198kv lightning arresters

Specification for

220 kV Switchyard HPGC : 2 x 300 MW Deenbandhu Chhotu Ram TPP, Yamuna Nagar

DOCUMENT NO. REL-DCRTP-CEE-201-P-501 E0021 COVER

TECHNICAL SPECIFICATION NO. E0021 FOR 198KV LIGHTNING ARRESTERS

Specification for


DOCUMENT NO. REL-DCRTP-CEE-201-P-501 E0021 INDEX

SPECIFICATION FOR 198 KV LIGHTNING ARRESTERS C O N T E N T S SECTION D E S C R I P T I O N PAGE NO. 1.00.00 INTENT OF SPECIFICATION E0021:1 2.00.00 SCOPE OF WORK E0021:1 3.00.00 GENERAL REQUIREMENTS E0021:1 4.00.00 DESIGN CRITERIA E0021:2 5.00.00 SPECIFIC REQUIREMENTS E0021:3 6.00.00 T E S T S E0021:4 7.00.00 DRAWINGS, DATA & MANUALS E0021:5 ATTACHMENTS ANNEXURE-A RATINGS AND REQUIREMENTS E0021:7 ANNEXURE-B FITTINGS AND ACCESSORIES E0021:10 ANNEXURE-C MANDATORY SPARES E0021:11

Specification for


DOCUMENT NO. REL-DCRTP-CEE-201-P-501 E0021 Page 1 of 11

SPECIFICATION FOR 198 KV LIGHTNING ARRESTERS 1.00.00 INTENT OF SPECIFICATION 1.01.00 This Specification is intended to cover the design, manufacture, assembly,

testing at manufacturer's works, supply & delivery, properly packed for transport F.O.R. site of 198 KV LIGHTNING ARRESTERS complete with all materials and accessories for efficient and trouble-free operation.

1.02.00 In the event of any discrepancy with listed documents, the stipulation of this

specification shall govern. 1.03.00 This specification shall be read and construed in conjunction with other sections

of the bidding document. 2.00.00 SCOPE OF WORK 2.01.00 Scope of Supply Type and rating of the equipment listed below are further detailed in the

annexures. The ratings indicated are minimum values. Bidder shall check the same with respect to insulation coordination.

2.01.01 Each lighting arrester shall be furnished complete with accessories as listed in

the annexure. 2.01.02 All relevant drawings, data and manuals sufficient to operate, maintain & repair

main equipment and auxiliary system. 2.01.03 Commissioning spares and recommended spare parts for three (3) years

operation. 3.00.00 GENERAL REQUIREMENTS 3.01.00 Codes and Standards 3.01.01 All equipment and materials shall be designed, manufactured and tested in

accordance with the latest applicable IEC/IS except where modified and/or supplemented by this specification.

Specification for



3.01.02 Equipment and materials conforming to any other standard which ensures equal or better quality may be accepted. In such case, copies of the English version of the standard adopted shall be submitted along with the bid.

3.02.00 Annexures 3.02.01 All annexures appended to this specification shall form part of this specification

and supplement the requirements specified herein. 3.02.02 This specification shall be read and construed in conjunction with the

annexures to determine the scope of work. 4.00.00 DESIGN CRITERIA 4.01.00 The equipment will be used in 220KV switchyard of DCR TPP at

Yamunanagar. The electrical system data are as listed in the annexure. 4.02.00 The equipment will be installed outdoor in a hot, humid and tropical atmosphere

with heavy pollution. 4.03.00 All equipment, accessories and wiring shall have tropical protection, involving

special treatment of metal and insulation against fungus, insects and corrosion. 4.04.00 The maximum temperature in any part of the equipment at specified rating shall

not exceed the permissible limits as stipulated in the relevant standards. 4.05.00 The equipment shall be capable of withstanding the dynamic and thermal

stresses of listed short circuit current without any damage or deterioration. 4.06.00 There shall be no radio interference when the equipment is operated at

maximum service voltage. 4.07.00 The safety clearances of all live parts of the equipment shall be as per relevant

standards. 4.08.00 Arresters shall be designed with sufficient cantilever strength to meet with

stress due to wind pressure and short circuit forces arising from rated short time current.

4.09.00 The lightning arrester shall be installed as close to the equipment as possible

and also on the line entrance.

Specification for



5.00.00 SPECIFIC REQUIREMENTS 5.01.00 Type and Rating 5.01.01 Lightning arrester shall be station class, heavy duty, metal oxide gapless type

with ratings as detailed in the annexure. 5.01.02 The arrester shall have adequate thermal discharge capacity for severe

switching surges, long duration surges and multiple strokes. 5.02.00 Constructional Features 5.02.01 The arrester shall be single pole, hermetically sealed with non-linear blocks of

sintered metal oxide material so as to obtain a robust construction with excellent electrical, thermal and mechanical characteristics even after repeated operation.

5.02.02 Insulator shall be wet process porcelain, brown glazed and free from

imperfections. All metal parts and hardware shall be hot dip galvanised. 5.02.03 Creepage distance shall correspond to heavily polluted atmosphere. Grading

ring, if required, shall be provided to maintain voltage gradient within permissible limit.

5.02.04 The arrester shall be provided with pressure relief device to prevent shattering

of porcelain in case excessive gas pressure builds up. 5.03.00 Accessories 5.03.01 Lightning arrester shall be furnished complete with insulating base, arrester

disconnector, surge counter, leakage current monitor, insulated Cu. cable and anchoring hardware for mounting on steel structure.

5.03.02 The surge counter shall be suitably enclosed for outdoor duty and be mounted

at a convenient height for reading. Counter terminals shall be such as to permit connections with minimum possible bends. No auxiliary power supply or battery shall be required for operation of counter.

5.03.03 A leakage current detector shall be furnished with the counter as an integral

part. This is for monitoring the leakage to indicate any possible breakdown. Readings of milli-ammeter and counter shall be visible through inspection glass panel.

5.03.04 A suitably sized by-pass shunt along with necessary terminals shall be

furnished for bypassing the discharge counter if required. 5.03.05 Grading ring/corona ring as applicable for the particular voltage class of

arrester shall be provided.

Specification for



5.04.00 Terminals 5.04.01 All connection terminals shall be of corrosion resistant material and complete

connection hardware. 5.04.02 All ground terminals shall have provision of connection to G.I. flat of approved

size. 6.00.00 TESTS 6.01.00 Routine Tests 6.01.01 During manufacture and on completion, all equipment shall be subjected to the

Routine Tests as laid down in latest revision of IEC/IS. 6.02.00 Acceptance & Type Tests 6.02.01 Acceptance & type tests to be carried out on lightning arresters according to

latest revision of IEC/IS. Acceptance tests, whenever possible shall be conducted on the complete

arrestor unit. Each metal oxide block of surge arrester shall be tested for the guaranteed

specific energy capability in addition to the routine/acceptance test as per IEC/IS.

6.03.00 Special Tests 6.03.01 Special thermal stability tests to be conducted on lightning arresters according

to IEC, as an acceptance test. 6.03.02 Temperature cycle test on the porcelain housing of the arrester to be

conducted as per IS/IEC. 6.03.03 The artificial pollution test shall be carried out as per applicable standards. 6.03.04 The galvanisation test on metal parts shall be carried out as acceptance test. 6.03.05 The functional (operational) acceptance tests shall be carried out on the surge counter.

Specification for



6.04.00 Test Witness Tests shall be performed in presence of Purchaser's representative if so

desired by the Purchaser. The Contractor shall give at least thirty (30) days' advance notice of the date when the tests are to be carried out.

6.05.00 Test Certificates 6.05.01 Certified reports of all the tests carried out at the works shall be furnished in

requisite no. of copies for approval of the Purchaser. 6.05.02 The equipment shall be despatched from works only after receipt of

Purchaser's written approval of the test reports. 6.05.03 Type test certificate of any associated equipment, if so desired by the

Purchaser, shall be furnished. Otherwise, the equipment shall have to be type tested, free of charge, to prove the design.

6.05.04 The test report shall furnish complete identification of the equipment such as

serial no., rating, equipment designation and date of test. 7.00.00 DRAWINGS, DATA & MANUALS 7.01.00 Drawings, Data and Manuals shall be submitted with the bid and in quantities

and procedures as specified in General Conditions of Contract and/or elsewhere in this specification for approval and subsequent distribution after the issue of Letter of Award.

7.02.00 To be submitted with each copy of the Bid. 7.02.01 Typical general arrangement drawing showing constructional features and

disposition of various accessories. 7.02.02 Technical leaflets. 7.02.03 Type test certificate on similar equipment. 7.03.00 To be submitted for Approval and Distribution 7.03.01 Dimensioned general arrangement drawing showing disposition of various

accessories and safety clearances. 7.03.02 Transport/Shipping dimensions with weight. 7.03.03 Foundation plan and loading.

Specification for



7.03.04 Assembly drawing for erection at site with part numbers and schedule of

materials. 7.03.05 Characteristic curves for insulation coordination. 7.03.06 Any other relevant drawing or data necessary for satisfactory installation,

operation and maintenance. 7.03.07 Instruction manuals on the equipment and its various accessories. The manual shall clearly indicate method of installation, check-ups and tests to

be carried out before commissioning of the equipment.

Specification for



ANNEXURE-A RATINGS & REQUIREMENTS LIGHTNING ARRESTER 1.0 Reference Standard : IEC 99-4 / IS 3070 2.0 Type : Station class, Metal oxide gapless 3.0 Service : Outdoor, heavily polluted atmosphere. 4.0 System Details 4.1 Voltage (Nom/Max.)... KV : 220/245 4.2 Nos. of phases : 3 4.3 Frequency : 50 Hz ±5% 4.4 System Neutral : Effectively earthed 4.5 3-Phase Symmetrical Fault level : 40 KA for 1 second 4.6 Insulation level of the equipment to be protected (lightning)..KVP a) Transformer : ±950 b) CB/Isolator : ±1050 c) Instrument Transformer : ±1050 d) Across open contacts : ±1200 5.0 Arrester Duty 5.1 Type of equipment being protected : Transformer/C.B./Isolator/CT/CVT

Specification for



ANNEXURE-A 6.0 L.A. Rating 6.1 Rated Voltage : 198 KV 6.2 Nominal discharge current : 10 KA 6.3 Long duration Discharge class : Class 3 6.4 Maximum continuous operating voltage (kV rms) : 168 7.0 Insulation Level of Arrester housing 7.1 1-minute 50 Hz withstand (dry & wet) : 380 7.2 Lightning Impulse withstand : 650 8.0 Maximum Lightning Impulse Residual voltage at 8/20 µs current wave (KV peak) 8.1 At 5KA : 450 8.2 At 10 KA : 481 9.0 Switching Impulse Residual Voltage (KVP) 9.1 Maximum at 1 KAp : 409 10.0 High Current impulse withstand value (4/10 micro sec.impulse) .. KA : 100 KA 11.0 Creepage......mm (mimimum) : 6125 12.0 Mounting : Steel Structure

Specification for



ANNEXURE-A

13.0 Pressure relief current : 40KA 14.0 Pressure relief class : A 15.0 Continuous current 15.1 Resistive component of : 1000 continuous current (Max) ...microamp 15.2 Capacitive component of : 1500 continuous current (Max) ...microamp 16.0 Minimum energy handling : 4.5KJ/KV capacity

Specification for



ANNEXURE-B FITTINGS AND ACCESSORIES Each Lightning Arrester shall be furnished complete with the accessories as listed below : 1. Insulating Base with anchoring bolts, nuts etc. for fixing the equipment on to structure. 2. Surge counter with integral leakage current monitor. 3. By-pass shunt with connection provision. 4. Ground terminals. 5. Clamp type bimetallic terminal connectors to suit Twin Moose 6. Grading ring, if necessary. 7. Arrester disconnector. 8. Other standard accessories, which are not specifically mentioned but are usually

provided with Lightning Arrester of such type and rating for efficient and trouble-free operation.

Specification for



ANNEXURE-C MANDATORY SPARES Bidder shall quote for the mandatory spares indicated below. In case any item is not considered by the bidder, same shall be supplied free of cost, if found applicable during detailed engineering as per approved scheme, equipment requirement, etc

Sl. No. Description Unit Qty.

1.0 Complete surge arrester with insulating base, surge monitor and terminal connector No. 3

198kv lightning arresters

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