Wire reactive) &check the accuracy of the meter at following test point.Voltage : 100% V reference (240 V)Test points 0.5 lag P.F (balanced load on all 3ø)

10% Ib, 50%Ib, 100% Ib, 200% Ib,Imax.These are no specified limits given in IS.

5.10 ADDITIONAL LIMITS OF ERRORS ( as pr table 16 )(Balanced 3 ø Voltage but 1ø load)

This test is carried out on only Tender Sample meters.x) Set the Zera in 4 Wa & in Accuracy test mode.xi) Adjust the balance 3phase voltage to 240 on each phase.xiii) Switch ‘ON’ only one current circuit, other two current

circuits “OFF”.

179

Test Points at UPF.5% Ib, 50% Ib, 100%Ib, 200% Ib, Imax.Test points at 0.5 lag (P.F.)

10% Ib, 50% Ib, 100% Ib, 200 Ib, Imax.xiii) All these test points are to be repeated on each phase (othertwo phases no current)xiv) The errors thus obtained should be within the limits providedin Table 16 of IS 13729/1999.

5.12 ACCURACY AND ENERGY REGISTRATION ATDIFFERENT TAMPER CONDITIONS.(as per our specification)

i) Connect the meters on the testing bench with current circuit inseries with Zera and load, and potential circuit in parallel.ii) Switch “ON” the control panel, Zera, voltage circuit & currentcircuit.iii) Set the Zera in accuracy tests mode & enter the no. of pulsesafter which error is to be checked.v) Reverse the incoming & outgoing terminals of current

circuit on R Phase. (This is one Phase reversal)

v) Set the voltage Vr n =Vyn:V yb=240V,Current = 100% Ib, UPF Set the scanner.

vi) Start the accuracy test No. of pulses selected for testing shouldbe such that, time taken for error measurement should be minimum3 minutes: Note down the error. No specified values for theseerrors.

viii) Now set the Zera in dial test mode.ix) Note down the initial kwh & rkvah readings.x) Set 5 kwh units on Zera.xi) Start the dial test.xii) Note down the final readings of kwh & rkvah units aftercompletion of the dial test.

Repeat the above procedure for two phase reversal and 3 Phasereversal.xiii) Then change the PF = 0.5 lag and repeat the accuracy test anddial test on one phase reversal, two phase reversal of three phasereversal.

For one phase failure and two phase failure procedure same buttest points are :Test point for 1 phase failureVrn= 0,Vyn =Vbn=240 (R phase Voltage circuit MCB “OFF” )Ir=0, ly=1b=100% Ib PF=UPF (R Phase Current circuit MCB‘OFF’)Test point for 2 phase failureVrn = 0, Vyn = 0, Vbn = 240 (R & Y Phase Voltage circuit MCB

180

off)Ir=0, Iy=0, Ib=100% Ib (R,Y Phase current circuit MCB ‘OFF’)PF=1 (UPF)Repeat the above tests point at 0.5 lag PF.

Neutral disconnected modeTest points arei) Vrn = Vyn=Vbn= 240 V

I r =Ib = Iy = 100% 2bPF = 1 Neutral disconnected.

measure accuracy & dial test.2) Vr n = Vyn= Vbn= 240V

1r=1y=Ib=100% Ib (but incoming & outgoing terminals ofeach phase changed, i.e. 3 phase current reversal)PF=1 Neutral disconnected.Repeat the above test points at 0.5 lag PF.


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COMPACT FLUORESCENT LAMP

1. Objective Testing of Compact Fluorescent Lamp


Integrating sphere , Suitable Kelvin Holder, Variac MECO makepower analyser


181

4. Reference BEST Specification

5. Procedure 5.1 Sampling:8 samples per lot randomly selected for testing . 6 nos. for electricalcharacteristic and 2 nos. for physical inspection.5.2 Procedure :5.2.1 Connect any one lamp from randomly selected sample in theintegrating sphere with the help of respective ‘Kelvin Holder ‘.

5.2.2 Connect the 240 V supply with MECO make Power analyserthrough variac.

5.3.2 Switch ON supply and gradually increase the voltage. Notedown the voltage at which lamp glows.

5.2.4 Increase the voltage to 240 V and note down all theparameters given below.Stating voltage

Total currentTotal wattageCircuit power factorLumen output ( Take 4 -5 readings and take the average value)All possible (i.e 3rd , 5th , 7th etc. ) voltage and current harmonicdistortion & Total harmonic distortion ( THD ).

Repeat the test for all 6 randomly selected samples.

Write down the physical observation for remaining 2 lamps.


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CEILING FAN1. Objective Testing of ceiling fan

2. Apparatus

/ material

0-5 KV HV Test Set, 500 V Megger, VAW Panel , Multi-meter,Tacho-meter, Loading Transformer, Variac

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4. Reference IS 374-1979

5. Procedure 5.1 Sampling:1) All fans supplied on DL are to be tested2) For Fan received against IM ( table 3 of IS 374 )

Lotsize

Stage Samplesize

CumulativeSamplesize

Acceptancenumbers

RejectionNumbers

Upto15

First 3 3 0 1

16 to200

First 5 5 0 2

Second 10 15 1 2201andabove

First 7 7 0 2

Second 14 21 2 3

5.2 IR Test: ( cl. No. 10.7 of IS 374 )

When tested with 500 Volt megger the resistance betweenfan circuit ( including regulator if any ) and earthing terminalshould be more than 2 M Ω.

5.3 HV Test : ( cl. No. 10.6 of IS 374 )

With the help of 0-5 KV HV Test Set 1.5 KV is appliedbetween live parts and body and maintained for one minute. Itshould not show any kind of breakdown or flashover.

5.4 Leakage current Test : ( cl. No. 10.5 of IS 374 )

Leakage current is measured between phase and earth &between nuteral and earth with mili- ammeter in circuit .Maximum value is reported. The leakage current shall notexceed 210 µ A rms.

5.5 Starting Test : ( cl. No. 10.8 of IS 374 )

The fan is connected to 85 percent of its voltage / lower limitof the voltage range , if any, with regulator at its lowest speedstep. The fan should be capable of starting. The test is repeated

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10 times.

5.6 Fan speed and input : ( cl. No. 10.9 of IS 374 )

The fan is suspended in air with the help of a hookprovided in Lab for this purpose. The fan is connected throughpower analyzer with regulator at its highest speed setting.Switch ON the fan and measure all parameters. The inputunder the above condition is measured shall not exceed themarked input by more than 10 %. Measure the speed with helpof ‘Tachometer’.* It shall not defer from the declared value by+ 10 %

5.7 Earthing Connection :

Connect the terminals of loading transformer betweenearthing terminal and each of the accessible metal part .inject 25 amps current and measure the voltage drop .Calculate the resistance by using formula R=V/I. It shouldnot be more than 0.1 Ω. Care is taken that the contactresistance between the tip of measuring probe and themetal part under test does not influence the test results.

-* A fluorescent sticker is put on outer side of fan rotor.When fan reaches constant speed while running at highest speedsetting, set the direction of tachometer beam at florescent sticker.Reading appears on meter in RPM. Take on 3-4 reading . Take themean value.


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GSM OF PAPER

1. Objective Testing of papers for GSM( grams per square meter)

2. Apparatus Electronic Weighing balance ( uptyo 100gmms.)

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4. Reference As per BEST specification

5. Procedure 5.1 Cut a square piece of 10 cm x 10 cm from samples with the10m x 10 cm square aluminum plate & a sharp blade.

5.2 Switch ‘ON’ the electronic weighing bridge & keep it in‘ON’ position for at least 20 minutes.

5.3 Calibrate the weighing balance with the help of 100 gmweight provided with weighing balance.

5.4 For calibration of the weighing machine press cal / minute &keep it press for some time cal &........... lines will appear onthe display & if will blink with 100.00. At this time putstandard 100 gm weight then after same time 000.0000 willappear on the display. Remove the 100 gm weight. Aftersome time “cal done” massage will appear on the display.

5.5 When 000.0000 will appear on display place the sample (10cm x 10 cm) at the centre in the pan of the balance.

5.6 The weight will be displayed note down this weight &multiply this weight by 100 which will give the weight ingrams per square meter.

5.7 Switch off the balance by pressing ON / OFF key and hold ittill OFF message displays.


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CHOKES FOR FLUORESCENT TUBE OF 40 WATTS1. Objective Testing of Chokes for Fluorescent Tube of 40 watts

2. Apparatus Reference Ballast, Tube light with fitting, VAW panel,5ooV megger, Resistance- meter, Thermometer

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4. Reference IS 1534 (1)/1993

5. Procedure 5.1 Sampling:

Lot Size Sample Size

N1 N2 N1+N2 C1 C2Up to 100 10 20 20 0 3101 to 200 13 26 39 0 5201 to 300 20 40 60 1 5301 to 500 25 50 75 1 6501 to 800 35 70 105 2 7801 to 1300 50 100 150 3 101301 and above 75 150 225 5 12

5.8 IR Test :

When tested between current carrying part and earthingterminal with 500 V megger each sample should show IRvalue above %MΩ.

5.9 HV Test :

With the help of 0-5 KV HV Test Set 1.5 KV is appliedbetween live parts and body and maintained for one minuteit should not show any kind of breakdown or flashover.

5.4 Operating characteristic :

5.4.1 This test is to be perfomed in illumination lab usingDELTA make VAW panel.

5.4.2 Connect the choke in VAW panel circuit with a standardtube light fitting along with respective reference ballast.

5.4.2 Switch ON the panel and record all parameters as given inthe following table. Repeat the test with all the samples.

5.5 : Temperature Rise Test :

5.5.1 This test is to performed in ‘ Heat Run Lab’ usingresistance meter, variac , am-meter, thermometer .

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There are two types of Ballasts (tw)a. Ballast without temperature marking:--

Ballast shall be tested at 110% of the rated supplyvoltage and at rated frequency.

The maximum temperature shall be 70°C Table-4b. Ballast with temperature marking Tw:-

Ballast shall be tested at rated supply voltage andat rated frequency.

The maximum temperature shall be t+25°Cwhere t=Declared temp. rise of a winding.

Temperatures are measured on windings by theresistance method, using the formula.

Max. Temp. = R2 [234.5 + Rt.] – 234.5 °C---------------------

R1Where, R1= Resistance of winding before heating.



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ELECTRONIC BALLAST

1. Objective Testing of Electronic ballast

2. Apparatus MECO make Three phase Power analyzer, Variac , Tube light

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/ material fitting complete set, 0-5 KV HV Test Set, 500V Megger


4. Reference IS - 13021

5. Procedure 5.1 Sampling: 10 samples per lot or as instructed.

5.2 IR Test : When tested with 500volts megger insulationbetween current carrying part and body shall not be less than2 MΩ.

5.3 HV Test : Tube light choke are to be tested for 1.5 KVfor 1 minute between current carrying part shortenedtogether and body/earthing.

5.4 Electronic choke generally consist of 6 wires two forpower supply and two each for both ends of tube light. Nostarter is needed. Connect the power supply to tube lightfitting through variac and power analyzer.

5.3.1 Switch on the supply and gradually increase the voltage.Note down the voltage at which tube light gets ON.

5.3.2 Clamp type CTs of size 1-10-100 is to be used as current isin mili-ampere. However while switching in it should beinitially kept on higher range and only after confirming thecurrent level select the proper current range ( mainly 1amp.).

Note down all the parameters as per the following table.

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OPERATING CHARACTERISTICS

Parameters to be checked SpecifiedValues

Test Voltage 240 VStarting time RAPID startStarting voltage -----Total Circuit Current -----Total Wattage 36 W ( max )Power Factor > 0.94Total Harmonic Distortion(THD )

20 % ( max )

Third Harmonics 28.5 % (max)Insulation Resistance ofBallast

2 M-Ohm ( min )

H.V. Test on Ballast 1.5 KV for 1min.


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