technical dictionary - · pdf filetechnical dictionary general data w.3 w allgemeines product...

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CertificatesW.2 - W.3

Electrical dataRating the clearance and creepage distances W.4 - W.6Current load curve W.7

General technical dataGeneral information about CE marking W.8EMV directives W.8 - W.9Protection types W.10Converting AWG conductors to mm2 W.11Gauge pin W.11

MaterialsInsulation materials W.12 - W.13Metals W.14Current loading curves W.15

Connection typesW.16 - W.17

ATEXW.18 - W.19

General data

TerminalsRegulations / definitions W.20Assembling terminal strips W.21Connecting terminals W.22Use of aluminium conductors W.23Definition of the various types W.24 - W.25Ex terminals ATEX W.26 - W.29

Relay couplersW.30 - W.31

Opto-couplersW.32 - W.34

Overvoltage protectionW.35 - W.41

ToolsCutting W.42Stripping W.43Crimping W.44

Specific data

Technical dictionary

SSB_W001-W044_GB.qxd 28.10.2003 8:56 Uhr Seite W.1

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Product certificates create trust

Certification documents verify the quality of our products. They are issued followingsuitable tests by independent institutesand are the prerequisite for use in certainmarkets or fields of application.

The accredited test laboratory has itsexpertise endorsed

The reliability of technical data is of greatimportance for the user. In confirming theaccredited status, officially approvedauthorities have certified the organisation in accordance with EN 45 001 as well asits expertise in defined assessment ofterminals, plug-in connectors, relays andelectronic equipment.

Certification as documentation ofmanaged quality

Quality management in the Weidmüllercompanies is based on ISO 9000 ff. The corresponding certificates fromacknowledged, accredited authorities alsosimplify your supplier appraisal procedures.

Verification of Weidmüller’s qualityalso includes contracts withindependent institutions covering theregular monitoring of productionfacilities, quality management and thelaboratory.

Excellent environmental managementtestifies to our total commitment.

Weidmüller quality andenvironmental managementfor the benefit of ourcustomers


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Electrical data

Rating the clearance and creepage distances of electrical equipment

General information

Since April 1997, clearance and creepagedistances have been rated according tothe regulations of DIN VDE 0110-1,“Insulation coordination for equipment inlow voltage systems”.DIN VDE 0110-1 contains the modifiedversion of the IEC report 664-1 (see IEC 664-1/10.92).The latest catalogue gives the rating dataobtained for each product in compliancewith the provisions of this standard, whereapplicable.

For the rating of clearance and creepagedistances, application of the regulationsfor insulation coordination produces thefollowing interrelationships:

Clearance distances

Clearance distances are rated inaccordance with the following factors:

• Anticipated overvoltageRated impuls voltage

• UsedOvervoltage protection precaution

• Measures to prevent soilingDegree of soiling

Diagram showing clearance distance

Creepage distance

Creepage distances are rated inaccordance with the following factors:

• IntendedRated voltage

• Used insulation materialsInsulation materials group

• Measures to prevent soilingDegree of soiling

Diagram showing creepage distance

If the corresponding clearance distance isless than 3 mm, the smallest groove widthmay be reduced to 1/3 of this clearancedistance.

Grooves are taken into account whenmeasuring creepage distances if theirminimum width X is rated according to the following table:Degree of Minimum widthsoiling X in mm

1 0.25

2 1.0

3 1.5

4 2.5


Three-phase One-phase Electrical equipment Electrical equipment Electrical equipment Specially protected systems systems with at the power supply as part of the per- for connection to the electrical equipment

mid-point of the installation manent installation perman. installation

(Overvoltage (Overvoltage (Overvoltage (Overvoltagecategory IV) category III) category II) category I)

120 to 240 4.00 2.50 1.50 0.80

230/400277/480 6.00 4.00 2.50 1.50

400/690 8.00 6.00 4.00 2.50

1000 Values for project planning in each individual case. If no values are available, the values in the preceding line apply.

*) acc. to IEC 38

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Rated impulse voltage

The rated impulse voltage is derived from:

• Voltage conductor – earth(the rated voltage of the network, takinginto account all networks)

• Overvoltage category

Stipulating the overvoltage categories

according to national standard DIN VDE 0110-1 (for electrical equipment feddirectly from the low voltage network)

Overvoltage category III

• Devices which are an integral part of the permanent installation, and otherdevices expected to have a higherdegree of availability.

e.g. distribution boards, circuitbreakers, distribution devices (includingcables, busbars, distribution boxes,switches, sockets) in the permanentinstallation and devices for industrialuse, and other devices such asstationary motors with continuousconnection to the permanentinstallation.

Overvoltage category VI

• Devices for use at or near the powersupply in the electrical installation ofbuildings, between the principaldistribution and the mains,

e.g. electricity meters, overcurrentprotection switches and centralisedcontrollers.

Overvoltage category I

• Devices for connection to the perma-nent electrical installation of a building.Outside the device, measures havebeen taken either in the permanentinstallation, or between the permanentinstallation and the device, to limit thetransient overvoltage to the relevantvalue.

Overvoltage category II

• Devices for connection to thepermanent electrical installation of abuilding,

e.g. domestic appliances, portabletools.

Electrical data


Influential factors

Rated voltage of the powersupply system *) in V

Table 1: Rated impulse voltage for electrical equipment

Rated impulse voltage in kV for

Degrees of soiling

Degree of soiling 1

• No or only dry non-conductive soiling.Soiling has no influence.

Degree of soiling 2

• Only non-conductive soiling. Temporaryconductivity must be expected occa-sionally as a result of condensation.

Degree of soiling 3

• Conductive soiling occurs, or dry non-conductive soiling which becomesconductive because of condensation.

Degree of soiling 4

• Soiling results in constant conductivity,e.g. caused by conductive dust, rain or snow.

Unless explicitly stated otherwise, thedimensioning of clearance and creepagedistances, and hence the thus-derivedrating data for electromechanical products(terminals, terminal strips, PCB connectionterminals and plug-in connectors) is basedon degree of soiling 3 and overvoltagecategory III, taking account of all networktypes.


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Insulation material group

The insulation materials are divided intofour groups depending on the comparativefigures for creepage distance (CTI:comparative tracking index):

Insulation material group

I 600 ≤ CTI

II 400 ≤ CTI < 600

III a 175 ≤ CTI < 400

III b 100 ≤ CTI < 175

The comparative tracking index is requiredto have been determined using specialsamples produced for this purpose withtest solution A in compliance with IEC 60112(DIN IEC 60112/DIN VDE 0303-1).

Rated voltage

The rated voltage is derived from the rated voltage of the power supply and the corresponding network type.


Influence factors

for insulation con- for insulation

ductor–conductor 1) conductor – earth 1)

all systems

V V V

12.5 12.5 –

24 / 25 25 –30 32 –

42 / 48 / 50**) 50 –60 63 –

30-60 63 32

100**) 100 –

110 / 120 125 –150**) 160 –

220 250 –

110-220 250 125120-240

300**) 320 –

220-440 500 250

600**) 630 –

480-960 1000 500

1000**) 1000 –

Table 3a:

Single phase 3 or 2 conductor a.c. or d.c. networks

Voltages for table 4Rated voltage

of the power

supply system

(network)*)

for insulation

conductor – earth

all systems

V V V V

60 63 32 63

110/120/127 125 80 125

150**) 160 – 160

208 200 125 200

220/230/240 250 160 250

300**) 320 – 320

380/400/415 400 250 400

440 500 250 500

480/500 500 320 500

575 630 400 630

600**) 630 – 630

660/690 630 400 630

720/830 800 500 800

960 1000 630 1000

1000**) 1000 – 1000

1) Conductor-earth insulation levels for unearthed or impedance earthedsystems are the same as those for conductor-conductor insulationbecause, in practice, the operating voltage of every conductor to earthcan match the conductor-conductor voltage. This is because the actualvoltage to earth is defined by the insulation resistance and by thecapacitive blind resistance of every conductor to earth. This means thata low (but tolerated) insulation resistance of a conductor can effectivelyearth it and raise the other two to the value of the conductor-conductorvoltage against earth.

2) For electrical equipment intended both for use in three-phase 4-con-ductor and in three-phase 3-conductor systems, both earthed andunearthed, only the values for the 3-conductor systems should be used.

*) It is presumed that the value of the rated voltage of the electricalequipment is not below the value of the rated voltage of the powersupply system.

**) Following jointly undertaken alterations, the meaning of the **) markinghas not been adopted in Table 1. Its definition: the /- dash refers to athree-phase 4-conductor system. The lower value is the voltage‘external to neutral conductor’, the higher value is the voltage ‘externalto external conductor’. If only one value is stated, it refers to three-phase3-conductor systems and refers to the voltage ‘external to externalconductor’.

Tables 3a and 3b still refer to the values in Table 1 by using the **) marking.

Table 3b:

Three-phase 4 or 3 conductor a.c. networks

Voltages for table 4Rated voltage

of the power

supply system

(network) *)

Electrical data

3-conductor systems, with mid-point earthing

for insulation conductor –conductor

three-phase 4-conductor sy-stems with eart-hed neutral 2)

three-phase 3-con-ductor systems;unearthed 1) orearthed conductor


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The derating curve shows which currentscan flow continuously and simultaneouslyacross all possible connections when thecomponent is exposed to various ambienttemperatures below its upper temperaturelimit.

The upper temperature limit of a com-ponent is a rating value which depends onthe used materials. The sum of ambienttemperature and overtemperature produ-ced by the current load (power loss at theforward resistance) must not exceed theupper temperature limit of the component,so as not to damage or destroy it. Thecurrent loading ability is therefore not aconstant value but falls with increasingcomponent ambient temperature. In addi-tion, the power loading ability is influencedby component geometry, number of pinsand connected conductor.

Current load curve (derating curve)

tg = upper temperature limit of componenttu = ambient temperature of componentln = load current

Current loading curve

tg = upper temperature limit of componenttu = ambient temperature of componentln = load currenta = basic curveb = reduced basic curve (current loading curve)

Basic curveUpper temperature limit

of the component

The current loading ability is empiricallydetermined acc. to DIN IEC 60152-3.

For this purpose, the corresponding com-ponent temperatures tb1, tb2 and the am-bient temperatures tu1, tu2 are measuredfor three different loading currents l1, l2 …

The values are entered in a linear systemof coordinates (as shown in Fig. 1) toillustrate the relationships between theloading currents, the component ambienttemperature and the component over-temperature.

The Y-axis is used for the loadingcurrents and the X-axis for the ambienttemperatures. A perpendicular on the X-axis at the component's upper temper-ature limit tg completes the coordinatesystem

For every current l1, l2, .. the correspond-ing mean values for component overtem-peratures ∆ t1 = tb1 – tU1, ∆ t2 = tb2 – tU2,are entered starting from the perpendic-ular and working to the left. The points found in this way are connect-ed to form a parabolic curve.

In view of the fact that it is effectively notpossible to select components with maxi-mum permissible forward resistances formeasurement purposes, the basic curvehas to be reduced. A reduction of theloading currents to 80% results in the “power loading curve”. Here allowancehas to be made for the maximum tolerableforward resistances and inaccuracies incurred in measuring the temperatures,so that these curves are adequate forpractical use as indicated by experience.If, within the low ambient temperature range, the current loading curve exceedsthe current permissible as based on thecurrent loading ability of the conductorcross-sections requiring connection, thenthe current loading curve is limited to thesmaller current for this temperature range.

Electrical data


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General technical data

General information about CE marking

EMC directives

The CE mark on various products andtheir packaging is neither a quality featurenor an indication of quality or safety. The CE mark is a control sign that wascreated and brought into effect for opentrading within the European market.It does not refer to the address of the endconsumer. The CE mark only confirmsthat a manufacturer has complied with allof the directives of the European Union(EU) that are applicable to this product.Therefore the CE mark is proof of directive conformity and is directedtowards the responsible control authorities. The CE mark can be said to be the passport for products that are to be traded within Europe.

Weidmüller considers all relevant EUdirectives to the best of its knowledge.The currently applicable directives are as follows:

73/23/EEC

Electrical equipment for use within specific voltage ranges (Low voltagedirective)

89/336/EEC

Electromagnetic compatiblity (EMC directive)

98/392/EEC

Safety of machines (Machinery directive)

The standards mentioned in the directiveshave been an element of Weidmüller'sstandard development for a considerabletime. This provides the guarantee of conformity to the European directives. Our testing laboratory, accredited according to EN 45001, performs thestandard conform testing. The testingreports are recognised within Europe within the framework of the accreditationprocess.

73/23 EECLow-Voltage Directive (LVG)

Electrical equipment in the sense of this directive are all electrical equipments that are used with a nominal voltage between 50 and 1000 Vac and between 75 and 1500 Vdc.

If an electrical product has the CE mark, it must fulfil the requirements of the EMC directive and if necessary the low-voltage directive (above 50 Vac and above 75 Vdc).

According to the low-voltage directive, aconformity evaluation process must be per-formed on the product whereby conformity to the directive is assumed wherea reference to the harmonised Europeanstandards or to the other technical specifica-tions, e.g. IEC standards or national stan-dards, is made.

With the decree of the Directive of the council dated 3rd. May 1989 for the alignment of the legal requirements of themember states concerning electromagneticcompatibility (89/336/EEC), the EuropeanUnion (EU) has declared EMC as a protection objective.

The protection objectives are defined in article 4 of the EMC directive dated 19th.November 1992, and state the following:

– the generation of electromagnetic interference must be so reduced so thatthe intended operation of radio, telecommunications and other devices ispossible.

– the devices must have a suitable resistance to electromagnetic interferencein order to ensure intended operation.

Devices are defined in the EMC directive as:

– all electrical and electronic equipment,installations and systems that containelectrical and electronic components

This applies to active/passive componentsand intelligent modules that are producedand stored by Weidmüller.

The adherence to this directive is assumedfor the devices that conform with the harmonised European standards that, forexample, are released in the gazette fromthe Federal Minister for Post and Tele-communications.

The devices are utilised in the followingareas:

– industrial installations

– medical and scientific equipment anddevices

– information technology devices

Weidmüller tests its electronic products according to the relevant standards in orderto fulfil the agreed protection objectives.

Electronic Products from WeidmüllerRegarding EMC Guidelines

Category 1

All passive components such as:

– terminals with status displays

– protection terminals with status displays

– passive interface elements with andwithout status displays

– overvoltage protection

These products cause no interference andthey have a suitable immunity to interfer-ence. These products are not labelled withthe CE mark concerning the EMC directiveor the EMC guideline.

Category 2

These products are labelled with the CEmark after the conformity evaluation process has been performed which contains the reference to the harmonisedEuropean standards.

The following are harmonised standards:

EN 50081-1Generic Emission Standard for residential, commercial and light industrialenvironments

EN 50082-1Generic Immunity Standard for residential, commercial and light industrialenvironments companies

EN 50081-2Generic Emission Standard for heavyindustrial environments

EN 50082-2Generic Immunity Standard for heavyindustrial environments

EN 55011Radio Interference for ISM Devices

EN 55022Radio Interference for InformationTechnology Facilities

EN 61000-3-2Harmonics

EN 61000-3-3Voltage Fluctuations

EN 6100 0-4-xapprox. 10 partial tests for interferenceimmunity; partly not ratified.


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EMC directives

Criterion B

The equipment shall continue to operateas intended after the test. No degradationof performance or loss of function is allowed below a minimum performancelevel as specified by the manufacturer,when the equipment is used as intended.

In certain cases, the minimal performancelevel can be replaced by an permissibleloss of performance. During testing degradation of the performance level ispermitted however changes to the specified operation mode or data loss arenot permitted.

If the minimal performance level or permissible loss of performance is notspecified by the manufacturer, both ofthese specifications can be extracted fromthe description of the product, the relevantdocumentation and from what the opera-tor expects from the equipment during itsintended operation.

Criterion C

A temporary loss of function is permitted,provided the loss of function is self recoverable or can be restored by theoperation of the controls.

Criterion B is most frequently specified inthe generic standards and is used by Weidmüller.

An example of an analogue coupler EMA:

During testing, the analogue coupler canconvert values that are outside the permissible tolerances.After testing however, the values must bewithin the available tolerances.

General Installation Instructions

In agreement with the performance leveland the criteria A and B, the products areallowed and can be affected externallyduring the occurrence of a fault.

It should be attempted, as far as possible,to prevent this with an optimal installation.

Measures:

– installation of the products in an enclosed metal box (control cabinet,metal housing)

– protect the voltage supply with an overvoltage protection device. (For mains supply of 230/400 Vac with a PU type and for 24 Vdc with an EGUor LPU.)

– only use shielded cables for analoguedata signals

– follow ESD measures during installation,maintenance and operation

– distance between electronic modulesand interference sources (e.g. invertors)and power lines should be at least 200 mm.

– maintenance of ambient temperatureand relative humidity

– long cables are to be protected by over-voltage protection devices.

For safety reasons, the operation of walkie-talkies and mobile telephonesshould only be performed outside a radius of 2 m.

Usage of Tests

Generic standards are always used when device-specific product standardsdo not exist. The generic standards of EN 50081-2 and EN 50082-2 are usedas the basis for Weidmüller products.

Remark:The relevance of EN 50082-1 for certainproducts must be checked as well as howfar EN 50081-1 or 50082-1 was consid-ered during testing. The environment phenomenon and testinterference levels are specified in thegeneric immunity standard. Additionally,Weidmüller considers the evaluation criteria A, B and C.Text extract from the Generic Standard EN 50082-2:

Criterion A

The equipment shall continue to operateas intended. No degradation of performance or loss of function is allowedbelow a minimum performance level asspecified by the manufacturer, when theequipment is used as intended.

In certain cases, the nominal performancelevel can be replaced by an permissibleloss of performance.

If the minimal performance level or permissible loss of performance is notspecified by the manufacturer, both ofthese specifications can be extracted fromthe description of the product, the relevantdocumentation and from what the opera-tor expects from the equipment during itsintended operation.


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Protection rating according to EN 60 529 / DIN 0470

The protection ratings are indicated by a code consisting of the two invariable letters IP and two digits representing the degree of protection.

Example: I P 6 5

2nd digit: protection from water

1st digit: protection from solid bodies

Degrees of protection from water (2nd digit)

Not protected

Vertically falling drops must not have any harmful effect.

Vertically falling drops must not have any harmful effect if the housing is inclined at an angle of up to 15° to the vertical on both sides.

Water sprayed at an angle of up to 60° to the vertical on both sides must not have a harmful effect.

Water splashing against the housing from anydirection must not have a harmful effect.

Water sprayed against the housing from anydirection must not have a harmful effect.

Water aimed in a strong jet against the housingfrom any direction must not have a harmful effect.

Water must not penetrate in any quantity whichcauses harmful effects if the housing is temporarilysubmerged in water under standard pressure andtime conditions.

Water must not penetrate in any quantity whichcauses harmful effects if the housing is permanentlysubmerged in water under conditions which mustbe agreed between manufacturer and user. However, the conditions must be more adversethan under number 7.

Degrees of protection from solid foreignbodies (1st digit)

Not protected

Protected from solid foreign bodies 50 mm in dia-meter and above. Protection to prevent dangerousparts being touched with the back of the hand.

Protected from solid foreign bodies 12.5 mm in dia-meter and above. Protection to prevent dangerousparts being touched with the fingers (finger-safe).

Protected from solid bodies 2.5 mm in diameterand above. Protection to prevent dangerous partsbeing touched with a tool.

Protected from solid bodies 1 mm in diameter andlarger. Protection to prevent dangerous parts beingtouched with a piece of wire.

Dust protected. Penetration of dust is not com-pletely prevented, but dust must not penetrate inquantities that would impair satisfactory working of the device or safety.

Dust-proof, no penetration by dust.

Number

0

1

2

3

4

5

6

Number

0

1

2

3

4

5

6

7

8



AWG mm2

28 0.0826 0.1324 0.2122 0.2220 0.5219 0.6518 0.8217 1.0416 1.3115 1.6514 2.0813 2.6312 3.3111 4.1710 5.269 6.638 8.377 10.556 13.305 16.774 21.153 26.672 33.631 42.410 53.48

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Converting AWG conductors to mm2

Rigid conductor(single- or multi-core) mm2

1.5

2.5

4

6

10

16

25

35

50

70

95

120

150

Designation

A 1

A 2

A 3

A 4

A 5

A 6

A 7

A 8

A 9

A 10

A 11

A 12

A 13

Diameter

a

mm

2.4

2.8

2.8

3.6

4.3

5.4

7.1

8.3

10.2

12.3

14.2

16.2

18.2

Width

b

mm

1.5

2.0

2.4

3.1

4.0

5.1

6.3

7.8

9.2

11.0

13.1

15.1

17.0

Designation

B 1

B 2

B 3

B 4

B 5

B 6

B 7

B 8

B 9

B 10

B 11

B 12

B 13

Diameter

a

mm

1.9

2.4

2.7

3.5

4.4

5.3

6.9

8.2

10.0

12.0

14.0

16.0

18.0

Tolerabledeviations for aand b mm

0 – 0.05

0 – 0.06

0 – 0.07

0 – 0.08

Conductor cross-sectional area

Pin

Form A Form B

Gauge pin acc. to IEC 60947-1 section 8.2.4.5.2 table 7

Possibility of inserting unpreparedround conductors with the largeststipulated cross-sectional area

Testing with stipulated gauge, insertedunder own weight.

AWG is the abbreviation for “AmericanWire Gauge”. This gives no indication ofthe actual conductor cross-sectional area.

The relationship between AWG and mm2

is shown in the following table.



PlasticAbbreviation

Colour

Description

PropertiesSpecific forward resistance acc. to IEC 93

Dielectric strength acc. to IEC 243-1

Creepage current resistance (A) to IEC112

Upper max. tol. limit temperature

Lower max. tol. limit temperature, static

Combustibility acc. to UL 94

Fire behaviour acc. to railways standard

Thermosetting plastics

GerminKrG

Melamine resin pressing compound

MF type 150(DIN EN ISO 14 528)

Organic filler

mid-yellow

1011

10

≥ 600

130

– 60

V-0 (5 V-A)

StaminKrS

Melamine resin pressingcompound

MF type 156(DIN EN ISO 14 528)

Inorganic filler

anthracite

108

12.5

≥ 600

140

– 60

V-0 (5 V-A)

Epoxy resinEP

Epoxy resin with

inorganic filler

black

1014

160

≥ 600

160

– 60

V-0

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Materials

Insulation materials

In order to satisfy all the different requirementsmade of our products, we have to use variousinsulation materials tailor-made to each specificapplication.

All insulation materials used by Weidmüller are freefrom harmful substances. It is especially importantthat these materials contain no cadmium. Inaddition, they are free from heavy metal colourpigments, dioxin and furan-forming substances.

Thermosetting plastics have outstanding dimensional stability, low water absorption, excellentcreepage current resistance and outstanding fire resistance.

Their continuous service temperature is higher than that of thermoplastics. Under high thermalload, thermosetting plastics have better dimensional strength than thermoplastics.

Thermosetting plastics are, however, inferior to thermoplastics in terms of their flexibility.

high continuous service temperature

high fire resistance

high creepage current resistance

inherent flammability protection

continuous service temperature higher

(than Germin)

high fire resistance

high creepage current resistance

inherent flammability protection

very good electrical properties

very high continuous servicetemperature

resistant to high-energy radiation

halogen- and phosphorous-free; flame retardant


Wemid

Wemid is a modifiedthermoplastic whoseproperties are especiallytailored to make it suitable foruse in our power connectors.Advantages over PA includeenhanced fire protection andhigher continuous servicetemperature. Wemid fulfils thestrict requirements for use inrailway vehicles according toNF F 16-101.

special Weidmüller insulating material

dark beige

1012

25

600

120

– 50

V-0

I2 / F2 *)

*) also qualified acc. to LUL E 1042

PolyamidePA

Polyamide (PA) is one of the most frequently usedtechnical plastics. Theadvantages of this materialincludes its very goodelectrical and mechanicalproperties, flexibility andresistance to breakage. In addition, its chemicalstructure gives PA good fireresistance even without theuse of flame retardants.

insulating material

beige

1012

30

600

100

– 50

V-2

Polyamide PG GF

Glass-fibre reinforcedpolyamide (PG GF) offers excellent dimensionalstability and very goodmechanical properties.This makes it ideal for use asend bracket.Unlike PA, this material inunreinforced state comesunder combustibility class HBin accordance with UL 94.

insulating material

dark beige

1012

30

500

120

– 50

HB

Polybutylene terephthalate PBT

Thermoplastic polyester(PBT) offers excellent dimensionalstability (which is why it isused for plug-in connectors)and high continuous servicetemperature. It has lowercreepage current resistancethan other insulationmaterials.

with or without glass-fibre reinforcement,

depending on use

orange

1013

28

200

115 / 130

– 50

V-0

PolycarbonatePC

with or without glass-fibre reinforcement,

depending on use

grey

1016

≥ 30

≥ 175

115 / 125

– 50

V-2 / V-0

I2 / F2

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Thermoplastics

Materials

higher continuous service temperature

enhanced fire resistance

halogen- and phosphorous-free; flame retardant

low smoke

permitted for use in railwaysacc. to NF F 16-101

flexible, resistant to breakage

good electrical and mechanical properties

self-extinguishing properties

excellent dimensional stability

very good mechanical properties

high dimensional stability

good electrical and mechanical properties

flame retardant, without dioxin and furan-forming

substances

high dimensional stability

high continuous service temperature

high electrical insulating power

halogen-free; flame retardant


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Metals

Weidmüller uses only tried and testedmaterials for the electrical components inits products.

All materials are subjected to rigorousquality monitoring under a qualitymanagement system certified to DIN EN ISO 9001.

Environmental compatibility plays a crucialrole in the selection of materials.

All metals used by Weidmüller areselected, processed and surface-treatedaccording to the very latest technicalfindings.

Steels

Steel parts whose function is topermanently maintain contact force arezinc electroplated, with an additionalchromate layer added to provideadditional passivation.

Surface protection complies with the veryhighest standards. Results from laboratorytests are incorporated in producing thesurface finish.

Zinc still offers corrosion protection over alonger period of time even if the zinccoating is partially damaged by scratchesor pores.

Zinc acquires a negative charge in relationto steel under the influence of anelectrolytic fluid. The metal ions in the zincmigrate to the steel giving the basematerial lasting protection againstcorrosive attack.

Conductive materials

The current-carrying materials copper,brass and bronze are characterised byboth high conductivity and goodmechanical properties.

The surfaces are usually finished with tinplating. This guarantees that the contacthas outstanding “adaptive” properties withlow transition resistance. The tin platingnot only gives consistently good electricalproperties but also affords excellentprotection from corrosion.

Soldered connections are also providedwith tin plating. To safeguard solderingability over longer periods of time (storageperiods), brass parts are also given anadditional nickel layer to serve as adiffusion barrier.

The nickel layer is highly effective inpreventing zinc atoms from diffusing out of the brass.

Materials


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The maximum current which a terminalcan carry depends on:

• the inherent temperature rise of theterminal

• the ambient temperature

• the cross-sectional area of theconnected conductor

An upper service temperature has beendefined for every Weidmüller terminal, andthis must not be exceeded in continuousoperation.

The continuous service temperaturedepends on the insulation material used inthe terminal. According to EN 60 947-7-1,a terminal may not heat up by more than45 K.

When the input current is at leastequivalent to the rated current, themaximum ambient temperature to which a terminal may be subjected is equal tothe continuous service temperature for the insulation material used, less themaximum tolerable temperature rise of the terminal acc. to EN 60 947-7-1.

Figs. 1–3 show examples of currentheating curves (in this case for a ratedcurrent of 32 A) for three differentinsulating materials:

• Thermoplastic (polyamide 66)

• WEMID

• Duroplastic (MF 150 KrG)

Depending on the insulation materialused, the rating current can be conductedup to an ambient temperature of 55 °C forPA 66, 75 °C for Weidmüller’s insulationmaterial WEMID, or up to 85 °C forduroplastic insulation materials (KrG).

Above these temperature limits, thecurrent is to be reduced in accordancewith the current expectancy curves.

0 10 20 30 40 50 60 70 80 90 100 110 120 130 140

35

30

25

20

15

10

5

0

Ambient temperature T [°C]

Load

ing

curr

ent [

A]

0 10 20 30 40 50 60 70 80 90 100 110 120 130 140

35

30

25

20

15

10

5

0


for upper continuous service temperature 120°C – Wemid


Load

ing

curr

ent [

A]

0 10 20 30 40 50 60 70 80 90 100 110 120 130 140

35

30

25

20

15

10

5

0


for upper continuous service temperature 130°C – MF 150 KrG


Load

ing

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ent [

A]


for upper continuous service temperature 100°C – polyamide 66

Current loading curves

Materials


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Weidmüller’s tension clamp systemoptically combines the specific propertiesof steel and copper. The system hasproven its worth billions of times over invarious Weidmüller products. Both thetension clamp and the clamping screwconsist of hardened steel. This clampingyoke unit generates the necessary contactforce. Connection of the conductorinvolves the tension clamp pressing theconductor against the busbar, which ismade of copper or high-quality brass. Weidmüller’s tensionclamp produces a gas-tight, vibration-resistant connection between the con-ductor and the busbar.

Vibration resistanceThe force generated by turning theclamping screw means that the upperthread overlap springs back and exerts a counter-effect on the screw.

Weidmüller’s tension clamp system isvibration-resistant.

Any settling of the connected conductor is counteracted by the elastic behaviour ofWeidmüller’s tension clamp. This means itis not necessary to “tighten” the clampingscrew.

Clamping yoke connection

With its patented pressure clamp con-nection, Weidmüller has developed ascrew connection system for conductorswith large cross-sectional areas. Thescrew unit can be taken right out of theterminal, making it easier to insert largerconductors (which often otherwise provesdifficult). The conductor is placed directlyon the busbar, the screw unit replacedand the conductor clamped in position.

Pressure clamp connection

Vibration resistanceThe difference in length “d” between theshank of the clamping screw and theresilient pressure clamp means that thepressure clamp undergoes elasticdeformation when the screw is tightened.The high spring force of the pressureclamp gives rise to vibration resistanceand at the same time counteracts thetendency for the connected conductor tosettle. It is not, therefore, necessary to“tighten” the clamping screw.

Weidmüller’s TOP connection systemfulfils the requirement that conductorinsertion and screw actuation take placein parallel. This brings wiring advantagesin certain installation situations, forexample with close lateral spacing ininstallation boxes. The TOP connectionsystem combines the special properties ofsteel and copper. The hardened steelpressure clamp presses the conductordirectly against the copper or brassbusbar. The high contact force guaranteesa gas-tight connection betweenconductor and busbar.

Vibration resistanceThe force exerted by the steel pressureclamp when the screw is tightened pullsthe two halves of the TOP connectionthread apart, as in the tension clamp. This exerts a braking effect on the screwand guarantees outstanding vibrationresistance.

TOP connection

Connection types


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Tension clamp connection IDC technology Direct push in technology

Weidmüller’s tension clamp systemfunctions in similar fashion to the tried andtested clamping yoke. As with the latter,the tension clamp preserves theseparation of mechanical and electricalfunctions. The tension clamp of high-quality rust- and acid-resistant steel pullsthe conductor against the galvanisedcopper busbar. The surface-treatedbusbar has low contact resistance and ishighly resistant to corrosion. Theseproperties are preserved by the balancingeffect of the tension clamp.

IDC (insulation displacementconnection) technology is a means ofconnecting copper conductors whichinvolves absolutely no preparation of theconductor – in other words, no strippingand no crimping.

When the conductor is connected, itsinsulation is penetrated and, at the sametime, the electrical contact is producedbetween the conductor and the busbar.

As with the other types of connection,Weidmüller’s IDC principle ensuresseparation of mechanical and electricalfunctions.

A stainless steel spring presses the busbaragainst the conductor, thus guaranteeinglow contact resistance and a gas-tight,vibration-resistant connection.

Direct push in technology involves thestripped solid conductor simply beingpushed into the terminal as far as it will go– that’s all there is to it. No tools arerequired, and a reliable, vibration-resistantand gas-tight connection is produced.Even flexible conductors with crimped wireend ferrules or ultrasonic weldedconductors can be connected without anyproblems.

A stainless steel spring, held in a separatecage, guarantees that the conductorexerts a strong contact force on thebusbar (copper- and tin coated). Theconductor pull-out forces are even higherhere than in the tension spring system.

In the steel cage, a spring and aconductor stopper guarantee optimumconditions for connection and guide thescrewdriver for the purpose of releasingthe conductor.

Connection types


Explosion groups

Gas (e.g.) CENELEX NEC 500

Propane IIA DEthylene IIB CHydrogen IIC BAcetylene IIC AMethane (mining) I Mining (MSHA)

Classification for explosion-risk areas

CENELEC Presence of a potentially Device US Classifi- Flammableclassification explosive atmosphere category cation NEC500 mediaIEC60079-10

Zone 0 constant, long-term 1G Class I, Div 1 Gases, vapoursZone 20 or frequent 1D Class II, Div 1 DustZone 1 occasional 2G Class I, Div 1 Gases, vapoursZone 20 2D Class II, Div 1 DustZone 2 rare and 3G Class I, Div 2 Gases, vapoursZone 22 short-term 3D Class II, Div 2 Dust

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Protection class

Protection Code CENELEC IEC Device categoryEN explosion-protected

Gen. requirements – 50014 60079-0 –Oil encapsulation o 50015 60079-6 2Overpressure encapsulation p 50016 60079-2 2Sand encapsulation q 50017 60079-5 2Pressure-resistant encapsulation d 50018 60079-1 2Increased safety e 50019 60079-7 2Inherent safety ia 50020 60079-11 1Inherent safety ib 50020 60079-11 2Type n (EEx n) n 50021 60079-15 3Sealing encapsulation m 50028 60079-18 2

ATEX 95 (formerly ATEX 100a)

The former directive for Ex protectionissued by the European Council under 76/117 EEC became invalid with effectfrom 1 July 2003. Now only directive94/9/EEC or ATEX 95 applies (ATEX:Atmosphère Explosive); this is one of theso-called “new approach” directives. It applies in all countries of the EuropeanUnion together with Iceland, Liechtensteinand Norway. In these countries it refers to the sale andcommissioning of products which havebeen specially developed for areas inwhich the presence of gases, vapours, fogor dust give rise to a potentially explosiveatmosphere. It now also covers the miningindustry and purely mechanical devices.

The ATEX directive has been in force sinceMarch 1996. It was valid on an optionalbasis through to 30 June 2003 (interimperiod) in parallel to the existing directives.As of this date, all new systems and devi-ces for installation in explosion-risk areasmust conform with the ATEX directive andbe certified accordingly. The former cate-gorisation into zones (zone 0, 1 or 2) andprotection classes (e.g. “i”: inherent safety,“e” enhanced safety) still apply.

Temperature classes

Max. surface Temperature class Temperature classtemperature (°C) CENELEC NEC 500-3

450 T1 T1300 T2 T2280 – T2A260 – T2B230 – T2C215 – T2D200 T3 T3180 – T3A165 – T3B160 – T3C135 T4 T4120 – T4A100 T5 T585 T6 T6

ATEX


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ATEX 95 (formerly ATEX 100a)

Marking exampleTerminal WDK 4 N V

Rated voltage

CENELEX protection class“e” – enhanced safety

Device group IIabove ground (gases, vapours,fog, dust)

Rated conductor cross-sectional area

Device group II - above ground (gases, vapours, fog, dust)

Device category 2 – use in zone 1 or 21

Approved for use in gases “G” and/or dust “D”

European symbol forexplosion protection

Approval number

Example of markingAssembled enclosurefor enhanced safety

Device category 2Use in zone 1

Approved for usein gases “G”

CENELEC ignition protection“e” – enhanced safety

Device group II – above ground(gases, vapours, fog, dust)

Temperature class T6

Approval number

Rated voltage

Rated conductorcross-sectional area

Device category 2use in zone 21

Approved for usein dust “D”

Max. surface temperature withoutdust ignition 100°C

Enclosure protection > IP64

ATEX


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Terminals

Terminals acc. to VDE 0611-1

This standard was published in Germanyin August 1992:

VDE 0611-1 Low-voltage switchgear part 7: Ancillary equipment section 1 –Terminal blocks for copper conductors.

The contents of this standard correspondto the international standard:

IEC 60947-7-1:

1989 Low voltage switchgear and controlgear part 7: Ancillary equipment section 1– Terminal blocks for copper conductors

At the European level this standard hasbeen ratified by CENELEC, making it validin the following countries:

Austria, Belgium, Denmark, Finland, France, Germany, Greece, Holland, Ice-land, Ireland, Italy, Luxembourg, Norway,Portugal, Spain, Sweden, Switzerland,United Kingdom

Combined application in order of priority:IEC 60947-1Low-voltage switchgear and control gearpart 1: General RulesEN 60947-1VDE 0660 part 100Low-voltage switchgear part 1: General Rule

Scope VDE 0611-1

(EN 60947-7-1)(IEC 60947-7-1)

This standard stipulates the requirementsfor terminals with screwed or screwlessterminal strips intended primarily for indus-trial or similar use, with the terminalsfastened to a carrier to produce both elec-trical and mechanical connectionsbetween copper conductors. It applies to terminals used for connecting roundcopper conductors with a cross-sectionbetween 0.2 mm2 and 300 mm2 (AWG24/600 kcmil), and for electronic circuitsup to 1000 Vac 1000 Hz or up to 1500Vdc.

Remarks:This standard is also used as guide forspecial kinds of terminals (e.g. isolatingterminals) for which no special standardsare available.

Terminals/feed-through terminals

An insulating part which carries one orseveral mutually insulated terminal arraysintended for fastening to a carrier.

Rated cross-section

The rated cross-section of a terminal isthe cross-section of the conductor to beconnected by the terminal as stated bythe manufacturer. It is determined by cer-tain thermal, mechanical and electricalrequirements, and is one of the specifi-cations marked on the terminal.

The rated cross-section is selected fromthe following standard cross-sections:

0.2 – 0.5 – 0.75 – 1 – 1.5 – 2.5 – 4 – 6 –10 – 16 – 25 – 35 – 50 – 70 – 95 – 120 –150 – 240 – 300 mm2.

The terminals have a rated connectioncapability, which is at least two stagessmaller than the rated cross-section. Theconductors may be solid, stranded orflexible and, if necessary, may have theirends pre-treated. The rated cross-sectionis verified using the gauges stipulated byVDE 0660 part 100 table 7 (see pageW.14).

Rated currentEach rated cross-section is assigned aparticular test current stipulated by VDE 0611-1. At these rated currents, ter-minals are not subject to non-permissibleincreases in temperature.

mm2 1.5 2.5 4.0 6.0 A 17.5 24 32 41

mm2 10 16 25 35A 57 76 101 125

mm2 50 70 95 120A 150 192 232 269

mm2 150 185 240 300A 309 353 415 520

Rated voltageVDE 0611-1 / VDE 0660 part 100

The rated voltage of a terminal is the ratedinsulation voltage to which the insulationtests and creepage distances refer. It isdefined analogously to DIN VDE 0110-1,and is one of the specifications marked on the terminal.

Rated surge voltage DIN VDE 0110-1 / VDE 0660 part 100

Peak values of a surge voltage which canbe applied to the terminals and to whichthe clearance distances acc. to VDE 0660part 100 or DIN VDE 0110-1 refer.

Degree of soilingDIN VDE 0110-1 / VDE 0660 part 100

The degree of soiling stipulates the influ-ence of solid, liquid or gaseous foreignparticles, which may reduce the dielectricstrength or specific surface resistance(see also page W.5).

Terminals for use in the industrial field ofapplication are assigned degree of soiling3: either conductive contamination mayoccur or, alternatively, dry, non-conductivecontamination which becomes conductivein the likely event of condensation.

The minimum clearance distance is stipu-lated in combination with the rated surgevoltage in VDE 0660 part 100 or DIN VDE 0110-1.

Operating conditions

Terminals can be operated under thefollowing normal conditions:

• Ambient temperature – 5 °C … +40 °C,mean temperature 24 h + 35 °C

• Altitude up to 2000 m a.s.l.

• Relative humidity 50% at + 40 °C, 90%at 20 °C.

CE mark

A EU directive stipulates that labelling withthe CE mark is carried out by the manu-facturer. The mark indicates to the stateauthorities that the item complies with therelevant directives. It thus guarantees freetrade within Europe.

Conductor connectors from ≥ 50 V ~ / 75 V- comply with the basic safety requi-rements stated in the low-voltage directive73/23/EEC (amended by 93/68/EEC).

CE marking acc. to the marking directive93/68/EEC has been mandatory since 1 January 1997.

It is affixed to the packaging.

Declarations of conformity are kept avail-able for inspection by the relevant nationalsupervisory agencies as part of the tech-nical documentation.

CE markRegulations / definitions


Working on electrical connectionelements with non-insulatedscrewdrivers

Work using non-insulated screwdriversmay only be carried out in disconnectedsystems.

The following five safety rules must beobserved when disconnecting a systembefore beginning work and in order toensure the system remains disconnectedat the working site for the duration of thiswork:

• Disconnect

• Secure to prevent the system frombeing switched on again

• Ascertain that the system is not live

• Earth and short circuit the system

• Cover or cordon off anyneighbouring live parts

These five rules constitute the safetyprecautions for working with electricalsystems and equipment. The measures to be taken in accordance with operatingand local conditions, e.g. for high- andlow-voltage overhead lines, cables orswitchgear, are stipulated in detail in VDE 0105 part 100.

Live terminals which are not in use

Any terminals which are not in use andwhich could carry live voltage are to befitted with suitable covers (e.g. ADP 1...4)to prevent them from being inadvertentlytouched. The clamping screws of ter-minals, which are not in use, even thosethat are not live, are to be screwed tight.

VDE 0105 part 100Operation of electrical installations:Work

Troubleshooting with two-pole voltagedetectors including voltage tester acc. toIEC 61243-3.

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Terminals

Mounting and end brackets

• Terminal strips mounted from left to right

• Closed side on the left, open side onthe right

• Open side of the terminal always closedusing end plates or partition plates(WAP/TW; ZAP/TW and IAP)

• End brackets placed at the beginningand end of the terminal strip

• End bracket not required next to PEterminals. Exceptions: WDK/PE andZPE

Combinations of different terminals

• End plates or partition plates (WAP/TW,ZAP/TW and IAP) must be used whenthe contour changes.

• For adjacent terminals with differingrated voltages, end plates or partitionplates (WAP/TW, ZAP/TW and IAP)must be used in order that therespective rated voltages are adheredto.

• When the PE terminal is positioned nextto or between corresponding feed-through terminals of the same seriesand size, this does not influence therated voltage or rated surge voltage ofthe feed-through terminals.

Dimensions

The overall dimensions of the terminalswith fastening parts are stipulated, butwithout tolerances. A mounting toleranceof 0.2 mm must be added to the terminalwidth when planning projects.

Partition plate

The partition plate is necessary for visualseparation of circuits or for electricalseparation of neighbouring cross-connections.

Partition disc

Partition discs can be retrofitted betweencross connectors or sockets in terminalsup to a max. terminal width of 12 mm.

Compliance with the rated insulationvoltage

The required stripping length for everyWeidmüller product is stated in mm.These lengths, such as < 6 mm ± 0.5mm, > 10 mm ± 1 mm, must be adheredto. This also applies when using ferrules.

The external dimensions of crimpedferrules must comply with IE 60947-1(1999 version).

Assembling terminal strips

Terminals


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Connecting terminals

Torque ranges for clamping screws

Tightening the clamping screws in thistorque range guarantees:

• secure, gas-proof clamping

• no mechanical destruction of thetension clamp

• voltage drop far below the required limit

The test torque acc. to IEC 60947-1(supplemented by Annex C1 of IEC 60947-1-7 or the torque stated by the manufacturer) is the lower value of thetorque range, at which all tests aresuccessfully passed.

The upper value of the torque range is themaximum torque to be applied by theuser.

The electric screwdriver should preferablybe set to the middle torque of theclamping torque range.

The table gives the generally applicablevalues. Product-specific data are listedelsewhere for the respective products.

Products with head screw with slotted head

Thread Torque range

Steel screws

min. 8.8 A 2/A 4-80

[Nm] [Nm]

M 2.5 0.4…0.8 0.4…0.8

M 3 0.5…1.0 0.5…1.0

M 3.5 0.8…1.6 0.8…1.6

M 4 1.2…2.4 …

M 5 2.0…4.0 …

M 6 2.5…5.0 …

Products with head screw with slotted head

Thread Torque range

NE screws

Cu 2 (CuZn) Cu 5 (CuNi 60)

[Nm] [Nm]

M 2.5 0.4…0.45 …

M 3 0.5…0.6 0.5…1.0

M 3.5 … 0.8…1.6

M 4 1.2…1.9 1.2…2.4

M 5 2.0…3.0 2.0…4.0

M 6 … 2.5…5.0

Products with head screw with hexagon

Thread Torque range

Steel screws

[Nm]

M 4 1.2…2.4

M 5 2.0…4.0

M 6 3.0…6.0

M 8 6.0…12

M 10 10.0…20

M 12 14.0…31

M 16 25.0…60

Two conductors in one terminal

The optimum solution in terms of alloca-ting conductors to individual circuits andmarking and organising individual func-tional units involves just one conductorbeing connected to each terminal.

If it is necessary to connect two conduc-tors with the same cross-section in oneterminal, then this may be carried out usingW-series terminals (screw connection).

DIN IEC 60999-1 does not prohibit theuse of twin ferrules for connecting twoconductors in one terminal point using Z-series terminals (tension springtechnology).

DIN IEC 60999-1 prohibits the use ofscrewless IDC terminals (I-series) forconnecting two conductors.

• Continuous current for twoconductors

The total current of two conductors mustnot exceed the continuous current of theterminal. The continuous current is themaximum current, which a terminal cancarry without the increase in temperatureexceeding 45 K.

• Rated insulation voltage

The rated insulation voltage of the terminaldoes not change when two conductorshave been connected correctly.

Cross-connection systems

Weidmüller’s WQV and ZQV cross-connectors are systems which are fullyinsulated and finger-safe in the event thatthey are directly (and inadvertently)touched; they are available with differentnumbers of poles (2-pole to 50-pole).Note: the rated voltage is always reducedwhen using cross-connections.

Cross-connections which have been cutoff do not, however, offer this protection ifthe cut edge is directly (inadvertently)touched.

Partition plates or end plates must beused with these cross-connections topreserve the rated voltage.

Terminals

Conductor connection with pressureclamp for large cross-sections

It is now no longer necessary to forceconductors with large cross-sections intothe terminal: they can be inserted simplyand easily into the terminal block. Allterminal types are available not only asindividual terminals but also in blockversions with three-, four- and five-poleblocks. All blocks are firmly screwedtogether to offer additional distortionresistance. Longitudinal holes in thebottom of the terminals allow for directassembly.

Terminal blocks can be screwed directly to mounting plates with a 25 mm grid.

Other advantages include:

• constant transfer of forces with self-adjusting connection system

• any mounting direction possible

• finger-safe (VBG 4) even with cross-connection

• extremely distortion-proof

Open cover and remove screw unit

Insert conductor and replace screw unit

Close cover and tightenscrew with Allen key


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Terminals

Tips during installation: When tightening the terminals, it isadvisable to hold up the conductor toavoid deformation to the mounting rail andto keep the foot of the terminal free oftorsion forces.

Stranded aluminium conductors areconnected to terminals using analuminium cable lug selected according toits conductor shape and connected byfollowing the instructions issued by thecable lug manufacturer.

Copper-plated aluminium washers arenecessary for the transition from alumi-nium cable lugs to the busbar of theterminals. This is the only way to ensurereliable transition from copper to alumini-um. The washers are fitted so that thecopper side is in contact with the busbarand the aluminium side with the aluminiumcable lug.

Use of aluminium conductors

solid round or sector-shaped

Terminal type Rated cross- section Reduced rated Thread size of Tightening torquecurrent when terminal screwconnecting an aluminium conductor

W-series mm2 „A“ NmWDU 2.5 2.5 20 M 2.5 0.5WDU 4 4 27 M 3 0.6WDU 6 6 35 M 3.5 1.2WDU 10 10 48 M 4 2.0WDU 16 16 64 M 5 3.0WDU 35 35 105 M 6 4.0WDU 70 70 163 M 8 10.0WDU 120 120 230 M 10 15.0SAK seriesSAK 2.5 2.5 20 M 2.5 0.5SAK 4 4 27 M 3 0.6SAK 6 6 35 M 3.5 1.2SAK 10 10 48 M 4 2.0SAK 16 16 64 M 4 2.0SAK 35 35 105 M 6 4.0

strandedW-seriesWFF 35 35 105 M 6 3.0WFF 70 70 163 M 8 6.0WFF 120 120 230 M 10 10.0WFF 185 185 300 M 12 15.5WFF 300 300 409 M 16 30.0

Weidmüller terminals are suitable for thedirect connection of solid round andsector-shaped aluminium conductors.

Unlike copper, aluminium has certainmaterial properties, which have to betaken into consideration when it is used asa conductor in electrical systems.

When exposed to air, the bare surface ofthe aluminium immediately becomescovered with a thin, non-conductive layerof oxide. This increases the contactresistance between the aluminiumconductor and the busbar in the terminal.In the worst case, this may develop into aso-called glowing contact.

In the case of stranded conductors, thisphenomenon is exacerbated by thecontact resistance of the individual wires.

Despite these disadvantageousproperties, aluminium conductors can beconnected to Weidmüller terminals if thereduced rating currents for aluminiumconductors and the following assemblyinstructions are observed:

1. Carefully clean the oxide layer from thestripped end of the conductor, forexample using a knife. Caution: do not use brushes, files orsandpaper, to which aluminium particlesmay adhere and be transferred to otherconductors.

2. Immediately after removing the oxidelayer, rub neutral grease – such as acid-and alkali-free Vaseline – into the end ofthe conductor and connect it directly tothe terminal.

3. After disconnecting the conductor,repeat 1 and 2 prior to reconnection.

4. The instructions only apply to solidround or sector-shaped aluminiumconductors.

Aluminium

conductor

Busbar

Copper-platedaluminium washer

Aluminium side

Copper side

Fastening screw

Aluminium cable lug


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A PE terminal is a component with eitherone or several clamping positions forconnecting and/or branching PE con-ductors (PE and PEN conductors) with aconductive connection to their support.Partially insulated PE terminals areinsulated from adjacent live parts ofterminals; the partial insulation is markedgreen/yellow.

Scope (IEC 60947-7-2)

This standard applies to PE terminals (withPE function) up to 120 mm2 and to PEterminals (with PEN function) for sizesupwards of10 mm2 with screw clampingpoints or screwless clamping points forconnecting round copper conductors witha cross- section between 0.2 mm2 and120 mm2 (AWG 24/250 kcmil) for circuitsup to 1000 Vac 1000 Hz or up to 1500Vdc. PE terminals are used to produce theelectrical and mechanical connectionbetween copper conductors and thefastening base.

PEN function

Acc. to IEC 60947-7-2, only coppermounting rails may be used for applicationof the PEN function. Steel mounting railsmust not be used.

Einsatz der TS 35 x 15

Use of TS 35 x 15

In order to comply with the currentcapability required by IEC 60947-7-2, theTS 35 x 15 mounting rail must be used forPE terminals with a rated cross-section of16 mm2 and upwards.

A multi-storey distribution terminal is a unitwith clamping points for connectingand/or linking external, neutral and PEconductors to their fastening support witha conductive PE connection.

These terminals can be fitted on top of ornext to each other and assembled to formterminal strips.

They have several connection levels, all ofwhich are isolated from each other.

Scope IEC 60947-7-1 / IEC 60947-7-2DIN VDE 0611-4 (partially)

These standards apply to multi-storeydistributor terminals with clamping pointsand screw connections, and/or screwlessconnections for connecting or linkingsolid, stranded or flexible copperconductors. In distributor terminals,external conductor and/or N and PEconductor connections are all presenttogether within a confined space.

The N-conductor can be divided forinsulation measurement; it is not used for disconnecting or switching.

PE terminals

Definition of the various types

Multi-storey distribution terminals

Fuse terminals consist of a terminal baseand a fuse insert holder.

In the case of fuse terminals for low-voltage fuse inserts (D-system), thetechnical data are defined by IEC 60947-7-3 in conjunction with VDE 0636part 301.

In the case of fuse terminals for deviceprotection fuse inserts, the technical dataare defined by standard IEC 60947-7-3pertaining to the specific range ofapplications of these products.

Fuse terminals for device protection arerated for a certain maximum power losson the basis of standard IEC 60127-2valid for G-fuse inserts.

The product pages contain details aboutthe maximum power loss for individual orcomposite arrangements for short-circuitand/or overload protection.

Fuse terminals

Terminals

PE

TN-C system supplyfrom 16 qmm

PEN-bridgeWQB


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A neutral conductor disconnect terminal isa unit with clamping points for connectingand/or linking neutral conductors withdisconnect connection.

These terminals can be fitted on top of ornext to each other and assembled to formterminal strips.

Rated voltageIEC 60947-7-1IEC 60947-1

The rated voltage given conforms to IEC60947-7-1. It is the rated insulationvoltage and is defined acc. to IEC 60947-1or IEC 60947-7-1.

400 V applies toexternal conductor / external conductor

250 V applies toexternal conductor / N-conductorexternal conductor / PE conductorN-conductor / PE conductor

Neutral conductor isolating terminals

Measuring and isolating terminals areused for partial disconnection of circuitsfor measuring purposes in unloaded state.

The rated voltage of the measuring andisolating terminal is the rated insulationvoltage, to which the insulation tests andcreepage distances refer.

It is defined acc. to IEC 60664-1 and isone of the specifications marked on theterminal.

The opened disconnect point isdimensioned according to the allocatedrated surge voltage.

Isolating terminals are used for operationaldisconnection of circuits in unloaded state.

The rated voltage of the isolating terminalsis the rated insulation voltage to which theinsulation tests and creepage distancesrefer, and is defined acc. to IEC 60664-1.

The opened disconnect point is dimen-sioned acc. to the rated surge voltageallocated for devices with disconnectfunction acc. to DIN VDE 0100-537 andIEC 60947-7-1.

The disconnects of the isolating terminalsare rated for unloaded actuation (usecategory AC20 acc. to IEC 60947-1) andused to clear a system or part of asystem.

Measuring and isolating terminals Isolating terminals

Terminals

NT

Definition of the various types


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Ex terminals

Confirmed according to the new European Ex-Directive 94/9/EC – ATEX –

Terminals

MarkingEx-RL94/9EG: T II 2 G DT Ex electrical equipmentII 2 G Equipment group II category 2 (zone 1 electrical

equipment)II 2 D Equipment group II category 2 (zone 21 electrical

equipment)EN 50014/19: EEx e IIE Conformity with EN standardsEx Explosion protectione Increased safetyII Equipment groupKEMA 97ATEX4677U (Example)KEMA Notified bodyATEX Conformity with 94/9/ECU Component

Basic specificationsIEC 60947-7-1 (EN 60 947-7-1/ VDE 0611P.1) and IEC60 947-7-2 (EN 60 947-7-2/ VDE 0611P.3) are the basic specifi-cations for terminals, and also protective conductor terminals. For use in potentially explosive atmospheres the followingstandards also apply: EN 50 014 (IEC 60 079-0/VDE 0170/0171 P.1) and for increased safety “e” EN 50 019(IEC 60 079-7/ VDE 0170/0171 P. 6). Ex terminals are so-called Ex-compo-nents according to EN 50014.

Components means any item essential to the safe functioningof equipment and protective systems, but with no autonomousfunction.

Components according to the Ex-directive 94/9/EC are notmarked with CE.

Ex terminals are certified for the type of protection increasedsafety “e”.

According to the directive 94/9/EC, the European notified bodies have been issuing EC-type examination certificates ofthe so-called ATEX-Generation since 1997 in accordance withEN 50014 / 50019 and the Ex directive 94/9/EC.

A prerequisite is a notification of the manufacturer’s quality sy-stem. This exists for Weidmüller since 1997. Copies of thesetype examination certificates, the notification document and thedeclarations of conformity are available on request in electronicform.

The former component certifications (A to D generation) accor-ding to the Ex directive 76/117/EEC are still valid until30/6/2003.

The clamping yoke, tension clamp and IDC clamping system ofthe terminals provide increased protection against self-release,and are so designed that conductor ends of flexible conductorsdo not have to be pre-prepared. The cross-sections andconnection data specified in the selection tables are included inthe certification.


1.5 17.5 15.225 15 2.5 24 20.88 21 4 32 27.84 28 6 41 35.67 36

10 57 49.59 50 16 76 66.12 66 25 101 87.87 88 35 125 108.75 109 50 150 130.5 131 70 192 167.04 167 90 232 201.84 202

120 269 234.03 234 150 309 268.83 267 185 353 307.11 307 240 415 361.05 361 300 520 452.4 452

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Design for EEx iTerminals for “i” intrinsically-safe circuitsare passive components, whose tempera-ture-rise behaviour and the electrical cha-racteristics are known.

Therefore, there is no requirement for cer-tification when being used in intrinsically-safe circuits.

The terminals are light blue to ensure clearidentification and easy recognition.

These terminals conform to the construc-tion type as terminals corresponding tothe EEx e specifications.

AccessoriesThe accessories listed in the tables can beused and conform to EN 50 020 (IEC 60 079-11/VDE 0170/0171 P. 7).

MountingThe general statements also apply here forEEx i applications. Additionally, the EEx irequirements always apply to the comple-te circuit, therefore also for parts in non-potentially explosive atmospheres.

Clampability of 2 conductors in EExeFor our W-series terminals, it is fundamen-tally permitted to connect 2 wires to eachclamping point. It is, however, necessaryto use the next size down from the ratedwire cross-section. For detailed infor-mation see section “Terminals”.

VDE 0298 Part 4 (IEC364-5-523) Current carrying capacity of conductors

Ambient temperature 30 °CRouting type C + 3

for PVC 70 °C conductors

A

EN 50019 2nd. edtitionIncreased-safety type of pro-tection connection terminalsAmbient temperature 40 °C

40 K riseCurrent equivalent toconnect conductor

A

Ambient temperature 40 °CFactor 0.87

Routing type C + 3for PVC 70 °C conductors

A

Current carrying capacity of cables and conductors

Rated currents

Cross-section

Electrical dataThe specified values of the current carry-ing capacity are related to an ambienttemperature of 40 °C. At rated currentload (+ 10%), the temperature of thecurrentbar of the terminal increases by a maximum of 40 K.

Recognizing an additional factor of safetyaccording to EN 50 014, gives the follow-ing results:

Temperature class Ambient temperature

T6, T5 – 50 °C to + 40 °C

T4 to T1 – 50 °C to + 55 °C

If the real ambient temperature is higher,the permitted operating current must bereduced accordingly. As defined inEN 50 014, the continuous operatingtemperature for Wemid and KrG is100 °C, for PA material 80 ºC.

The current carrying capacity of cables and conductors in the installation is normallyspecified at 30 °C ambient temperature according to VDE 0298 Part 4. At 40 °C, the operating current shall be reduced by a factor of 0.87.

Ex terminals

Confirmed according to the new European Ex-Directive 94/9/EC – ATEX –

AccessoriesThe accessories listed in the tables can be used, and are listed in the Ex certifi-cations. To maintain the creepage andclearance distances for “e”, end plates orpartitions should be used, as specified inthe table.

Terminals


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Family 1) Certificate no. Rated Rated Nominal voltage current cross-section

AKZ ... V A mm2

AKZ 1.5 SIRA 02ATEX3001U 175 15 1.5

AKZ 2.5 SIRA 02ATEX3001U 175 21 2.5

AKZ 4 SIRA 02ATEX3001U 275 28 4.0

BK ...

BK 2/E ... BK 12/E SIRA 01ATEX3247U 275 28 4.0

I-series / IDK ...

IDK 1.5N KEMA 02ATEX2241 U 275 15 1.5

I-series / IDU ...

IDU 1.5N KEMA 02ATEX2241 U 275 15 1.5

IDU 2.5N DEMKO 03ATEX134054 U 550 21 2.5

IDU 2.5N/ZF DEMKO 03ATEX134054 U 550 21 2.5

IDU 2.5N/ZB DEMKO 03ATEX134054 U 550 21 2.5

IDU 1.5 TE/E KEMA 99ATEX4329 U 275 15 1.5

IDU 2.5 TE/E KEMA 99ATEX4329 U 275 21 2.5

MK ...

MK 3/.../E SIRA 01ATEX3248U 275 21 2.5

MK 6/.../E SIRA 01ATEX3249U 420 36 6.0

1) Please refer to the catalogue and the certificate showing precisely which article is approved.

Maximum voltage (V)(letters refer to the above diagrams)

A B C D E F G H I175 175 175 175 175 175 175 — —

175 175 175 175 175 175 175 — —

275 275 275 275 275 275 275 — —

175 175 275 175 — — 275 — —

275 275 275 275 — — — — —

275 275 275 275 275 275 275 275 —

550 420 550 550 550 550 550 550 —

550 420 550 275 275 550 275 550 —

550 420 550 275 275 550 275 550 —

275 275 275 110 275 275 110 275 —

275 275 275 110 275 275 110 275 —

175 175 275 175 — — — — —

275 275 420 275 — — — — —

A Continuous

ATEX cross-connection instructions

Arrangements of terminals and cross-connections

Maximum voltage

B AdjacentNot separated by a partition plate

or end plate

C AdjacentSeparated by a partition plate

or end plate

The maximum voltages for Eex e applications given below aredetermined on the basis of the terminals used, their cross-connectionand which of the arrangements A-J is used.

D SkippingBridging one or several not connected

terminals (e.g. every third)

E Adjacent to a PE terminal(earth) Without partition plate or end plate

I 3 parallel cross-connections

F Adjacent to a PE terminal(earth) With partition plate nor end plate

G Bridging a PE terminal (earth) H 2 parallel cross-connections

Terminals


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Family 1) Certificate no. Rated Rated Rated cross-voltage current section

SAK-series V A mm2

SAK 2.5 KEMA 97ATEX1798 U 550 21 2.5

SAK 4 KEMA 97ATEX1798 U 550 28 4.0

SAK 6N KEMA 97ATEX1798 U 550 36 6.0

SAK 10 KEMA 97ATEX1798 U 550 50 10.0

SAK 16 KEMA 97ATEX1798 U 750 66 16.0

SAK 35 KEMA 97ATEX1798 U 550 109 35.0

W-series / WDK ...

WDK 1.5/R3.5 KEMA 99ATEX6545 U 275 15 1.5

WDK 2.5 KEMA 98ATEX1687 U 275 21 2.5

WDK 2.5N KEMA 00ATEX2061U 550 21 2.5

WDK 4N KEMA 00ATEX2061U 550 28 4.0

W-series / WDU ...

WDU 1.5/ZZ KEMA 98ATEX1685 U 550 14 1.5

WDU 2.5/1.5/ZR KEMA 98ATEX1685 U 550 15 1.5

WDU 2.5/TC SIRA 02ATEX3153 U 50 15 1.5

WDU 1.5/R3.5 KEMA 99ATEX6545 U 275 1 2.5

WDU 2.5N KEMA 98ATEX1683 U 420 21 2.5

WDU 2.5 KEMA 98ATEX1683 U 550 21 2.5

WDU 4 KEMA 98ATEX1683 U 750 28 4.0

WDU 6 KEMA 98ATEX1683 U 550 36 6.0

WDU 10 KEMA 98ATEX1683 U 550 50 10.0

WDU 16 KEMA 98ATEX1683 U 750 66 16.0

WDU 35 KEMA 98ATEX1683 U 750 109 35

WDU 70N/35 KEMA 98ATEX1683 U 750 167 70

WDU 70/95 KEMA 98ATEX1686 U 750 202 70

WDU 120/150 KEMA 98ATEX1686 U 1100 234 120

WDU 240 KEMA 01ATEX2186 U 750 300 240

WDU 4 SL SIRA 02ATEX3242 U 275 28 4

WDU 6 SL SIRA 02ATEX3242 U 275 36 6

WDU 10 SL SIRA 02ATEX3242 U 275 50 10

Stud terminals / WFF ...

WFF 35 KEMA 98ATEX1684 U 1100 109 35

WFF 70 KEMA 98ATEX1684 U 1100 167 70

WFF 120 KEMA 98ATEX1684 U 1100 234 120

WFF 185 KEMA 98ATEX1684 U 1100 307 185

WFF 300 KEMA 98ATEX1684 U 1100 452 300

Z-series / ZDK ...

ZDK 2.5/1.5 KEMA 97ATEX4677 U 275 18 2.5

Z-series / ZDU ...

ZDU 1.5 KEMA 01ATEX2106 U 550 15 1.5

ZDU 1.5/3AN KEMA 01ATEX2106 U 550 15 1.5

ZDU 1.5/4AN KEMA 01ATEX2106 U 550 15 1.5

ZDU 2.5 KEMA 97ATEX2521 U 550 21 2.5

ZDU 2.5/2X2AN KEMA 97ATEX2521 U 550 21 2.5

ZDU 2.5/3AN KEMA 97ATEX2521 U 550 21 2.5

ZDU 2.5/4AN KEMA 97ATEX2521 U 550 21 2.5

ZDU 4 KEMA 97ATEX2521 U 550 28 4

ZDU 6 KEMA 97ATEX2521 U 550 36 6

ZDU 6/3AN KEMA 00ATEX2107 U 550 36 6

ZDU 10 KEMA 99ATEX5514 U 550 50 10

ZDU 10/3AN KEMA 00ATEX2107 U 550 50 10

ZDU 16 KEMA 99ATEX5514 U 550 66 16

ZDU 16/3AN KEMA 00ATEX2107 U 550 66 16

ZDU 35 KEMA 00ATEX2107 U 750 109 35

ZDU 2.5-2/3AN KEMA 97ATEX4677 U 550 21 2.5

ZDU 2.5-2/4AN KEMA 97ATEX4677 U 550 21 2.5

ZDUA 2.5-2 KEMA 97ATEX4678 U 275 20 2.5

ZDUB 2.5-2/... KEMA 97ATEX2755 U 550 21 2.5

1) Please refer to the catalogue and the certificate showing precisely which article is approved.

Maximum voltage (V)(letters refer to the above diagrams)

A B C D E F G H I550 550 550 175 550 550 175 — —

550 550 550 175 550 550 175 — —

550 550 550 175 550 550 175 — —

550 550 550 175 550 550 175 — —

550 550 550 175 550 750 175 — —

550 550 550 175 550 550 175 — —

175 175 275 175 175 — — — —

275 275 275 60 275 275 60 — —

550 550 550 275 550 550 275 — —

550 550 550 275 550 550 275 — —

550 550 550 110 550 550 110 110 —

550 550 550 110 550 550 110 110 —

— — — — — — — — —

175 175 275 175 175 — — — —

420 420 420 110 420 420 110 — —

550 550 550 110 420 550 110 110 2) 60 3)

750 750 750 110 420 750 110 — —

550 550 550 110 420 550 110 — —

550 550 550 110 420 550 110 — —

750 750 750 110 750 750 110 — —

750 750 750 110 750 750 110 — —

750 750 750 — 750 750 — — —

750 750 750 — 750 750 — — —

1100 1100 1100 — 1100 1100 — — —

— — — — — — — — —

275 275 275 175 275 275 175 175 —

275 275 275 175 275 275 175 175 —

275 275 275 175 275 275 175 175 —

1100 1100 1100 — 1100 1100 — — —

1100 1100 1100 — 1100 1100 — — —

1100 1100 1100 — 1100 1100 — — —

1100 1100 1100 — 1100 1100 — — —

1100 1100 1100 — 1100 1100 — — —

275 275 275 275 275 275 275 — —

275 275 275 175 275 550 175 275 —

275 275 275 175 275 550 175 275 —

275 275 275 175 275 550 175 275 —

275 275 275 275 275 275 275 275 —

— — — — — — — — —

275 275 275 275 275 275 275 — —

275 275 275 275 275 275 275 — —

275 275 275 275 275 275 275 275 —

275 275 275 275 275 275 275 275 —

275 275 275 275 275 275 275 — —

550 550 550 — 550 550 — — —

550 550 550 275 550 550 — — —

550 550 550 — 550 550 — — —

— — — — — — — — —

550 550 550 — 550 750 — — —

420 420 420 275 550 550 275 110 —

— — — — — — — — —

275 275 275 110 275 275 110 — —

— — — — — — — — —

2) For ZQV, the outer channels must be used in these cases.3) Only possible with ZQV.

Maximum voltage

Terminals


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Owing to their universal foot design,Weidmüller relay modules can be fittedtogether on the TS 32, TS 35 x 7.5 andTS 35 x 15 mounting rails in accordancewith the European standards EN 50 035and EN 50 022. In the coil circuit of therelay module, an LED status displayindicates the switching state of the relay.

Relay couplers

Contact types

Several types of contact andcombinations are available ex stock.

1 NCC EGR EG2, EGR EG7,RS 30

1 NOC EGR EG2, EGR EG7,DKR, RS 30

1 NCC and EGR EG2, WRS1 NOC

2 NOCs WRS

3 NOCs WRS

1 change-over EGR EG2, contact EGR/RST EG7, WRS,

DKR, PRS/PRZ MCZ R,RS 30, RS 31

2 change-over EGR EG2, WRS, contacts RS 32, PRS/PRZ

4/8/16 change- RSMover contacts

Arrangement of the contacts in aprotective circuit

When switching inductive or capacitiveloads, switching functions occur whichinfluence the electrical service life of therelays.

Wear in the contacts can be reduced byusing the following protective circuits:

Diode:

Advantage: Can be used for all power ratings, low overvoltage, minimum spacerequired, low cost

Disadvantage: Very considerable release delay

Diode and Z-diode:

Advantage: Low overvoltage (as determined byZ-diode), only slight release delay

Disadvantage: Cannot be used for large powerratings

RC combination:

Advantage: Low overvoltage, only slight releasedelay

Disadvantage: Higher current load on contactswhen switching on, more compli-cated and expensive at higherpower ratings

Varistor:

Advantage: Only slight release delay, low costDisadvantage: Cannot be used for all operating

voltages and power ratings

US voltage curve1 closing2 opening

UVDRLast

+–

(~)(~)

VDR

US

1 2 t

URCLast

+–

(~)(~)R

C

US

1 2 t

UZDLast

+–US

1 2 t

UDLast

+–US

1 2 t

Load

Load

Load

Load

Switching small and large powerratings

For automation technology, Weidmüllersupplies EGR EG7 relay couplers forswitching the smallest power ratings (upto 40 µW) under resistive load, so that thesignals can be reliably transferred tocontrollers.

The RS31 relay coupler is used forswitching large power ratings in theenergy and supply industry. It guaranteesa switching power rating of up to 3.5 kVAunder resistive load.

Switching times of the relay modules

Response delay typically < 10 msRelease delay typically < 12 ms

Switching behaviour/load limit curves(depending on type)

Contact service life under resistive load

dc load limit curve under resistive load

Reduction factor

under inductive load cos � < 1

No. of cycleseff = no. of cycles (at cos � < 1) x reduction factor F


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Relay couplers

Relay couplers with plugged relay

Relay couplers with plugged relay are ofonly limited suitability in an environmentsubject to extreme vibrations. Preferenceshould be given to relay couplers withsoldered relay.

Derating curve

The contact resistance of the relaycontacts is a key factor contributing totemperature increase inside relaymodules. This relationship is illustrated bya derating curve, produced by plottingtolerable current against ambienttemperature.

The current (Curve a) is determined for the following operating conditions:

– Continuous operation

– Rated input voltage +10%

– Several relay modules working underload without any spacing, mountedhorizontally on a mounting rail

When the modules are mounted withspacing > 20 mm, this results in a highercurrent load (Curve “b”). The function “b”also indicates the maximum values forswitching or short-term operation in thehorizontally mounted state.

Notes on application

The triggering parameters must beprecisely adhered to when using UCversions in dc circuits. Owing to their pre-circuitry, UC versions consume morecurrent at the moment they are switchedon. The internal current limit of thestandard initiators available may meanthat the triggered relay couplers are notswitched through.

Relay couplers with 24 V ac/dc input arenot suitable for triggering by initiators.Here we recommend using a purely dcversion.

RC combinations

Long leads are particularly prone toelectrical and electromechanicalinfluences.

This may lead to malfunctions and evenfailure of the relay module. An upstreamRC combination can prevent this byfiltering out the interference.

RC combinations are available for allcommon relay couplers, either plug types(PLUGSERIES) or as terminals WDU 12Cand DKU 12C.


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Opto-couplers

Basic structure of the opto-couplerinterface:

The key component is the actualoptoelectronic component (opto-coupler),which is responsible for the coupling.

One important variable of this componentis the current transfer rate (CTR).

The CTR factor is stated as a percentageand describes the relationship betweendispensed input current IF and themaximum available output current IC.

Example: IF = 10 mA; CTR = 100 %=> IC = 10 mA.

However, the CTR is influenced by certainparameters, which cause it to decreaseover time, such as:– ambient temperature– degree of efficiency of the luminiscence

diode– geometric dimensions within the

component

In consequence, the switching thresholdsalso change over time (although this ispartly the result of aging).

CTR curve over operating time

To eliminate this effect as far as possible,Weidmüller almost exclusively usesoptoelectronic semi-conductors with highlong-term stability in terms of CTRbehaviour.

The insulation strength of the componentis also important, because this is wherethe actual coupling of the input and outputcircuits takes place by optical transfer.This means that even in the event of afault, the optical component mustguarantee separation of both circuits.

By using opto electronic couplingelements in accordance with DIN VDE 0884, Weidmüller’s opto-couplersoffer the highest possible safetystandards.

The circuitry within the module as a wholemust also be considered, so that theentire module complies with DIN VDE 0106 part 101, for example in termsof “protective separation”.

Basic circuit diagram of the opto electroniccomponent

Opto-couplers for galvanic or“protective separation”

The chief prerequisite for “protectiveseparation” with optoelectronic couplermodules is the partial discharge level testacc. to DIN VDE 0884. Double orreinforced insulation for “protectiveseparation” must be resistant to partialdischarge. High-voltage testing, astandard procedure for relays, is notpossible with semi-conductors because itmay actually destroy them. In the case ofcoupler modules with integrated opto-couplers, “protective separation” for thestated rated voltage is achieved when thefollowing requirements are satisfied:

– Opto-couplers tested to DIN VDE 0884– Creepage and clearance distances on

circuit boards and connection elementscomply with EN 50 178, DIN VDE 0106or 0109

Owing to the increasing degree ofautomation, the electrical isolationbetween control circuits (control side /field side) is becoming increasinglysignificant. The connection between thecontroller, which is the key component ofevery automated system, and the varioussensors and actuators must be electricallysafe and free of any feedback. Opto-couplers are finding increasing use here.They provide the necessary degree ofsafety and have additional beneficialfeatures such as:

– Low power consumption on thecontroller side

– High switching frequency– No contact bounce– Wear-free switching– Insensitive to vibrations– Can be used position insensitivity– No mechanical parts– Long service life– High insulation voltage

These properties make opto-couplers agood alternative to the classical,mechanical relay interface.

Weidmüller offers modules with differentinput voltages and enclosure technologiesfor industrial use.

Inputcontrolcircuit

Outputcontrolcircuit

Receiver

t ( service life)

CTR asa %

Sender


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Opto-couplers

Controller side of the opto-couplerinterfaceA distinction is made between three basiccircuits on the input side of the opto-coupler interfaces

– Pure dc input: Here there is a polarityreversal protection diode, whichprevents damage to the module in thecase of reversed input polarity

.

– ac/dc input:

Here it is not possible to reverse thepolarity of the dc input signal. Thedisadvantage of the ac/dc input circuit(with dc signal trigger) is the lowerswitching frequency of the module,because the charge capacitor (CL,necessary for ac input signals) reducesthe maximum switching frequency.

– AC input:

Here again, the charging capacity has amajor influence on the maximumswitching frequency of the module as awhole.

Weidmüller Opto-couplers with ac/dc orac input signals are rated for mainsfrequencies of approx. 40 …. 60 Hz. Inthe case of ac input signals, the maximumswitching frequency of the opto-couplermodule is less than half the mainsfrequency. A higher switching frequency isnot possible, because this would result inconstant switching in the rhythm of themains frequency.

Load side of the opto-couplerinterface

Weidmüller opto-coupler modules havebeen rated and developed for variousdifferent applications.

Possible demands made of the load sideof the opto-coupler modules include:– power amplification– ac/dc and dc/ac signal conditioning– short-circuit protection– interference immunity.

To meet these requirements, the modulesare assembled with additional electronicelements, which then define the overallfunctioning of the opto-coupler module.

Accordingly, there are always two versionsof the load side of the opto-coupler:output as – 2-pole or – 3-pole circuit

2-pole dc output

The 2-pole dc output can be comparedwith a conventional switch. In this version,it does not matter where the load islocated (in the output circuit), although thenecessary output supply voltage must beavailable with the right polarity.

*switching possibility

*switching possibility

Opto-coupler modules are usuallyspecified as having an output supplyvoltage range such as 5 … 48 Vdc. The voltage should on no account ever be higher or lower than these values. Theload current should not be higher than thestated maximum output current. If thisvalue were constantly exceeded, theoutput level would be destroyed.

Derating diagrams show the relationship of output current to ambient temperature(indicated for the products on the followingpages).

2-pole ac output

A special semi-conductor module (TRIAC)is used for switching ac voltages in theoutput level of the optocoupler. Here, aswith the dc output , consideration mustalso be given to the key data (voltage,frequency, maximum load current, ambienttemperature, etc.).

Use of the zero voltage switch ensures that load is only switched on at the zerocrossover of the voltage. The modules arealways equipped with suitable protectionelements (varistor, RC combination) asprotection from non-permissible voltagepeaks.

circuit example

Zero

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Opto-couplers

3-pole dc output

In order to function safely, this kind ofoutput level required potential-relatedoutput supply voltage with a single output.It is rated for either positive switching (jointreference potential: GND or 0V) ornegative switching (joint referencepotential: positive voltage pole).

Standards:The following standards are compliedwith:

EN 50178:Electronic equipment for use in powerinstallations

DIN VDE 0106 part 101Protection from dangerous body currents,basic requirements for “protectiveseparation” in electrical equipment

DIN VDE 0884Optoelectronic couplers for “protectiveseparation”

DIN VDE 0109Insulation coordination for equipmentwithin low-voltage systems, includingclearance and creepage distances forconfigured printed circuit boards

Protection circuitsAll opto-coupler modules have a protectioncircuit in the output (usually with a recoverydiode).

The load side must be protected toprevent interference signals from couplinginto other lines.

Protective circuit for dc output

Protective circuit for ac output (for more details see“Over-voltage protection”, chapter 7).

Application exampless

Position message with Namur initiator

Monitoring an actuator

InputsPLC PLC

Inputs

Opto-coupler outputOpto-coupler output

Opto-coupler inputOpto-coupler input

protection

protection

load

load

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Overvoltage protection

The electronic equipment of electricalsystems is becoming increasinglycomplex.

Programmable logic controls and PCapplications are replacing connection-programmed controls (relay technology).

Faults caused by overvoltage or switchingoperations in the systems may causefailure or damage of the system parts.

Suitable overvoltage protection measurescan almost fully eliminate such problems.

Protective elements

Voltage-limiting protective elements:

• Gas-filled gas charge eliminators

• Voltage-dependent resistances(varistors)

• Voltage-dependent diodes (suppressor diodes)

The gas charge eliminator consists of aninsulating body (a metallised aluminiumoxide tube or glass tube), with vacuum-tight connections to two or three electro-des made of special alloys. The gascharge eliminator, which is filled with inertgas, conducts to earth the energy asso-ciated with the overvoltage and, at con-nection voltages < 100 V and short-circuitcurrents < 0.1 A, reverts to its high-resistive state once the overvoltage hassubsided. A pre-fuse is required.

The gas charge eliminators used byWeidmüller are not tritium-doped.

In compliance with CCITT (Volume IV,K.12) and DIN 57845/VDE 0845, thenominal data for the gas charge eliminatorare given in the catalogue.

DC operating voltage:

This is determined at a du/dt of approx.100 V/s (static behaviour), with a toleranceof up to + 20 %.

Impulse sparkover voltage:

This is determined at a du/dt of approx.1000V/µs (dynamic behaviour). Typical values are < 800V.

Leakage current:

Here two procedures are used: DIN VDE 0432 part 2, IEC 68 and CCITT.

CCITT: 10 loads (8/20 µs) at 3-minuteintervals or acc. to VDE: 5 loads (8/20 µs)at 30 s intervals.Typical values are 5, 10, 20 kA.

DIN IEC 68 states the mechanical/climaticconditions under which the mechanicalconditions are verified. These includevibrations, shock, and the climatic con-ditions for the gas charge eliminators, e.g.part 2-3 humidity/temperature for 21 days, 40 °C, 93 % rel. hum., operatingtemperature range – 40 °C … + 90 °C.

The typical capacity of the gas chargeeliminator is several pF.

Gas charge eliminator Varistors

These voltage-dependent resistors consistof zinc oxide. Varistors are available indifferent types, with disk varistors the pre-ferred form. If the varistor is connected tothe maximum tolerable voltage, then a faultcurrent of just a few µA flows through it.

Varistors are tested by the manufacturerto DIN IEC 68 and according to the qualityconfirmation system CECC 42000 (DIN 45923).

DIN IEC 68 names the mechanical/climatic conditions according to which themechanical conditions are verified. Theseinclude for example vibrations and shock,together with the climatic conditions forthe varistors, e.g. part 2-3 humidity/ temperature for 56 days, 40 °C,93% rel. hum., operating temperaturerange – 40°C … + 90°C.

Storage temperature to + 125°C.

CECC 4200 covers specifications such asvoltage strength (> 2.5 kW), surge currentderating (8/20 µs), insulation resistance > 1 GOhm and the typical response time< 25 ns.

When the varistor is operated at standardmains impedances, varistor types S14 orS20 should be used.

S14 can be protected by a fuse of max.10A, S20 with max. 16A.

The energy absorption (2ms) of thevaristors ranges from 0.3J to approx.200J depending on the type.

The capacity of the varistors depends on the type, ranging from 0.1 to 37 nF at 1 kHz.

1

kV

0,5

1 ∝s

t

1

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0,5

1 ∝s

tInput pulse Output pulse

U

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Varistor approvals Suppressor diodes Combination circuits

– Underwriters Laboratories, Inc. (UL)

– UL 1414 across-the-line components:

– File E77005 (N) for type seriesS05/S07/S10/S14/S20, in voltagestages K130 to K300

– UL 1449 transient voltage suppressors:File E77005 (M): all disk types preferablyintegrated within DKU, EGU, PLU, RSU

– Canadian Standards Association (CSA)

– Class 221 01 Accessories and Parts forElectronic ProductsAll disk types with a voltage > 115 V; for use as across-the-line transientprotectors: file LR 63184

– Schweizerischer ElektrotechnischerVerein SEV

– Protection class I, protection rating IP00,test regulations CECC 42200, testreport no. 90.1 02484.01 dated 17.7.91for type series S05/S07/S10/S14/S20

Suppressor diodes work similarly to zenerdiodes, but in this application they workmuch faster than zener diodes, withresponse times ranging from a few ps to 5 ns. Energy absorption (1 ms) of thesuppressor diodes ranges from 0.3 J to1.5 J depending on the type.

The typical capacity of the diodes at 1 MHz ranges from 9500 pF to 360 pF.

Depending on the type, the suppressordiodes can convert max. 1500 W intoheat for power of 1 ms duration. If thediode is overloaded, the P-N contactcloses briefly. If the energy supplycontinues, the P-N contact self-destructs.

These diodes can be used in applicationssuch as protective circuits for coils or incombination with gas charge eliminatorsand varistors.

Suppressor diodes are supplied as uni-directional and bi-directional types. In the24 Vdc overvoltage protection module,Weidmüller frequently uses the uni-directional diodes. This adjusts the typicalvoltage values in the blocked direction to29 A and 0.7V in the passage direction.

U

t

U


U

100

V

200

300

400

500

600

00 1 2∝s

∝s∝s0

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8

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20 40 60

UB

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00

Voltage curve at protection circuit EGU2

Combinations of the above mentionedindividual components result in fineovervoltage protection modules which canbe customised to meet individualdemands. If a voltage pulse reaches theinput of this unit, then the gas chargeeliminator ignites and discharges a highcurrent. The remaining pulse is attenuatedby a downstream inductor and then takenup and limited by the varistor orsuppression diode. If the gas chargeeliminator does not respond, i.e. voltageincreases more slowly, then the pulse isprocessed only by the varistor or diode.

The sequence of individual componentsresults in an increase in responsesensitivity in the output direction. Aninterference voltage with an increase of 1 kV/µs and a peak of 10 kV at the inputis limited to approx. 600 – 700 V by a gas-filled surge arrester.

The second stage, which is decoupledfrom the first by an inductor, then limitsthis value to approx. 90 V.

The voltage pulse is reduced by thesuppression diode to approx. 35 V for a 24 V module.

The following electronic component istherefore only required to withstand avoltage pulse of approx. 1.5 x UB.


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Applications for fine overvoltageprotection in instrumentation andcontrol engineering

Overvoltages on instrumentation andcontrol signals and on data and powersupply lines can cause considerableinterference with operations.

Under certain circumstances, failure of theelectronic systems or entire installationsmay have serious consequences, evenincluding personal injury.

Among the causes of overvoltages areatmospheric discharge and switchingprocedures. Overvoltages are relevant inthe following areas:

� Remote engineering

� Signalling systems

� Data processing systems

� Process terminals

� Control engineering

� Meteorological stations

These installations must be protectedfrom overvoltage.

Application areas for fine overvoltageprotection:

� In instrumentation and control stations,field lines coming in from sensors andactuators have to be protected fromovervoltage, as do the sensors them-selves.

� Power stations, water treatment plantsor sewage plants must be protectednot only from direct lightning strikes butalso from the remote effects of light-ning. The large area covered by theplant and the extensive electrical in-stallations used to encompass this areamust be equipped with fine overvoltageprotection.

� It is essential in the interests of safetythat traffic engineering systems, suchas locks and signal systems, beequipped with overvoltage protectionmodules.

� Machines controlled by frequencyconverters modulate mains voltageswith high-frequency interference, thusinfluencing other electronic modules.

� Power supply lines and data lines fromcomputers and their peripheralequipment must be protected to allowfor safe, reliable operation.


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Installation of overvoltage protectioncircuits

Introduction:Overvoltage protection in terminalformat:Mini-conditioner

Combination circuits

The above components can be combinedto produce highly effective overvoltageprotection terminals (MCZ OVP). The gascharge eliminators can discharge highcurrents.

The varistors and suppressor diodesabsorb the residual voltage, and theintegrated inductors are responsible for de-coupling.

The energy is discharged via a TS con-tact. In addition, a tension clamp isavailable for PE connection.

Mounting rail contact

Contact with the mounting rail is producedautomatically by snapping the com-ponents on.

The TS 35 must be earthed for energydischarge of up to 10 kA (8/20µs) via theMCZ terminals. For EMC-related reasons,the mounting rail is screwed to theearthed mounting plate. In addition, thePE contact can be produced by thetension clamp of the MCZ OVP.

Application

The MCZ OVP 24 Vdc CL, an overvoltageprotector for current loops, has a fast-switching (10-100 ps) suppression diode in its output. When overvoltage occurs, this diode clamps the voltage within thecurrent loop, thus preventing damage tothe sensor or actuator.

Use

A protection concept for the installationmust involve all leads being protected withovervoltage protection products.

Overvoltage protection for powernetworks (PU B / PU C)

The MCZ OVP has tension spring con-nection terminals for fast wiring of instru-mentation and control leads. Dischargetakes place directly via a contact to themounting rail. The contact is producedautomatically as soon as the MCZ OVP is snapped onto the mounting rail.

prevents damage to low-voltage consumerinstallations and electronic devices in theevent of overvoltage caused by atmos-pheric discharge (thunderstorms) or, much more frequently, switching activity(transients) in the network. The PUmodules attenuate strong pulses. Ininstrumentation and control circuits, theattenuated pulses can still causeinterference in the systems.

Hence the need for three-level overvoltageprotection terminals, with gas chargeeliminator, varistors, suppressor diodes(TAZ) and decoupling inducers.

Gas charge eliminators are overvoltageprotection discharges that involve adischarger. When overvoltage occurs, alight arc is ignited between electrodes, sothat the discharger passes suddenly (1 µs)from a high-resistance to a low-resistancerange.

Varistors are used for medium and largerpower ratings. Metal oxide varistors reduceresistance at excessive voltage. Thevaristor can become low-resistive within 25 ns, thus discharging the overvoltage.

Suppressor diodes work similarly to zenerdiodes but with a high pulse handlingcapability with response times of the order of a few ps.

The fine overvoltage protection modulesmust be installed in the immediate vicinityof the devices being protected. Theprotective earth of the device must beconnected to the fine overvoltageprotection modules.

� A cross-section between 2.5 mm2 and4 mm2 should be used for routing theearth leads.

� The connections should be kept asshort as possible.

� Avoid switching several earth lines inseries.

� The earthing systems should be ratedaccording to VDE 0100, VDE 0185,VDE 0800 and the Deutsche Telekomtelecommunications directive FBO 14.

Routing lines

The signal linesshould be routed inthe installation bythe shortest route tothe fine overvoltageprotection and thento the electronic

device. Avoid parallel routing with otherlines and avoid routing protected andunprotected lines together. (Caution isrequired with cable harnesses and cableconduits!).

If parallel routing is unavoidable, thereshould be spacing of at least 0.5 mbetween the lines.

Marking themodule

The overvoltageprotective module is marked with anarrow or labelled“IN”.

The arrow points to the protected side ofthe module, i.e. overvoltage is dischargedin the direction of the arrow (see combina-tion circuit).

3

2

1

6

5

4IN OUT


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Eliminators in requirements class B

Eliminators installed for the purpose oflightning protection equipotentialbonding, capable of coping with directstrikes of lightning. These eliminators aretested with a simulated lightning testcurrent/imp wave form 10/350 µs.

Eliminators in requirements class D

Eliminators installed for the purpose ofovervoltage protection in stationary ormobile installations, particularly formains sockets or terminal devices

Eliminators in requirements class C

Eliminators installed for the purpose ofovervoltage protection in stationaryinstallations, e.g. distributors. Theseeliminators are tested using a ratedleakage current isn, wave form 8/20 µs.

measure-ment

KWh 3 ≈

Eliminator (according to draftVDE 0675 part 6)

B10/350 µ2


C8/20 µs


D1.2/50 µs

Insulation coordination is rated for 6 kVin the 230/400 V mains. According toDIN VDE 0110, the overvoltage pro-tection must not be lower then class IV.

The B-eliminator is used for lightningprotection equipotential bonding when a lightning eliminator is fitted to thebuilding.

Insulation coordination is rated for 4 kVin the 230/400 V mains. According toDIN VDE 0110, the overvoltage pro-tection must not be lower than class III.

The C-eliminator is used for dischargingto earth the energy coupled into themains feed line. Used in switchboards

Insulation coordination is rated for 2.5/1.5 kV in the 230/400 V mainsnetwork. DIN VDE 0110 stipulates thatthe overvoltage protection must not be lower than class II.

The D-eliminator is used for dischargingto earth the energy coupled into themains feed line. Used in switchboards or sub-distributions.

Basic feed diagram

160 A

160 A

160 A

125 A

125 A

125 A 16 A

Requirement “for energy systems”

Overvoltage protection for 230 / 400 V electricity mains

Eliminators for electricity mains (230/400 V)are divided into four requirementcategories. Weidmüller has three groups ofeliminators in its product range


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3+1 circuit Overvoltage protection for TT networks with 3 varistors and one discharger. Prevents voltage entrainment when varistors are defective.

Eliminator Protective element which discharges energy symmetrically or asymmetrically.

Disconnect device Device which disconnects the eliminator from the mains in the event of a fault and indicates that a fault has occurred.

Ageing Change in the original rating data caused by interference, operation or unfavourable ambientconditions.

Requirements class B Stipulates the purpose of lightning protection equipotential bonding acc. to DIN VDE 0185-1; see also class 1.

Requirements class C Stipulates the purpose of overvoltage protection in stationary installations, preferably for use inimpulse withstand voltage category III; see also class II.

Requirements class D Stipulates the purpose of overvoltage protection in stationary installations, preferably for use inimpulse withstand voltage category II; see also class III.

Response time Reaction speed ranges from a few µs to times in the order of ps, depending on the type andstructure of the protection module.

Asymmetrical interference voltage Voltage between the “electric mid-point” and reference potential (earth).

Binary signals Switching signals with the status on and off.

Lightning surge current Iimp Defined by the peak current Ipeak and the load Q, when testing according to class I.

Continuous operating current Ic Current per protection path under operating voltage Uc.

Insertion loss Attenuation additionally contributed by an inserted four-pole.

EMC Electromagnetic compatibility.

FI protection switch If a fault current exceeds a certain limit, the FI switches off within 0.2 sec.

Subsequent current Ir Current flowing from the mains through the overvoltage protection device immediately after a discharge.

Galvanic coupling Interference source and use source have the same impedance (line connected).

Gas charge eliminator Voltage-dependent encapsulated switch with high current-carrying capacity.

Push-pull interference The interference source and source of use are connected in series (e.g. magnetic or galvaniccoupling).

Measured voltage limit Maximum voltage level during application of surges of prespecified form and altitude in testing.

Triggered discharger A gas-filled discharger ignited by a capacative attenuator at a preset voltage level.

Common-mode interference The interference source is between the signal wire and reference conductor (e.g. capacitive couplingor potential increase of physically separated earths).

Frequency limit Indicates the frequency up to which successful transfer occurs. At higher frequencies, the pro-tective circuit attenuates to such an extent that transfer is no longer possible.

Maximum operating voltage Uc Highest effective value of ac voltage or highest value of dc voltage tolerated continuously on theprotection path of the overvoltage protection device. Operating voltage = rated voltage.

Inductive coupling Coupling through two or three live conductor loops.

Insta Installation enclosure acc. to DIN 43880, suitable for integration of installation distributors.

Ipeak Peak current of a test pulse.

Isn Peak value of the nominal leakage current.

Insulation coordination Peak withstand current capacity of the insulation in installation components according to DIN VDE0110 part 1.

IT network Network system with 3 external conductors insulated to earth potential. The PE of the building isnot connected to the network system.

Capacitive coupling Coupling of interference circuit and use circuit via coupling capacitors caused by a difference inpotential.

Class I Stipulates the purpose of lightning protection equipotential bonding acc. to IEC 37A/44/CDV; seealso requirements class B.

Class II Stipulates the purpose of overvoltage protection in stationary installations, preferably for use inimpulse withstand voltage category III; see also requirements class C.

Class III Stipulates the purpose of overvoltage protection in stationary installations, preferable for use inimpulse withstand voltage category II; see also requirements class D.

Combination circuit Protection circuit made up (for example) of gas charge eliminator, varistor and/or suppressor diode.


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Combined surge The hybrid generator generates a 1.2/50 µs pulse in idle mode and a 8/20 µs pulse in short-cir-cuit. The ratio of peak value idle voltage Uoc to peak value short circuit current Isc is 2 ohms.

Short-circuit strength Highest non-influenced short-circuit current which the overvoltage protection device canwithstand.

Longitudinal voltage Interference voltage between active conductor and earth.

Leakage current Current which flows to PE under rated voltage.

Maximum discharge surge current Imax Peak value of current 8/20 µs during trial run of operational test acc. to class II.

MCZ ovp Narrow protective terminal with tension spring connection and mounting rail contact for PE.

MOV See varistor

MSR Instrumentation and control technology

Nominal discharge surge current In Peak value of surge current 8/20 during test acc. to class II.

PE Protection and earthing system to which the energy is discharged.

PU Overvoltage protection for high pulses in energy systems in installation enclosures.

Transverse voltage Interference voltage between two conductors of a circuit

RCD See FI protection switch

RSU Overvoltage protection on the clip-on base profile with gas charge eliminator, varistor andsuppressor diodes for 6A and 10 A current loops.

Degree of protection of the enclosure Degree of protection afforded by the enclosure to prevent contact with live parts and to preven(IP code) penetration of solid particles or water. Tested acc. to IEC 529 section 7.4

Protection level Up Indicates the residual voltage measured for an overvoltage pulse at the terminals (preferential valueas highest measured voltage limit). Important parameter characterising the efficiency of the over-voltage protection device.

Protection path Circuit of the components of an overvoltage protection device; “conductor to conductor”, “con-ductor to earth”, “conductor to neutral” and “neutral to earth” are all protection paths.

SPD Surge protection device

Surge voltage 1.2/50µs Surge voltage with a head time of 1.2 µs and a time to half value of 50 s

Surge current 10/350 µs Lightning test current with a head time of 10 µs and a time to half value of 350 µs.

Surge current 8/20 µs Lightning test current with a head time of 8 µs and a time to half value of 20 µs.

Radiation coupling Electromagnetic field coupled in one or several conductor loops.

Suppressor diode Voltage-dependent, fast-switching semi-conductor diode.

Symmetric interference voltage Voltage between push and pull conductor (push-pull voltage).

TAZ See suppressor diode.

TN-Netz Netzsystem als 4 oder 5 Leiter System, 3 Aussenleiter und der PEN kommen in das Gebäude. PE vom Gebäude und der PE vom Netz sind miteinander verbunden.

TN mains Mains system as 4 or 5 conductor mains; 3 external conductors and PEN are installed within thebuilding, PE from the building and the PE from the mains are connected.

TT mains Mains system with 4 conductors. Three external conductors and the neutral conductor are instal-led within the building. The PE of the building is not connected to the mains system.

Overvoltage Unwanted continuous or short difference in potential between conductors, or between conductorand earth, which causes interference or destruction.

Overvoltage protection Circuit/wiring of an electric circuit to limit the output voltage.

Overvoltage protection installation Devices and installations included in a system for purposes of overvoltage protection, includingthe leads that form part of such equipment.

Overvoltage protection device Device with at least one non-linear module for limiting transient overvoltages and dischargingsurge currents.

Overvoltage protection classes Classification of electrical equipment according to its voltage strength with reference to thenominal voltage. EN 50178.

Non-symmetrical interference voltage Voltage between conductor and reference potential (earth).

Varistor Voltage-dependent metal oxide resistance; resistance decreases with increasing voltage.

Back-up fuse Max. fuse to be provided depending on connection cross-section and/or longitudinal decoupling.


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Tools

Movement of the blades

Cutting can be categorised based on the method used. Thereare basically two cutting methods:

• squeezing cut,

• pulling cut.

In the squeezing cut, the cutting movement is perpendicularbetween the tool and the work piece. In the pulling cut, thecutting movement is diagonal to the tool.

Position of the blades

In position 1, the blades act directly and along the whole length,requiring considerable force.

In position 2, the blades cross as in a pair of scissors; the cut is therefore “offset” in time and requires less force.

According to DIN 8588, experts differentiate between shearcutting, wedge cutting, tearing and breaking.

Shear cutting is used especially for cutting cables, leads andconductors. Cutting tools with cross blades should perform apulling cut without any play.

One prime quality feature makes professional cutting toolsstand out from the rest: the shape of the blades correspondsto, and is optimised for, the specific intended use. The manualforce required for cutting is relatively small, so that the cuttingtool can be used with just one hand.

Another quality feature is cutting sharpness, i.e. the cuttingangle and presence of a facet. A facet produces a specificslight increase in the cutting angle, increasing the service life of the blade and the cutting sharpness.

Tools by Weidemüller fulfil all the requirements made ofprofessional cutting tools.

Weidmüller uses the term “cutting” to refer to the severing ofcables, leads and conductors made of copper or aluminiumwith a tool specially designed for this purpose.

The requirement for all cutting tools is to perform a straight cutwithout deforming the conductor.

Conductor sheared off

Clean cut

Conductor pulled out Squeezed cable

Insulation

Conductor

An “unclean” cut may look like this:

Squeezing cut Pulling cut

Position 1 Position 2

Cutting

upperedge

loweredge


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Tools

Stripping

Stripping refers to the cutting and removal of insulation.

Compliance with the stripping size must be guaranteed. Neitherthe conductor nor the remaining insulation must be damaged.

DIN IEC 352 part 2 (previously DIN IEC 48/290) refers tostripping faults which must be avoided:

To avoid these faults, it is important for the stripping tool to beadjusted to the insulation and to the cross-section of theconductor.

Cable knives (penknives) should certainly not be used, becausethe stripping quality then depends on the manual skills of theuser – and even when the user is highly skilled, it is not possiblyto achieve uniform high quality.

Preference should be given to manual tools which adjustautomatically to the cross- section of the conductor. They donot cause any damage to the conductor during stripping, andprevent all the above-mentioned stripping faults.

stripax® stripping tools guarantee work of constant anduniformly high quality which complies with the DIN regulations.The tools are rated for standard PVC insulation. Any PVCinsulation thicknesses deviating from the norm are adjustedmanually. The conductor stopper and integrated wire cutterallow for highly versatile use of the tools.

Special insulation such as Teflon, silicone and Kapton requirespecial stripping tools. They strip the conductor using punchblades.

Correctly stripped conductor

Possible stripping faults:

Insulation has not been cut properly

Individual wires have been damaged or cut off by the stripping tool

Insulation remnants are still on the stripped conductor

Individual wires have been twisted too hard afterwards

The conductor insulation has been damaged by the stripping tool

Individual wires are no longer twisted


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Tools

Faulty crimping connections with wrong combinations ofconductor and wire end ferrule:

It is not possible for a tool to work reliably with every possiblecombination of conductors and crimping material.

It is possible that the standard requirements for the crimpedarticle may not be met, although both conductor and crimpingmaterial comply with the relevant standards when consideredindividually. The individual production tolerances of conductorsand crimping materials do not allow every conductor to becombined with every contact.

The combination of conductors, crimping material and crimpingtool must be coordinated: this is all the more difficult to achievegiven the diversity of products on the market.

Therefore, the material must be defined and the crimping resulttested, ensuring that both the test and (later on) the tool satisfythe same conditions.

Faults occurring during crimping:

• Cracks along the edges and punch impressions• Splitting of the wire end ferrules• Asymmetrical crimping shape• Extreme burrs formed along the edges• Ferrule not filled by conductor• Single conductors pushed back, protruding from the collar• Single conductors squeezed off• Plastic collar damaged by the crimping punch• Conductor insulation not pushed into the plastic collar• Wire end ferrule bent longitudinally after crimping

Note:

The ferrule must not split open after it has been connected inany Weidmüller terminal corresponding to the conductor cross-section (with tightening torques acc. to IEC 60947-1)

Cracking at the indentations ofthe crimping punch

Single conductor squeezed off

Single conductor pushed back

Cracking at the side edgingsSplitting of the side edges

Asymmetrical crimping shape

One-sided burr formation

Asymmetrical crimping shape

One-sided burr formation

0.5 mm2 0.75 mm2 1.0 mm2 1.5 mm2 2.5 mm2 4.0 mm2 For cross-sections of 6 … 50 mm2, the crimpingshape is about the same.

Front view:

Crimping wire end ferrules

Optimum crimp of different cross-sections to serve as aquality template

Examples of the visual appraisal of a crimp connection withmanual and automatic crimping tools by Weidmüller:

The conductor insulation must be pushed into the plastic collar.The ferrule pipe must be completely filled by the conductor.Depending on the cross-section, the conductor shouldprotrude approx. 0 … 0.5 mm from the ferrule pipe.

Cross-section diagram: 0…0.5


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