INTERNATIONAL IEC

STANDARD 60694
Edition 2.2
2002-01

Edit ion 2:1996 consol idated w ith amendments 1 :2000 and 2:2001

Common specifications for high-voltage

switchgear and controlgear standards

This Eng/ish-language version is derived from the original

bilingua/ publication by leaving out ali French-language
pages. Missing page numbers correspond to the French-
language pages.

Reference numbe r
IEC 60694: 1996+A1 :2000+A2:2001 (E)
Publication numbering
As from 1 J anuary 1997 all lEC publications are issued with a designation in the
60000 series. For example, IEC 34-1 is now referred to as IEC 60034-1.

Conso lidated editions

The IEC is now p ublishing consolidated versions of its publications. For example,
edition numbers 1.0, 1.1 a nd 1.2 refer, respec tively, to the base publication, the base
publication incorporatin g amendment 1 a nd the base publication incorporating
am endments 1 and 2

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thus e nsuring that the content reflects current technology_ lnformation relating to this
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INTERNATIONAL IEC
STANDARD 60694
Edition 2.2
2002-01

Edit ion 2:1996 consolidated with amendments 1 :2000 and 2:2001

Common specifications for high-voltage

switchgear and controlgear standards

., IEC 2002 Copyright - ali rights reserved

No part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical,
including photocopying and microfilm, without permission in writing from the publisher.

lnternational Electrotechnical Commission, 3, ruede Varembé, PO Box 131, CH-1211 Geneva 20, Switzer1and
Telephone: +41 22 9 19 02 11 Telefax: +41 22 919 03 00 E-mail: inmail@iec.ch Web: www.iec.ch

XE
111 Commission E lectrotechnique lnternationale PRICE CODE
lnternational Electrotechnica l Commission
Me)KJ:lyHapo,QHllR 311e1rrpoTCXNl1'tC(.ll;,!UI KOMHttHR
For price, see CUflent catalogue
60694 © IEC:1996+A1:2000+A2:2001 - 3-

CONTE NTS

FOREWORD. ...... 9

General .. . 13
1.1 Scope ...... ..... 13
1.2 Normative references . ... 13
2 Normal and special service condit ions .. ..23
2.1 Normal service conditions . 25
2.2 Special service conditions . 27
3 Definitions ........ ...... 29
3.1 General terms .............. ....... .. 29
3.2 Assemblies of sw itchgear and controlgear. . 33
3.3 Parts of assemblies ... . ...... 35
3.4 Switching devices ...... ..... 35
3.5 Parts of sw itchgear and controlgear .35
3.6 Operation ....... 45
3. 7 Characteristic quantities ........ . 51
3.8 lndex of definitions .51
4 Ratings ..... .......... ......................... . . 55
4.1 Rated voltage (U,) .... . .55
4.2 Rated insulation level .... 57
4.3 Rated frequency (f,) ....... 65
4.4 Rated normal curren! and temperature rise ... .... 65
4.5 Rated short-time w ithstand curren! Uk) ................ 71
4.6 Rated peak withstand curren! (/p) ...... 7 1
4.7 Rated duration of short circuit (tk) ..... 7 1
4.8 Rated supply voltage of closing and opening devices and of auxiliary
and control circuits (Ua) ... .. 71
4.9 Rated supply frequency of closing and opening devices and of auxiliary circuits.. . 75
4.1 O Rated pressure of compressed gas supply for insulation and/or operation ... . 75
5 Design and construction ................................................... .. 75
5.1 Requirements for liquids in switchgear and controlgear . 75
5.2 Requirements for gases in switchgear and controlgear ... 77
5.3 Earthing of switchgear and cont rolgea r ......... . .77
5.4 Auxiliary and control equipment. ..... ..77
5.5 Dependen! pow er operation ... . . 99
5.6 Stored energy operation ........ . .... 101
5. 7 lndependent manual operation .... 103
5.8 Operation of releases .... 103
5.9 Low - and high-pressure interlocking and monitoring devices ...... . . .. 103
5.1 O Nameplates ... 105
5.11 lnterlocking devices ..... 107
5.12 Position indication ..... 107
5.1 3 Degrees of protection by enclosures .. . 107
5.14 Creepage distances. . .... 111
60694 © IEC:1996+A1:2000+A2:2001 - 5-

5.15 Gas and vacuum tight ness . ... 111

5.16 Liquid t ightness .... .......... ............. . .... 113
5.17 Flammability ..... 113
5.18 Electromagnetic compatibility (EMC ) ..... 115
6 Type tests .. 115
6.1 General ... . ........................ . ... 115
6.2 Dielectric t ests .. . .. .. ................ . .. 119
6.3 Rad io interference voltage (r.i.v.) test .................. . .. 133
6.4 Measurement of !he resistance of c ircuits ............. . .... 137
6.5 Temperature-rise tests .... . .... 139
6.6 Short-time withstand cu rren! and peak w ithstand curren! tests ············ 145
6. 7 Verification of !he protection . . 149
6.8 Tightness tests ... 151
6.9 Electromagnetic compatibility tests ( EMC) ..... 155
6.10 Additional tests on auxiliary and control circuits .............. 163
7 Routine tests .... . .... 171
7.1 Dielect ric test on !he main circuit.. ..... ................. 173
7.2 Tests on auxiliary and control circuits .... . .... 173
7.3 Measurement of !he resistance of !he main circuit ... .... 175
7.4 Tightness test ..... 175
7.5 Design and visual checks .... . .... 177
8 Guide to !he selection of sw itchgear and controlgear .. ..... 177
9 lnformation to be giv en w ith enquiries , tenders and orders . .... 177
1O Rules for transport, storage , installation, operation and maintenance . .... 177
10.1 Conditions during transport, storage and installation ................ . .... 179
10.2 lnstallation.. .......... . .... 179
10.3 Operation ..... 181
10.4 Maintenance ......... ... 181
11 Safety ..... 187
11. 1 Electrical aspects .. . .... 187
11 .2 Mechanical aspects ..... 187
11.3 Thermal aspects ... . . .... 187
11 .4 Operation aspects ..... ... . .... 187

Annex A (normative) ldentification of test specimens ..... 195

Annex B (normative) Determination of !he equivalen! r.m.s . value of a short-time
curren! during a short circuit of a given duration ..... . .... 199
Annex C (normative) Method for !he w eatherproofing test for outdoor sw itchgear
and controlgear. . . 201
Annex D (informative) lnformation about insulation levels and tests ..... 207
Annex E (informative) Tightness (information , example and gu idance) ...... ....................... 213
Annex F (informative) Dielectric testing of self-protected switchgear and controlgear ....... 217
Annex G (informative ) Bibliography. .. ................. ..223
Annex H (informative) Electromagnetic compatibility site measurements .......... ................ 225
60694 © IEC:1996+A1:2000+A2:2001 -7-

Figure 1 - Altitude correction factor (see 2.2.1 ) .... ... 189

Figure 2 - Diagram of connections of a th ree-pole switching device (see 6.2.5.1 ) . 191
Figure 3 - Diagram of a test circuit for the rad io interference voltage test of
sw itching devices (see 6.3) ..... 193
Figure 4 - Examples of classes of contacts .87
Figure 5 - Example of secondary system in medium voltage cubicle .97
Figure 6 - Example of secondary system of air insulated circuit-breaker
w ith single mechanism ................. ............................. .......... ......... . .. 97
Figure 7 - Example of secondary system of air insulated circuit-breaker
w ith separate control cubic le ........ ... ................. . ...... 99
Figure 8 - Example of secondary system for GIS bay ... 99
Figure 9 - Example of choice of EMC severity class ..... . . .... 115
Figure B.1 - Determination of short-time curren! ..... 199
Figure C .1 - Arrangement for weatherproofing test ......... 203
Figure C .2 - Nozzle for w eatherproofing test ... 205
Figure E.1 - Example of a tightness coordination chart, TC ,
for closed pressure systems ........ ... ................. ..................... ................... ..... 213
Figure E.2 - Sensitivity and applicability of different leak detection methods
for tightness tests ...... .......... ........ ............................ .... . .... 215
Figure F.1 - Examples of impulse vo ltage shapes w ith incorporated
voltage-limiting devices ..... 221

Table 1a - Rated insulation leve Is for rated voltages of range 1, series 1... . 59
Table 1b - Rated insulation leveIs for rated voltages of range 1, series 11
(used in North America). . 61
Table 2a - Rated insulation levels for rated voltages of range 11 ...... 63
Table 2b - Additional rated insulation levels in North America for range 11 ...... 65
Table 3 - Limits of temperature and temperature rise for various parts, materials
and dielectrics of high-voltage switchgear and controlgear . 67
Tables 4 and 5 (withdraw n)
Table 6 - Degrees of protection .... 109
Table 7 - Application factors for creepage distances .... 111
Table 8 - Example of grouping of type tests ..... 117
Table 9 - Test conditions in general case ......... . .... 125
Table 1O - Power-frequency test conditions for longitudinal insu lation ............ . .. 125
Table 11 - Impulse test conditions for long itudinal insulation .. ... 127
Table 12 - Permissible temporary leakage rates for gas systems ..... 151
Table 13 (withdraw n)
Table 14 - Direct curren! voltage ....... 73
Table 15 - Alternating curren! voltage ...... 73
Table 16 - Auxiliary contacts classes .. ....... 87
Table 17 - Application of voltage at the fast transient/burst test.. .... .. 159
Table 18 - Application of voltage at the damped oscillatory wave test .. 161
Table 19 - Assessment criteria for t ransient disturbance immunity tests ... .. 163
60694 © IEC:1996+A1:2000+A2:200 1 - 9-

INTERNATI ONA L ELECTROTE CHNICAL COMM ISSION

COMMON SPECIFICATIONS FOR HIGH-VOL TAGE

SWITCHGEAR ANO CONTROLGEAR STANDARDS

FOREWORD
1) The IEC (lnternational Electrotechnical Commission) is a worldwide organization for standardization comprising
all nationa1 electrotechnical committees (IEC National Committees). The object of the IEC is to promete
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, the IEC publishes lnternational Standards. Their preparation is
entrusted to technical committees; any IEC National Committee interested in the subject dealt with may
participate in this preparatory work. lnternational, governmental and non-governmental organizations liaising
with the IEC also participate in this preparation. The IEC collaborates closely with the lnternational
Organ ization for Standardization (ISO) in accordance with cond itions determined by agreement between the
two organizations.
2) The forma l decisions or agreements of the IEC on technical matters express, as nearly as possible, an
international consensus of opinion on the re levant subjects since each technical committee has representation
from all interested National Committees.
3) The documents produced have the form of recommendations for international use a nd are published in the form
of standards, technical speci fications, technical reports or guides and they are accepted by the National
Committees in that sense.
4) In order to p romote international unification , IEC National Comm ittees undertake to apply IEC lnternational
Standards transparently to the maximum exten t possible in their national and regional stand ards. Any
divergence between the IEC Standard and the corresponding national or reg ional s tandard shall be clearly
indicated in the latter.
5) The IEC provides no marking procedure to indicate its approval and c annot be rendered responsible for any
equipment declared to be in conformity with one of its standards.
6) A ttention is drawn to the possibility that sorne of the elements of this lnternational Standard may be the subject
of patent rights. The IEC shall not be held responsible fo r ide ntifying any or all such patent rights.

lnternational St andard IEC 60694 has been prepared by subcommittee 17A: High-voltage
sw itchgear and controlgear, and subcommittee 17C: High-voltage enclosed switchgear and
controlgear, of IEC technical committee 17: Sw itchgear and controlgear.

This consolidated version of IEC 60694 is based on the second edition (1 996) [documents
17A/458/FDIS and 17A/479/RVD, its amendment 1 (2000) [documents 17A/579/FDIS and
17A/588/RVD), its corrigendum of January 2001 , its amendment 2 (2001 ) [documents
17A/599/FDIS and 17A/609/RVD] and its corrigendum of December 2001.

11 bears the edition number 2.2.

A vert ical line in the margin shows w here the base publicat ion has been modified by
amendment 1, amendment 2 and the corrigenda.

Annexes A , B and C form an integral par! of t his standard.

Annexes D to H are for information only.

The follow ing differences exist in sorne countries:

6.2.11 The required test voltage for disconnectors and sw itch-disconnectors of all rated
voltages is 100 % of the tabulated voltage in columns 3 of tables 1a or 1b and 2a or 2b
(Canada, France , ltaly).
60694 © IEC:1996+A1:2000+A2:2001 - 11 -

The committee has dec ided that the contents of the base publication and its amendments will
remain unchanged until 2007. At this date, the publication will be

reconfirmed ;
withdraw n;
replaced by a revised edition, or
amended.
60694 © IEC:1996+A1:2000+A2:200 1 - 13 -

COMMON SPECIFICATIONS FOR HIGH-VOL TAGE

SWITCHGEAR ANO CONTROLGEAR STANDARDS

General

1.1 Scope

This lnternational Standard applies to a.c. sw itchgear and controlgear, designed for indoor
and outdoor installation and for operation at service frequencies up to and including 60 Hz on
systems having voltages above 1 000 V.

This standard applies to all high-voltage switchgear and controlgear except as otherwise
specified in the relevan! IEC standards for the part icular type of sw itchgear and controlgear.

1.2 Normative references

The following normative documents contain provis ions w hich, through reference in this text,
constitute provisions of t his lnternational Standard. At the time of publication, the editions
indicated w ere valid. AII normative documents are subj ect to revis ion, and parties to
agreements based on this lnternat ional Standard are encouraged to investigate the possibi lity
of applying the most recent editions of the normative documents indicated below. Members of
IEC and ISO maintain registers of currently valid lnternationa l Standards.

IEC 60034-1: 1996, Rotating electrical machines - Part 1: Rating and performance

IEC 60038: 1983 , IEC standard voltages

IEC 60050( 131 ): 1978, Interna/ion al Electrotechnical Vocabulary (IE V) - Chapter 131: Electric
and magnetic circuits

IEC 60050( 151 ): 1978, lnternational Electrotechnica/ Vocabu/ary (IE V) - Chapter 151: Electrica/
and magnetic devices

IEC 60050( 191 ): 1990, lnternational Electrotechnical Vocabulary (IE V) - Chapter 191: Depen-
dability and quality of service

IEC 60050(301 ): 1983, lnternational Electrotechnical Vocabulary (IE V) - Chapter 301: General
terms on measurements in electricity

IEC 60050-351: 1998, lnternational Electrotechnical Vocabulary (IE V) - Part 351: Automatic
control

IEC 60050(441 ): 1984, lntemational Electrotechnical Vocabulary (IEV) - Chapter 441: Switchgear,
controlgear and fuses

IEC 60050(446):1983, lnternational Electrotechnical Vocabulary (IEV) - Chapter 446: Electrical

relays

IEC 60050(581 ): 1978, lnternational Electrotechnical Vocabulary (IE V) - Chapter 581: Electro-
mechanical components for e /ectronic equipment
60694 © IEC:1996+A1:2000+A2:2001 - 15 -

IEC 60050(604 ): 1987, lnternational Electrotechnical Vocabulary (IE V) - Chapter 604: Generation,
transmission and distribution of electricity - Operation

IEC 60050(811 ): 1991, lnternational Electrotechnical Vocabulary (IE V) - Chapter 811: Electric
trae/ion

IEC 60050(826): 1982, lnternational Electrotechnical Vocabulary (IEV) - Chapter 826: Electrical
installations of buildings

IEC 60051 -2: 1984, Direct acting indicating analogue electrical measuring instruments and
their accessories - Par/ 2: Special requirements for ammeters and voltmeters

IEC 60051 -4: 1984, Direct acting indicating analogue electrical measuring instruments and
their accessories - Par/ 4: Special requirements for frequency meters

IEC 60051 - 5: 1985, Direct acting indicating analogue electrical measuring instruments and
their accessories - Part 5: Special requirements for phase m eters, power factor meters and
synchroscopes

IEC 60056: 1987 , High-voltage alternating-current circuit-breakers

IEC 60059: 1938, IEC standard curren/ ratings

IEC 60060-1 :1 989, High-voltage test techniques - Par/ 1: General definitions and test
requirements

IEC 60064: 1993 , Tungsten filament lamps for domestic and similar general Jighting purposes -
Performance requirements

IEC 60068-2 (all parts), Environmental testing - Par/ 2: Tests

IEC 60068-2-1: 1990, Environm ental testing - Par/ 2: Tests. Tests A: Cold

IEC 60068-2-2:1974, Environmental testing - Par/ 2: Tests. Tesis B: Dry heat

IEC 60068-2-3: 1969, Environmental testing - Par/ 2: Tests . Test Ca: Damp heat, steady state

IEC 60068-2-17:1994, Environmental testing - Par/ 2: Tests - Test Q: Sealing

IEC 60068-2-30:1980, Environ mental testing - Par/ 2: Tests. Test Db and guidance: Damp \
heat, cyclic (12 + 12-hour cycle)

IEC 60068-2-63: 1991, Environmental testing - Par/ 2: Tests - Test Eg: lmpact, spring hammer

IEC 60071 - 1: 1993, lnsulation co-ordination - Par/ 1: Definitions, principies and rules

IEC 60071-2: 1996, lnsulation co-ordination - Part 2: Application guide

IEC 60073 :1996 , Basic and safety principies for man-machine interface, m arking and 1
identifica/ion - Coding principies for indica/ion devices and actuators
60694 © IEC:1996+A1:2000+A2:200 1 - 17 -

IEC 60081 :1997, Double-capped f/uorescent lamps - Performance specifications

IEC 60083: 1997, Plugs and socket-outlets for domestic and similar general use standardized
in member countries of IE C

IEC 60085: 1984 , Thermal evaluation and classification of electrical insulation

IEC 60115-4: 1982, Fixed resistors for use in electronic equipment - Part 4: Sectional
specification: Fixed power resistors

IEC 60130 (all parts), Connectors for frequencies below 3 MHz

IEC 60227 (all parts), Polyvinyl chloride insulated cables of rated voltages up to and
including 4501750 V

IEC 60228: 1978, Conductors of insulated cables

IEC 60245 (all parts), Rubber insulated cables - Rated voltages up to and including 4501750 V

IEC 60255-5: 1977, Electrical relays - Part 5: lnsulation tests for electrical relays

IEC 60255-8: 1990, Electrical relays - Part 8: Thermal electrical relays

IEC 60255-21 - 1:1988, Electrical relays - Part 21: Vibra/ion, shock, bump and seismic tests on
measuring relays and protection equipment - Section One: Vibra/ion tests (sinusoidal)

IEC 60255-21 -3:1993, Electrical relays - Part 21: Vibra/ion, shock, bump and seismic tests on
measuring relays and protection equipment - Section 3: Seismic tests

IEC 60255-23:1994, Electrical relays - Part 23: Contact performance

IEC 60269- 1: 1998, Low-voltage fuses - Part 1: General requirements

IEC 60269-2: 1986, Low- voltage fu ses - Part 2: Supplementary requirements for fu ses for use
by authorized persons (fuses mainly for industrial application)

IEC 60269-2-1:1998, Low- voltage fuses - Part 2- 1: Supplementary requirements for fuses for
use by authorized persons (fuses mainly for industrial app/ication) - Sections I to V: Examples
of types of standardized fuses

IEC 60270: 1981, Partía/ discharge measurements

IEC 60296 :1982 , Specification for unused mineral insulating oils for transformers and
switchgear

IEC 60309- 1: 1999, Plugs, socket-outlets and couplers for industrial purposes - Part 1:
General requirements

IEC 60309-2: 1999, Plugs, socket-outlets and couplers for industrial purposes - Part 2:
Dimensional interchangeability requirements for pin and contact-tube accessories

IEC 60326 (all parts), Printed boards

60694 © IEC:1996+A1:2000+A2:2001 - 19 -

IEC 60376: 1971, Specification and acceptance of new sulphur hexafluoride

IEC 60393- 1: 1989, Potentiometers for use in electronic equipment - Part 1: Generic
specification

IEC 60417 (all parts), Graphical symbols for use on equipment

IEC 60445: 1999, Basic and safety principies for man-machine interface, marking and
identifica/ion - Identifica/ion of equipment terminals and of terminations of certain designated
conductors, including general rules for an alphanumeric system

IEC 60480: 1974 , Guide to the checking of sulphur hexafluoride (SF6) taken from electrical
equipment

IEC 60485: 1974 , Digital electronic d.c. voltmeters and d.c. electronic analogue-to-digital
converters

IEC 60502- 1:1997, Power cables with extruded insulation and their accessories for rated
voltag es from 1 kV (Um = 1, 2 kV) up to 30 kV (Um = 36 kV) - Part 1: Cables for rated voltages
of 1 kV (Um = 1, 2 kV) and 3 kV (Um = 3, 6 kV)

IEC 60507: 1991, Artificial poi/u/ion tests on high-voltage insulators to be u sed on a.c.
systems

IEC 60512-2:1985, Electromechanical components for electronic equipment; basic testing

procedures and measuring methods - Part 2: General examina/ion, electrical continuity and
contact resistance tests, insulation tests and voltage stress tests

IEC 60529: 1989, Degrees of protection provided by enclosures (IP code)

IEC 60617 , Graphical symbols for diagrams

IEC 60669- 1: 1998, Switches for household and s imilar fixed-electrical installations - Par/ 1:
General requirements

IEC 60721 , C/assification of environmental conditions

IEC 60730-2-9: 1992, Automatic electrical controls for household and similar use - Par/ 2:
Particular requirements for temperature sensing controls

IEC 60730-2-13:1995, Automatic electrical controls for household and similar use - Part 2:
Particular requirements for humidity sensing controls

IEC 60815: 1986, Guide for the se lection of insulators in respect of polluted conditions

IEC 60816: 1984 , Guide on methods of measurement of short-duration transients on low-

voltage power and signa/ lines
60694 © IEC:1996+A1:2000+A2:200 1 - 21 -

IEC 60947-2: 1995, Low-voltage switchgear and controlgear - Part 2: Circuit-breakers

IEC 60947- 3: 1999, Low-voltage switchgear and controlgear - Part 3: Switches, disconnectors,
switch-disconnectors and fuse-combination units

IEC 60947-4-1:1990, Low- voltage switchgear and controlgear - Part 4: Contactors and motor-
starters - Section One: Electromechanical contactors and motor-starters

IEC 60947-4-2:1995, Low- voltage switchgear and controlgear - Part 4: Contactors and motor-
starters - Section 2: AC semiconductor motor controllers and starters

IEC 60947- 5-1: 1997, Low- vo/tage switchgear and controlgear - Part 5: Control circuit de vices
and switching elements - Section One: Electromechanical control circuit devices

IEC 60947-7-1: 1989, Low- voltage switchgear and controlgear - Part 7: Ancillary equipment -
Section One: Terminal blocks for copper conductors

IEC 60947-7-2:1995, Low- voltage switchgear and controlgear - Part 7: Ancillary equipment -
Section 2: Protective conductor terminal blocks for copper conductors

IEC 61000-4-1: 1992, Electromagnetic compatibility (EMC) - Part 4: Testing and measurement
techniques - Section 1: Overview of immunity tests - Basic EMC publication

IEC 61000-4-4 :1995, Electromagnetic compatibility (EMC) - Part 4: Testing and measurement
techniques - Section 4: Electrical fast transientlburst immunity test - Basic EMC Publication

IEC 61000-4-12:1995, Electromagnetic compatibility (EMC) - Part 4: Testing and measure-

ment techniques - Section 12: Oscillatory waves immunity test - Basic EMC Publication

IEC 61000-4-17:1999, Electromagnetic compatibility (EMC) - Part 4- 17: Testing and measure-
ment techniques - Ripple on d.c. input power port immunity test

IEC 61000-4-29:- , Electromagnetic compatibility (EMC) Part 4- 29: Testing and

measurement techniques - Voltage dips, short interruptions and voltage variations on d.c.
input power ports, immunity tests 1 >

IEC 61000-5 (all parts), Electromagnetic compatibility (EMC) - Part 5: lnstallation and
mitiga/ion guidelines

IEC 61000-5-1: 1996, Electromagnetic compatibility (EMC) - Part 5: lnstallation and mitigation
guidelines - Section 1: General considerations - Basic EMC publication

IEC 61000-5-2:1997, Electromagnetic compatibility (EMC) - Part 5: Insta/la/ion and mitigation

guidelines - Section 2: Earthing and cabling

IEC 61000-6-5:- , Electromagnetic compatibility (EMC) - Part 6-5: Generic standards - lmmunity
for power station and substation environments 1)

1) To be published
60694 © IEC:1996+A1:2000+A2:2001 - 23 -

IEC 61020-4: 1991 , Electromechanical switch es for use in electronic equipment - Part 4: 1
Sectional specification for le ver (toggle) switches

IEC 61166:1993 , High-voltage alternating curren/ circuit-breakers - Guide for seismic

qualification of high-voltage alternating current circuit-breakers

IEC 61180-1:1992, High- voltage test techniques for low-voltage equipment - Part 1: Defi-
nitions, test and procedure requirements

IEC 61634:1995 , High-voltage s witchgear and controlgear - Use and handling of sulphur
hexafluoride (SF6) in high-voltage switchgear and controlgear

IEC 61810 (all parts), Electrom echanical non-specified time a/1-or-nothing relays

IEC 61810-1:1998, Electromechanica/ non-specified time a/1-or-nothing relays - Part 1:

General requirements

IEC 61810-7:1997, Electromechanical a/1-or-nothing relays - Part 7: Tests and measurement

procedures

C ISPR 11: 1990, Limits and m ethods of measurement of electromagnetic disturbance

characteristics of industrial, scientific and medica/ (ISM) radio-frequency equipment

CISPR 16- 1:1993, Specification for radio disturbance and immunity measuring apparatus and
methods - Part 1: Radio disturbance and immunity measuring apparatus

C ISPR 18-2:1986, Radio interference c haracteristics of overhead power fines and high-
voltage equipment - Part 2: Methods of measurement and p rocedure for determining limits
Amendment 1 ( 1993)

Other lnternational Standards are referred to for information in th is standard. They are listed
in annex G.

2 Normal and special service conditions

Unless otherwise specified, high-voltage switchgear and controlgea r, including !he operating
devices and the auxiliary equipment w hich form an int egral part of them , are intended to be
used in accordance with their rated characteristics and the normal service conditions listed
in 2.1.

lf the actual service conditions differ from these normal service conditions, high-voltage
sw itchgear and controlgear and associated operating devices and auxiliary equipment shall
be des ign ed to comply with any specia l service conditions required by the user, or appropriate
arrangements shall be made (see 2.2) .
NOTE 1 Appropriate action should also be taken to ensure proper operation under such conditions of other
components, such as relays
NOTE 2 Detailed information concerning classification of environmental conditions is given i n IEC 60721 -3-3
(indoor) and I EC 60721 - 3-4 (outdoor)
60694 © IEC:1996+A1:2000+A2:2001 - 25 -

2.1 Normal service conditions

2.1.1 lndoor switchgear and controlgear

a) The ambient air temperature does not exceed 40 º C and its a verage value, measured over
a period of 24 h, does not exceed 35 º C.
The mínimum am bient air temperature is - 5 º C for c lass "m inus 5 indoor", - 15 º C for c lass
"minus 15 indoor" and -25 º C for c lass "minus 25 indoor".
b) The influen ce of solar radiation may be neglected.
c) The altitude does not exceed 1 000 m.
d) The ambient air is not significantly pollut ed by dust, smoke, corrosive and/o r flammable
gases , vapours or salt.
e) The conditions of humidity a re as follows:
the a verage value of t he relative hum idity, measured over a period of 24 h, does not
exceed 95 %;
the a verage value of the water vapour pressure , over a period of 24 h, does not
exceed 2 ,2 kPa;
the average val ue of the re lative hum idity, over a period of one month , does not
exceed 90 %;
the average value of the w ater vapour pressure, over a period of one month, does not
exceed 1,8 kPa.

For these condit ions, condensation may occasionally occur .

NOTE 1 Condensation can be expected where sudden temperature changes occur in periods of high
humidity
NOTE 2 To withstand the effects of high humidity and condensation, such as breakdown of insulation or
corrosion of metallic parts, switchgear designed far such conditions a nd tested accordingly should be used.
NOTE 3 Condensation may be prevented by special design of the building or housing, by suitable ventilation
and heating of the station or by the use of dehumidifying equipment

f) Vibration due to cau ses externa! t o the switchgear and controlgear or eart h tremors are
negligible.
g) lnduced electromagnetic disturbances at interfaces of the secondary s ystem , as a result of
switching in the high-voltage system , do not e xceed 1,6 kV common mode for normal EMC
severity class, and 0 ,8 kV common mode f or reduced EMC severity class.
NOTE 4 The maximum induced voltage values may be exceeded at interfaces to instrument transformers.
Refer to instrument transformer standards for adequate performances of these devices.

2.1.2 Outdoor switchgear and controlgear

a) The ambient air temperatu re does not exceed 40 º C and it s a verage value, measured over
a period of 24 h, does not exceed 35 º C .
The mínimum ambient air temperature is - 1 O º C f er class "minus 10 outdoor", -25 º C for
class "m inus 25 outdoor" and -40 ºC f er class "m inus 4 0 outdoor".
Rapid temperature changes s hould be tak en into account.
b) Solar rad iat ion up to a level of 1 0 00 W/m 2 (on a clear day at noon) should be considered.
NOTE 1 Under certain conditions of solar radiation appropriate measures, e .g. roofing , forced ventilation, etc.
may be necessary, ar derating may be used, in order not to exceed the specified temperature rises
NOTE 2 Details of global solar radiation are given in IEC 60721~2~4.
60694 © IEC:1996+A1:2000+A2:2001 - 27 -

c) The altitude does not exceed 1 000 m.

d) The ambient air may be polluted b y dust, smoke, corrosive gas , vapours or sal!. The
pollution does not exceed the pollution level 11 - Medium according to t able 1 of
IEC 60815.
e) The ice coating does not exceed 1 mm for class 1, 10 mm for class 10 and 20 mm for
class 20.
f) The wind speed does not exceed 34 m/s (corresponding to 700 Pa on cylindrical
surfaces).
NOTE 3 Characteristics of wind are described in IEC 60721 - 2-2.

g) Account should be taken of the presence of condensation or precipitations.

NOT E 4 Characteri stics of precipitation are defined in IEC 60721 -2-2

h) Vibration due to causes externa! to the switchgear and controlgear orto earth tremors are
negligible.
i) lnduced electromagnetic disturbances at interfaces of the secondary system, as a result of
switching in the high-voltage system , do not exceed 1,6 kV common mode for normal EMC
severity class, and 0 ,8 kV common mode for reduced EMC severity class.
NOTE 5 The maximum induced volta ge values may be exceeded at interfaces to instrument transformers.
Refer to instrument transformer standards far adequate performances of these devices.

2.2 Special service conditions

When high-voltage switc hgear and controlgear may be used under conditions different from
t he normal service conditions given in 2.1, the user's requirements should refer to
standardized steps as follows.

2.2.1 Altitude

For installation at an altitude higher than 1 000 m , the insulation level of externa! insulation
under the standardized reference atmospheric conditions shall be determined by multiplying
the insulation withstand voltages required al the service location by a factor Ka in accordance
with figure 1.
NOTE 1 Far interna! insulation, the dielectric characteristics are identical al any altitude and no special
precautions need to be taken. Far externa! and interna! insulation, see IEC 60071 -2 .
NOTE 2 Far low-voltage auxiliary and control equipment, no special precautions need to be taken if the altitude is
lower than 2 000 m. For higher altitude, see IEC 60664- 1.

2.2.2 Pollution

For installation in polluted ambient air, a pollution level 11 1 - Heavy, or IV - Very heavy of
IEC 60815 should be specified .

2.2.3 Temperature and humidity

For installation in a place w here the ambient temperature can be significantly outside the
normal service condition range stated in 2.1 , the preferred ranges of mínimum and maximum
temperature to be specified should be:

-50 ºC and +40 ºC for very cold climates;

-5 ºC and +50 ºC for very hot climates.

In certain regions with frequent occurrence of w arm humid winds , sudden changes of
temperature may occur resulting in condensation even indoors.

In tropical indoor conditions, the average value of relative humidity measured during a period
of 24 h can be 98 %.
60694 © IEC:1996+A1:2000+A2:2001 - 29 -

2.2.4 Vibrations

For installations w here earthquakes are likely to occur, severity level in accordance w ith
IEC 61166 should be specified by the user.

2.2.5 Other parameters

When special environmental conditions prevail at the location w here switchgear and
controlgear is to be put in servic e, they shou ld be specified by the user by reference to
IEC 60721 .

3 Definitions

For the purpose of this lnternational Standard , the definitions in IEC 60050(151 );
IEC 60050( 191 ); IEC 60050(44 1); IEC 60050(604) and IEC 60050(826) apply.

Sorne of them are recalled hereunder for eas ier use.

The definitions given below are also applicable. They are classified in accordance w ith
IEC 60050(441 ). The definitions of IEC 60050(441) are not repeated but reference is made to
their specific sub-clause number. References from other t han IEC 60050(441) are classified
so as to be aligned w ith the classification used in lnternational Electrotechnical Vocabulary
IEC 60050(441 ).

3.1 General terms

3.1.1
switchgear and controlgear
[IEV 441-11-01]

3.1.2
externa! insulation
the distances in atmosphere and the surfaces in contact with open air of solid ins ulation of the
equipment w hich are subject to dielectric stresses and to the effects of atmospheric and other
externa( conditions such as pollution, humidity, vermin etc.
[IEV 604-03-02]

3.1.3
IP code
a coding system to indicate the degrees of protection provided by an enclosure against
access to hazardous parts , ingress of solid foreign objects, ingress of w ater and to give
additional information in connection with such protection [3.4 of IEC 60529]

3.1.4
protection provided by an enclosure against access to hazardous parts
the protection of persons against:
- contact with hazardous mechanical parts;
- contact with hazardous low-voltage live parts;
- approach to hazardous high-voltage live parts below adequate clearance inside an
enclosure [3.6 of IEC 60529]

3.1.5
maintenance
the combination of all technical and administrative actions , including supervision actions, intended
to retain an item in, or restore it to, a state in w hich it can perform a required function
[IEV 191-07-01]
60694 © IEC:1996+A1:2000+A2:2001 - 31 -

3.1.6
scheduled maintenance
the prev entive maintenance carried out in accordance w ith an established time schedule
[IEV 191-07-10]

3.1.7
inspection
periodic visual investigation of the p rincipal features of the switchgear and controlgear in
service w ithout dismantling. This inv estigation is generally directed toward pressures and/or
levels of fluids , tightness , position of relays, pollution of insulating parts, but actions such as
lubricating, cleaning, w ashing, etc . w h ich can be carried out w ith the sw itchgear and
controlgear in service are also included
NOTE Observations resultin g from inspection can lead to the decision to carry out overhaul.

3.1.8
diagnostic tests
comparative tests of the characteristic parameters of switchgear and controlgear to verif y that
it performs its functions , by measuring ene o r more of these parameters
NOTE The result from d iagnostic te sts ca n lead to the decisi on to c arry out overha ul

3.1.9
examination
inspection w ith the addition of pa rtial dismantling , as required , supplemented by means such
as measurements and non-destructive tests in order to reliably eva luate the condition of the
sw itchgear and controlgear

3.1.10
overhaul
work done w ith the objective of repairing or replacing pa rts w hich a re found to be out of
tolerance by inspection, test, examination, or as required by manufacturer's maintenance
manual, in order to restore the componen! and/ or the sw itchgear and controlgear to an
acceptable condit ion

3.1.11
down time
the time interv al during w hich an item is in a dow n state
[IEV 191-09-08]

3.1.12
failure
the termination of the ability of an item to perform a required function
[IEV 191-04-01]
NOTE 1 A fter failure the item has a fault
NOTE 2 "Failure" is an event, as distinguished from "fault", which is a state.
NOTE 3 This concept as defined does not apply to items consisting of software only.

3.1.13
major failure (of switchgear and controlgear)
failure of a sw itchgear and controlgear wh ich causes the cessation of ene or more of its
fundamental functions

A major failure w ill result in an immediate change in the system operating c onditions, e.g. the
backup protective equ ipment w ill be required to remov e the fault, or w ill result in mandatory
removal from service w ithin 30 min fer unscheduled maintenance
60694 © IEC:1996+A1:2000+A2:2001 - 33 -

3.1.14
minor failure (of switchgear and controlgear)
any failure of a constructional element or a sub-assembly w hich does not cause a major
failure of the switchgear and controlgear

3.1.15
defect
an imperfection in the state of an item (or inherent w eakness ) which can result in one or more
failures of the item itself, or of another item under the specific service or environmental or
maintenance conditions, for a stated period of time

3.1.16
ambient air temperature
[IEV 441-11-13]

3.1.17
servicing leve!
ground level or fixed permanent f loor level from w hich an authorized person can operate a
device

3.1.18
non-exposed type
type of compone ni of w hich no live part can readily be touched

3.1.19
monitoring
observation of the operation of a system or part of a system to verify corree! functioning by
detecting incorrect functioning; this being done by measuring one or more variables of the
system and comparing the measured values with the specified values
[IEV 351-18-24 , modified]
NOTE Severa! definitions are given far this term in the IEV. They are related to different cases of application.
The reference given above is to be applied in the present case.

3.1.20
supervision
activity, performed either manual ly or automatical ly, intended to observe the state of an item
[IEV 191 -07-26]
NOTE Several definitions are given for this term in the IEV. They are relatad to different cases of application. The
reference given above is to be applied in the present case.

3.2 Assemblies of switchgear and controlgear

3.2.1
self-protected switchgear
sw itchgear and controlgear incorporating integral voltage-limiting devices

3.2.2
test specimen
a test specimen is a complete switchgear and controlgear w hen the poles are mechanically
linked (i.e. one operating mechanism) or when the type tests are mainly three-pole type tests.
lf this is not the case , a test specimen is one pole of the complete switchgear and controlgear.
Where permitted in the relevan! IEC standard , a test specimen may be a representative sub-
assembly
60694 © IEC:1996+A1:2000+A2:2001 - 35 -

3.3 Parts of assemblies

3.3.1
transport unit
a par! of switchgear and controlgear suitable for transportation w ithout being dismantled

3.4 Switching devices

No particular definitions.

3.5 Parts of switchgear and controlgear

3.5.1
enclosure
a part providing protection of equ ipment against certain externa! influences and , in any
direction , protection against direct contact
[IEV 826-03-12]
NOTES This definition taken from IEC 60050(826) needs the following explanations under the scope of this
standard:
Enclosures provide protection of persons or livestock against access to hazardous parts.
2 Barriers, shapes of openings or any other means - whether attached to the enclosure or formed by the
enclosed equipment suitable to prevent or limit the penetration of the specified test probes are considered
as a part of the enclosure, except when they can be removed without the use of a key or tool [3. 1 of
IEC 60529)

3.5.2
hazardous part
a part that is hazardous to approach or touch [3.5 of IEC 60529]

3.5.3
contact
[IEV 441-15-05]

3.5.4
auxiliary circuit
[IEV 441-15-04]

3.5.5
control circuit
[IEV 441-15-03]

3.5.6
auxiliary switch
[IEV 441-15-11]

3.5.7
control switch
[IEV 441-14-46]

3.5.8
auxiliary contact
[IEV 441-15-10]

3.5.9
control contact
[IEV 441-15-09]
60694 © IEC:1996+A1:2000+A2:2001 - 37 -

3.5.10
connection {bolted or the equivalent)
tw o or more conductors designed to ensure permanent circuit continuity w hen torced together
by means of screw s, bolts or the equivalen!

3.5.11
position indicating device
[IEV 441-15-25]

3.5.12
monitoring device
device intended to observe automatically the state of an item
[from IEV 191-07-26]

3.5.13
pilot switch
[IEV 441-14-48]

3.5.14
low energy contact
contact des igned to be used in very low energy circuits, e.g. for monitoring or information
technology
NOTE Typical applications are contacts inserted into a load circuit through which flows a current of sorne
milliamperes at a voltage not exceeding 1 O V at the term inals.

3.5.15
cable entry
par! with openings , w h ic h perm it the passage of cables into the enclosure

3.5.16
cover plate
par! of an enclosure which is used for closing an opening and designed to be held in place by
screws or sim ilar means. 11 is not normally removed alter the equipment is pul in service

3.5.17
partition
par! of an assembly separating one compartment from other compartments
[IEV 441-13-06]

3.5.18
actuator
par! of the actuating system to w hich an externa! actuating force is applied
NOTE The actuator may take the form of a handle , knob, push-button, roller, plunger, e tc.
[IEV 441-15-22]

3.5.19
indicating device {of a measuring instrument)
ensemble of components of a measuring instrument intended to indicate the value of the
measured quantity
NOTE By extension, the indicating means ar setting device of any instrument such as a material measure or a
signar generator.
[IEV 301 -07-01]
60694 © IEC:1996+A1:2000+A2:2001 - 39 -

3.5.20
splice
connecting device w ith barrel(s) accommodating electrical conductor(s) with or w ithout
additional provision to accommodate and secure the insulation
[IEV 581-05-11]

3.5.21
terminal
point of an electric circuit, intended for making a connection
[IEV 131-01-02]

3.5.22
terminal block
assembly of terminals in a housing or body of insulating material to facilitate interconnection
between multiple conductors
[IEV 581-06-36]

3.5.23
neutral conductor (symbol N)
conductor connected to the neutral point of a system and capable of contributing to the
transmission of electrical energy
[IEV 826-01-03]

3.5.24
protective conductor (symbol PE)
conductor required by sorne measures for protection against electric shock for electrically
connecting any of the following parts:
- exposed conductive parts;
- extraneous conductive parts;
- main earthing terminal;
- earth electrode;
- earthed point of the source or artific ial neutral
[IEV 826-04-05]

3.5.25
PEN conductor
earthed conductor combining the functions of both protective conductor and neutral conductor
NOTE The acronym PEN results of the combination of both symbols PE for the protective conductor and N for the
neutral conductor.
[IEV 826-04-06]

3.5.26
all-or-nothing relay
electrical relay w hich is intended to be energized by a quantity w hose value is either within its
operative range or effectively zero
[I EV 446-11-02]

3.5.27
thermal electrical relay
dependant-time measuring relay w hich is intended to protect an equipment from electrical
thermal damage by measurement of the curren! flowing in the protected equipment and by a
charactenstic curve simulating its thermal behaviour
[IEV 446-15-16]
60694 © IEC:1996+A1:2000+A2:2001 -41 -

3.5.28
(mechanical) contactar
mechanica l switching device havi ng only one pos ition of rest, operated otherwise than by
hand, capable of making , carrying and breaking currents under normal circuit conditions
including operating overload conditions
NOTE Contactors may be designated according to the method by which the force fo r closing the main contacts is
provided.
[IEV 441-14-33]

3.5.29
starter
combination of all the switch ing means necessary to start and stop a motor in combination
with suitable overload protection
NOTE Starters may be designated according to the method by which the force for closing the main contacts is
provided.
[IEV 441-14-38]

3.5.30
shunt release
release energ ized b y a source of voltage
NOTE The source of voltage may be independent of the voltage of the main circuit.
[IEV 441-16-41]

3.5.31
switch
componen! fitted with an actuator and contacts to make and break a connection
[IEV 581-10-01]

3.5.32
distribution circuit (of buildings)
circuit supplying a distribution board
[IEV 826-05-02]

3.5.33
final circuit (of buildings)
circuit connected directly to curren! using equipment or to socket-outlets
[IEV 826-05-03]

3.5.34
toggle switch
sw itch having a lever (toggle), the movement of w hich resu lts either directly or indirectly in the
connection or disconnection of the switch terminations in a specified manner. Any indi rect
action through an actuating mechanism shall be such that the speed of connection and/or
disconnection is independent of the speed of lever movement
[IEV 581-10-11]

3.5.35
disconnector
mechanica l switch ing device w hich provides, in the open position , an isolating distance in
accordance with specified requirements
NOTE A disconnector is capabte of opening and closing a circuit when e 1ther negligible current is broken or made,
or when no significant change in the voltage across the terminals of each of the poles of the disconnector occurs
lt is also capable of carrying currents under normal circuit conditions and carrying currents for a specified time
under abnormal conditions s uc h as those of short-c ircuit.
[IEV 441-14-05]
60694 © IEC:1996+A1:2000+A2:2001 -43-

3.5.36
counter
device indicating the number of operating cycles a mechanical sw itching device has
accomplished

3.5.37
indicator light
lamp used as an indicator
[IEV 811 -3 1-06]

3.5.38
plug and socket-outlet
means enabling the connection at w ill of a flexible cable to fixed w iring
NOTE The application of the means i s s hown in f igure 1 of IEC 60309-1

3.5.39
cable coupler
means enabling the connection at w ill of tw o flexible cables
NOTE The applicatio n of the means i s s hown in figu re 1 of IEC 60309-1

3.5.40
appliance coupler
means enabling the connection at w ill of a flexible cable to the equipment
NOTE The applica tion of the means is shown in figure 1 of IEC 60309-1.

3.5.41
connector
componen! w hich terminales conductors for the purpose of providing connection and
disconnection to a suitable mating componen!
[I EV 581-06-01]

3.5.42
coil
set of series-connected turns, usually coaxial
[IEV 151-01-21]

3.5.43
static switching component
device in w hich the sw itching action is developed by electron ic, magnetic, optical or other
components w ithout mechanica l motion

3.5.44
secondary system
entity of
- control and auxiliary circu its, mounted on or adjacent to the switchgear or controlgear,
including circuits in central control cubicles;
- equipment for monitoring, diagnostics, etc ., that is part of the auxi liary circuits of the
switchgear or controlgear;
- circuits connected to the secondary terminals of instrument transformers, that are part of
the sw itchgear or controlgear

3.5.45
subassembly (of a secondary system)
part of a secondary system, w ith regard to function or position. A subassembly is normally
placed in a separate enclosure, and shall have its ow n interface
60694 © IEC:1996+A1:2000+A2:2001 -45-

3.5.46
interchangeable subassembly (of a secondary system)
subassembly w hic h is intended to be placed in various positions w ithin a secondary system ,
or intended to be replaced by other similar subassemblies. An interchangeable subassembly
has an accessible interface

3.6 Operation

3.6.1
dependent power operation
[IEV 441-16-14)

3.6.2
stored energy operation
[IEV 441-16-15)

3.6.3
positively driven operation
operation w hich , in accordance with specified requirements , is des ign ed to ensure that
auxiliary contact s of a mec hanical switching device are in the respect ive positions
corresponding to the open or closed posit ion of the main contacts
[IEV 441-16-12 , modified]
NOTE A positively driven operating device is made by the association of a moving part, linked mechanically to the
main contact of the primary circuit, without the use of springs, and a sensing element. In the case of mechanical
auxiliary contacts, this sensing element can be simply the fixed con tact, directly connected to the secondary
terminaL In the case where the function is achieved electronically, the sensing element can be a static transducer (optical,
mag netic , etc_) associated with a static switch, ar associated with an electromc or electro-optic transmitting element

3.6.4 Definitions relative to pressure (or density)

3.6.4.1
rated filling pressure for insulation Pre (or density Prel
the pressure in Pasca ls (Pa ), for insulation and/ or for swit ching, referred to the standard
atmospheric air conditions of +20 ºC and 101 ,3 k Pa (or density), w h ich may be exp ressed in
relative or absolute t erms, to w hich the assembly is filled b efare being pul into service, or
automatically replenished

3.6.4.2
rated filling pressure for operation Prm (or density Prm)
the pressure ( Pa ), referred to th e standard atmospheric air condit ions of +20 ºC and
101,3 kPa (or density), wh ich may be expressed in relative or absolute terms, to which the
control device is filled befare being put int o service or automatically replenished

3.6.4.3
alarm pressure for insulation Pae (or density Pael
the pressure (Pa ), for insulat ion and/or for switc hing , referred to the standard atmospheric air
cond it ions of +20 ºC and 101 ,3 kPa (or dens ity) , w h ich may be expressed in relative or
absolute t erms , at which a monitoring signal may be provided to ind icate that replenishment is
nec essary in a relatively short t ime

3.6.4.4
alarm pressure for operation Pam (or density Paml
t he pressure ( Pa ), referred to th e standard atmosphe ric air c ondit ions of +20 ºC and
101 ,3 kPa (or density), w hich may be expressed in re lative or absolute terms, al w hich a
monit oring signal may be prov ided t o indicate that replen ishment of t he c ontrol device is
necessary in a relatively short t ime
60694 © IEC:1996+A1:2000+A2:2001 -47-

3.6.4.5
mínimum functional pressure for insulation Pme (or density Pmel
the pressure (Pa), for insulation and/or for switching , referred to the standard atmospheric air
conditions of +20 ºC and 101 ,3 kPa (or density), w hich may be expressed in relative or
absolute terms , al which and above w hich rated characteristics of sw itchgear and controlgear
are maintained and at w hich a replenishment becomes necessary

3.6.4.6
mínimum functional pressure for operation Pmm (or density Pmml
the pressure (Pa), referred to the standard atmospheric air conditions of +20 ºC and
101,3 kPa (or density), which may be expressed in relative or absolute terms, at w hich and
above w hich rated characteristics of sw itchgear and controlgear are mainta ined and al which
a replenishment of the control device becomes necessary. T his pressure is often designated
as interlocking pressure

3.6.5 Definitions relating to gas and vacuum tightness

These definitions apply to all switchgear and controlgear w hich use vacuum or gas , other than
air at atmospheric pressure, as insulating or combined insulating and interrupt ing or operating
medium.

3.6.5.1
gas-filled compartment
a compartment of sw itchgear and controlgear in w hich the gas pressure is maintained by one
of the following systems:
a) controlled pressure system;
b) closed pressure system;
e) sealed pressure system.
NOTE Several gas-filled compartments may be permanently interconnec ted to fo rm a common g as-system (gas-
tight assembly).

3.6.5.2
controlled pressure system for gas
a volume w hich is automatically replenished from an externa ! or interna! gas sourc e
NOTE 1 Examples of c ontrolled pressure systems are air-blast circuit-brea kers or pneumatic operating
mechanisms.
NOTE 2 A volume may consist of several pe rmanen tly connected gas-fi lled compartments.

3.6.5.3
closed pressure system for gas
a volume w hich is replenished only periodically by manual connection to an externa! gas
so urce
NOTE Example of closed pressure system s are SF 6 single pressure circu it -breakers

3.6.5.4
sealed pressure system
a volume for w hich no further gas or vacuum processing is required during its expected
operating lite
NOTE 1 Examples of sealed p ressure systems are tu bes of v acuum circuit-breakers o r sorne SF5 circu it-breakers.

NOTE 2 Sealed pressure systems are completely assembled and tested in the factory

3.6.5.5
absolute leakage rate, F
the amount of gas escaped by time un it , expressed in Pa.m 3/s
60694 © IEC:1996+A1:2000+A2:2001 -49-

3.6.5.6
permissible leakage rate, Fp
the maximum permissible absolute leakage rate of gas specified by the manufacturer for
a part, a componen! or a sub-assembly, or by using the t ightness coordination chart (TC),
for an arrangement of parts, components or sub-assemblies connected together in one
pressure system

3.6.5.7
relativa leakage rate, Frel
t he absolute leakage rate related to the total amount of gas in the system al rated filling
pressure (or density). lt is expressed in percentage per year or per day

3.6.5.8
time between replenishments, T
the t ime elapsed betw een tw o replenishments performed either manually or automatically
w hen the pressure (density) reaches the alarm level , to compensate the leakage rate F

3.6.5.9
number of replenishments per day, N
the number of replenishments to compensate the leakage rate F. This value is applicable to
controlled pressure systems

3.6.5.1 O
pressure drop, Ap
the drop of pressure in a given time caused by the leakage rate F, w ithout replenishmen t

3.6.5.11
tightness coordination chart, TC
a survey document supplied by the manufacturer, used w hen testing parts, components or
sub-assembl ies, to demonstrate the relationship between the tightness of a complete system
and that of the parts , components and/or sub-assemblies

3.6.5.12
cumulative leakage measurement
a measurement w hich takes into account a ll the leaks from a given assembly to determine the
leakage rate

3.6.5.13
sniffing
the action of slow ly moving a leak meter sensing probe around a n assembly to locate a gas leak

3.6.6 Definitions relating to liquid tightness

These definitions apply to all sw itchgear and controlgear which use liquids as insulating ,
combined insulating and interrupting, or control med ium with or w ithout permanent pressure.

3.6.6.1
controlled pressure system for liquid
a volume w hich is automatically replenished w ith liquid

3.6.6.2
closed pressure system for liquid
a volume which is manual ly replenished only periodically w ith liquid

3.6.6.3
absoluta leakage rate, F¡¡q
t he amount of liquid escaped by time unit, expressed in cm 3/ s
60694 © IEC:1996+A1:2000+A2:2001 - 51 -

3.6.6.4
permissible leakage rate, Fp(liq)
the maximum permissible leakage rate specified by the manufacturer fer a liquid pressure system

3.6.6.5
number of replenishments per day, N 1;q
the number of replenishments to compensate the leakage rate F 1,q. This value is applicable to
controlled pressure systems

3.6.6.6
pressure drop, &P1;q
the drop in pressure in a given time caused by the leakage rate F1;q without replen ishment

3.7 Characteristic quantities

3.7.1
isolating distance
[IEV 441-17-35]

3.7.2
degree of protection
t he extent of protection provided by an enclosure against access to hazardous parts , against
ingress of solid foreign objects and/or ingress of w ater and verified by standardized test
methods [3.3 of IEC 60529]

3.7.3
rated value
a quantity value assigned, generally by a manufacturer, fer a specified operating condition of
a componen! device or equipment
[IEV 151-04-03]

3.8 lndex of definitions

A
Absolute leakage rate ................................. 3.6.5.5 and 3.6.6.3
Alarm pressure fer insulation ...... . 3.6.4.3
Alarm pressure for operation ........ . 3.6.4.4
Ambient air temperature .................. 3.1.16
Auxiliary circuit ..... 3.5.4
Auxiliary contact 3.5.8
Auxiliary sw itch 3.5.6

e
Closed pressure system for gas ... ......... . 3.6.5.3
Closed pressure system for liquid 3.6.6.2
Connection ... 3.5.10
Contact 3.5.3
Control circuit 3.5.5
Control contact ...... . 3.5.9
Control sw itch.. .... ................................ . 3.5.7
Controlled pressure system for gas ................................ . 3.6.5.2
Controlled pressure system for liquid . ................ . ...... 3.6.6.1
Cumulative leakage measurement 3.6.5. 12
60694 © IEC:1996+A1:2000+A2:2001 - 53 -

Defect.. .... ... 3.1.15

Degree of protection .. ... 3.7.2
Dependen! power operation ... 3.6.1
Diagnostic tests. 3.1.8
Dow ntime ...... 3.1.11

E
Enclos ure 3.5.1
Examinat ion .... 3.1.9
Externa! insulation .. 3.1.2
F
Failure .. 3.1.12

G-1
Gas-filled compartment 3.5.5.1
lndependent power operation .... 3.6.2
lnspection .. 3.1.7
IP Cede ... ... 3.1.3
lsolating distance .... 3.7.1

L- M
Low energy contact.. 3.5.14
Maintenance .. . 3.1.5
Major failure ... . 3.1.13
Mínimum functional pressure fer insulation . 3.6.4.5
Mínimum functional pressure fer operation ........................... . 3.6.4.6
Minor failure ....... ..... 3.1.14
Monitoring device ....... ........ ...... . 3.5.12

N-0
Number of replenishments per day 3.6.5.9 and 3.6.6.5
Overhaul 3.1.10

p
Permissible leakage rate ... 3.6.5.6 and 3.6.6.4
Pilot switch ....... . 3.5.13
Position indicating device. ...... 3.5.11
Positively driven ..... 3.6.3
Pressure drop .. 3.6.5.1 O and 3.6.6.6
Protection provided by an enclosure against access to hazardous parts . 3.1.4
60694 © IEC:1996+A1:2000+A2:2001 - 55 -

R
Rated filling pressure for insulation ....... 3.6.4.1
Rated filling pressure for operation ........ ..... 3.6.4.2
Rated value ..... ...... . 3.7.3
Relative leakage rate 3.6.5.7

s
Scheduled maintenance 3.1.6
Sealed pressure system ....... 3.6.5.4
Self-protected sw itchgear 3.2.1
Sniffing . 3.6.5.13
Sw itchgear and controlgear 3.1.1
T
Test specimen 3.2.2
Tightness coordination chart .... . 3.6.5.1 1
Time betw een replenishments .. . 3.6.5.8
Transport unit 3.3.1

4 Ratings

The common ratings of sw itchgear and cont rolgear, including their operating devices and
auxiliary equipment, should be selected from the follow ing :

a) rated v oltage ( U,)

b) rated insulation level
c ) rated frequency (f,)
d) rated normal curren! (/,)
e) rated short-t ime w ithstand curren! Ukl
f) rated peak w ithstand curren! (/p)
g) rated duration of short circuit (tk)
h) rated supply voltage of closing and opening devices and of auxiliary circuits (Ua)
i) rated supply frequency of clos ing and opening devices and of auxil iary circuits
j) rated pressure of compressed gas supply for ins ulation or operation.
NOTE Other rated characteristics may be necessary and will be specified in the relevant IEC standards.

4.1 Rated voltage ( U,)

The rated voltage indicates the upper limit of the hig hest voltage of sy stems for w hich the
sw itchgear and controlgear is intended. Standard values of rated voltages are given below:

NOTE Far editorial reasons , mainly due to the characteristics of the transi ent recovery voltages, the s ubdivision
in voltage ranges differs from that in IEC 60038
60694 © IEC:1996+A1:2000+A2:2001 - 57 -

4.1.1 Range I for rated voltages of 245 kV and below

Series 1 3,6 kV - 7,2 kV - 12 kV - 17,5 kV - 24 kV - 36 kV - 52 kV - 72 ,5 kV - 100 kV -

123 kV- 145 kV - 170 kV- 245 kV.
Series 11 (based on the curre ni practice in North America): 4, 76 kV - 8,25 kV - 15 kV -
25,8 kV - 38 kV - 48,3 kV - 72 ,5 kV.

4.1.2 Range II for rated voltages above 245 kV

300 kV - 362 kV - 420 kV - 550 kV - 800 kV.

4.2 Rated insu lation level

The rated insulation level of switchgear a nd controlgear shall be selected from the values
given in tables 1 and 2.

In these tables , the w ithstand voltage applies al the standardized reference atmosphere
(temperature , pressure and humidity) specified in IEC 60071-1. For special service conditions,
see 2.2.

The rated w ithstand voltage values fer lightning impulse voltage (Up), switching impulse
voltage (U5 ) (when applicable), and pow er-frequency voltage ( Ud) shall be selected w ithout
crossing the horizontal marked lines. The rated insulation level is specified by the rated
lightning impulse withstand voltage phase to earth.

Fer most of the rated voltages, several rated insulation levels exist to allow fer application of
difieren! performance criteria or overvoltage patterns. The choice should be made considering
the degree of exposure to fast-front and slow -front overvoltages , the type of neutral earthing
of the system and the type of overvoltage limiting devices (see IEC 60071-2).

The "common values" as used in tables 1a and 1 b apply to phase-to-ea rth, betw een phases
and across the open switching device, if not otherwise specified in this standard. The
w ithstand voltage values "across the isolating distance" are valid only fer the switch ing
devices where the clearance betw een open contacts is designed to meet the safety
requirements specified fer disconnectors.

For further infermation about insulation levels, see annex D.

60694 © IEC:1996+A1:2000+A2:2001 - 59 -

Table 1 a - Rated insulation leve Is for rated voltages

of range 1, series 1

Rated Rated short-duration power-frequency Rated lightning impulse

voltage withstand voltage withstand voltage
u, Ud u.
kV (r.m.s. value) kV (r.m.s. value) kV (peak value)

Common value Across the Common value Across the isolating

isolating distance distance
(1 ) (2) (3 ) (4) (5)

3,6 10 12 20 23
40 46
7,2 20 23 40 46
60 70
12 28 32 60 70
75 85
17,5 38 45 75 85
95 110
24 50 60 95 110
125 145
36 70 80 145 165
170 195
52 95 110 250 290
72,5 140 160 325 375
100 150 175 380 4 40
185 210 450 520
123 185 210 450 520
230 265 550 630
145 230 265 550 630
275 315 650 750
170 275 315 650 750
325 375 750 860
245 360 415 850 950
395 460 950 1 050
460 530 1 050 1 200
60694 © IEC:1996+A1:2000+A2:2001 - 61 -

Table 1b - Rated insulation leve Is for rated voltages of range I, series 11

(used in North America)*

Rated Rated short-duration power-frequency Rated lightning impulse

voltage withstand voltage withstand voltage
u, Ud u.
kV (r.m.s. val ue) kV (r. m.s. value) kV (peak value)

Common value Across the isolating distance Common Across isolating

value distance
Dry Wet""" Dry Wet"""

(1) (2) (2 a ) (3) (3 a ) (4) (5)

4,76 19 - 21 - 60 70
8 ,25 26 24 29 27 75 80
35 30 39 33 95 105
15 35 30 39 33 95 105
50 45 55 50 110 125
25,8 50 45 55 50 125 140
70 60 77 66 150 165
38 70 60 77 66 150 165
95 80 105 88 200 220
48,3 120 100 132 110 250 275
72,5 160 140 176 154 350 385
For rated voltages higher than 72,5 kV up to and including 245 kV, the values of table 1a are applicable.
.. W et v alues are a 10 s withstand for equipment used outdoors. See 9.2 of IEC 60060- 1
60694 © IEC:1996+A1:2000+A2:2001 -63-

Table 2a - Rated insulation levels for rated voltages of range 11

Rated Rated short-duration Rated switching impulse Rated lightning

voltage power-frequency withstand voltage impulse
withstand voltage withstand voltage
u, Ud u, uP
kV (r.m.s.
value) kV ( r_ m _s value) kV (peak value) kV (peak v alue)

Phase-to- Across Phase-to- Between Across Phase-to- Across open

earth and open earth and phases isolating earth and switchi ng
between switching across distance between device and/or
phases devi ce open (notes 3 phases isolating
and/or switching and 4) (notes 1, d i stance
(note 3) isolating device 2 and 3 )
(notes 2
distance
and 3 )
(note 3)

( 1) ( 2) (3) (4) ( 5) (6) (7) (8)

300 380 435 750 1 125 700 (+ 245) 950 950 (+ 170)

850 1 275 1 050 1 050 ( + 170)

362 450 520 850 1 275 800 (+ 295) 1 050 1 050 ( + 205)

950 1 425 1 175 1 175 ( + 205)

420 520 610 950 1 425 900 (+ 345) 1 300 1 300 (+ 240)

1 050 1 575 1 425 1 425 ( + 240)

550 620 800 1 050 1 680 900 (+ 450) 1 425 1 425 ( + 315)

1 175 1 760 1 550 1 550 ( + 315)

800 830 1150 1 300 2 210 1 100 (+ 650) 1 800 1 800 (+ 455)

1 425 2 420 2 100 2 100 ( + 455)

NOTE 1 Column (6) is a lso applicable to sorne circuit-breakers, see IEC 60 056.

NOTE 2 In col umn (6), val ues in brackets are the peak val ues of the power-frequenc y voltage Ur ✓2/ ✓3 applied
to the oppos ite te rminal (combined v oltage)

In column (8), va lues in brackets are the peak va lues of the power-frequency voltage 0,7 Ur .fi./ /i applied to the
o pposite terminal (combined voltage)
See annex D
NOTE 3 Va lues of col umn (2) a re applicable
a ) far type tests, phase-to-earth,
b) far rout ine tests , phase-to-earth, phase-to -p hase, and across the open switching device.
Values of columns (3), (5), (6) and (8) are applicable for type tests only

NOTE 4 These value s a re derived using the multipl yi ng factors stated in table 3 o f IEC 60071 -1 .
60694 © IEC:1996+A1:2000+A2:2001 - 65 -

Table 2b - Additional rated insulation levels in North America for range 11

Rated Rated short-duration Rated switching impulse Rated lightning

voltage power-frequency withstand voltage impulse
withstand voltage withstand voltage
u, u. u, uP
kV (r.m.s. kV (r.m.s. v alue) kV (peak value) kV (peak value)
value)
Phase-to- Across Phase-to- Between Across Phase-to- Across open
earth and open earth and phases isolating earth and switchi ng
between switching across dist ance between dev ice andlor
phases device open (notes 3 phases isolating
and/or switching and 4) (notes 1, distan ce
(note 3) isolating device 2 and 3)
distan ce (notes 2
and 3)
(note 3)

( 1) (2) (3) (4) (5) (6 ) (7) (8)

362 520 610 950 1 425 800 (+ 295) 1300 1 300 (+ 205)

550 710 890 1 175 2 210 900 ( + 450) 1800 1 800 (+ 315)

The notes are the same as those to tab le 2a

4.3 Rated frequency (f,)

The stan dard values of the rated frequency are 16 2/ 3 Hz, 25 Hz, 50 Hz and 6 0 Hz.

4 .4 Rated normal current and temperature rise

4.4.1 Rated normal current (/,)

The rat ed normal curren! of switchgear and controlgear is !he r.m.s. value of !he curren! which
sw itchgear and controlgear shall be able to carry continuously under specified conditions of
use and behaviour.

The v alues of rated normal curren Is should b e selected f rom !he R 1O serie s, specified
in IEC 60059.

NOTE 1 The R 1O series comprises the numbers 1 - 1,25 - 1,6 - 2 - 2 ,5 - 3, 15 - 4 - 5 - 6,3 - 8 and their
products by 10n
NOTE 2 Rated currents far temparary ar far intermittent duty are subjec t to agreement between manufacturer and
user

4.4.2 Temperature rise

The temperat ure rise of any par! of sw itchgear and c ontrolgear al an ambient air temperature
no! exceeding 40 ºC shall no! exceed the temperature-rise limits specified in table 3 under !he
conditions specified in !he test clauses.
60694 © IEC:1996+A1:2000+A2:2001 - 67 -

Table 3 - Limits of temperature and temperature rise for various parts, materials and
dielectrics of high-voltage switchgear and controlgear

Maximum value
Nature of the part, of the material and of the dielectric Temperature Temperature rise at
(See points 1, 2 and 3) (See note) ambient air tempera ture
not exceeding 40 º C

ºC K
1 Contacts (see point 4 )
Bare-copper or bare-copper alloy
- in air 75 35
- in SF 6 (sulphur hexafluoride) (see point 5) 105 65
- in oíl 80 40
Silver-coated or nickel-coated (see point 6)
- m a1r 105 65
- in SF 6 (see point 5) 105 65
- in oil 90 50
Tin-coaled (see point 6)
- in air 90 50
- in SF5 (see point 5) 90 50
- in oil 90 50
2 Connection, bolted or the equivalent (see point 4)
Bare-copper, bare-copper alloy ar bare-a luminium alloy
- in a ir 90 50
- in SF6 (see point 5) 115 75
- in oil 100 60
Silver-coated or nickel-coated see point 6)
- in air 115 75
- in SF 6 (see point 5) 115 75
- in oil 100 60
Tin-coated
in air 105 65
- in SF 6 (see point 5) 105 65
- in oil 100 60
3 AII other contacts or connections made of bare metals
or coated with other materials (see point 7) (see point 7)
4 Terminals for the connection to externa! cond uctors by
screws or bolts (see point 8)
- bare 90 50
- silver, nickel or tin-coated 105 65
- other coatings (see point 7) (see point 7)
5 Oil for oil switching devices (see points 9 and 1 O) 90 50
6 Metal parts acting as springs (see point 11) (see poi ni 11)
7 Materials used as insulation and metal parts in contact
with insulation of the following c lasses (see point 12)
- y 90 50
- A 105 65
- E 120 80
- B 130 90
- F 155 115
- Enamel: oil base 100 60
synthetic 120 80
- H 180 140
- C other insulating material (see point 13) (see point 13)
8 Any part of metal or of insulating material i n contact 100 60
with oil, except contacts
9 Accessible parts
- expected to be touched in normal ope rat ion 70 30
- whic h need not to be touched in normal operation 80 40
NOTE The points referred to in this table are those of 4 .4.3
60694 © IEC:1996+A1:2000+A2:2001 -69-

4.4.3 Particular points of table 3

The follow ing points are referred to in table 3 and complete it.

Point 1 According to its function , the same part may belong to several categories as listed
in table 3.
In this case the permissible maximum values of temperature and temperature rise
to be considered are the low est among the rele van! categories.
Point 2 For vacuum sw itching devices, the values of temperature and temperature-rise
limits are not applicable for parts in vacuum. The remaining parts shall not exceed
the values of temperature and temperature rise g iven in table 3.
Point 3 Care shall be taken to ensure that no damage is caused to the surrounding
insulating materials.
Point 4 When engaging parts have different coatings or one part is of bare material, the
permissible temperatures and temperat ure rises shall be:
a) for contacts , those of the surface material having th e lowest value permitted in
item 1 of table 3;
b) for connections, those of the surface material h aving the highest value permitted
in item 2 of table 3.
Point 5 SF5 means pure SF5 ora mixture of SF5 and other oxygen-free gases.
NOTE 1 Due to t he absence of oxyg en, a ha rmonization of the lim its of temperature far diffe re nt contact and
connection parts in the case of SF 6 sw itchge ar appears appropri ate_ In accordance w ith I EC 60943, wh ich gives
guidance far the specifi cation of permissible temperatu re s, the pe rmissible temperature timits for bare copper and
bare copp er alloy parts can be equalized to the values far silver-coated or nickel -coated parts in the case of SF6
atmospheres.
In the particu lar case of tin -coate d parts, due to fretting corrosion effects (refer to IEC 60943) an increase o f the
permissible temperatures is not applicable, even under the oxygen-free conditions o f SF6. Therefore t he initial
values for tin-coated parts are kept.
NOTE 2 Temperature rises for bare copper and silver-coated contacts in SF6 are under considera tion.

Point 6 The qua lity of the coated contacts sha ll be suc h that a continuous layer of coating
material remains in the contact area :
a) after making and breaking test (if any) :
b) after short-time w ithstand curren! test:
c) after the mechanical endurance test:
according to the relevan! spec ifications for each equipment. Otherwise , the
contacts shall be regarded as "bare".
Point 7 W hen materials other than those given in table 3 are used, their properties shall be
considered , notably in order to determine the maximum permissible temperature
rises.
Point 8 The values of temperature and temperature rise are valid ev en if the conductor
connected to the terminals is bare.
Point 9 Al the upper part of the oil.
Point 1O Special consideration should be given w hen low flash -point oil is u sed in regard to
vaporization and oxidation.
Point 11 The temperature shall not reach a value w here the elasticity of the material is
impaired.
Point 12 Classes of insulating materials are !hose given in IEC 60085.
Point 13 Limited only by the requirement not to cause any damage to surrounding parts.
60694 © IEC:1996+A1:2000+A2:2001 - 71 -

4.5 Rated short-time withstand current (/k)

The r.m.s. value of the curren! which the switchgear and controlgear can carry in the closed
position during a specified short time under prescribed conditions of use and behaviour.

The standard value of rated short-time withstand curren! should be selected from the R 10
series specified in IEC 60059, and shall be equal to the short-circuit rating assigned to
sw itchgear and controlgear.

NOTE The R 1O series comprises the numbers 1 - 1,25 - 1,6 - 2 - 2 ,5 - 3, 15 - 4 - 5 - 6 ,3 - 8 and their products
by 10".

4.6 Rated peak withstand current (/p)

The peak curren! associated with the first major loop of the rated short-time w ithstand curren!
w hich switchgear and controlgear can carry in the closed position under prescribed conditions
of use and behaviour.

The rated peak withstand curren! shal l correspond to the rated frequency. For a rated
frequency of 50 Hz and below it is equal to 2 ,5 times the rated short-time withstand curren!,
and for a rated frequency of 60 Hz it is equal to 2,6 times the rated short-time withstand
curren!.

NOTE Values higher than 2 ,5 or 2 ,6 times the rated short-time withstand current may be required according to the
characteristics of the system.

4.7 Rated duration of short circuit (tk)

The interval of time for w hich sw itchgear and controlgear can carry, in the closed position, a
curren! equal to its rated short-time withstand curren!.

The standard value of rated duration of short circuit is 1 s.

lf it is necessary, a value lower or higher than 1 s may be chosen . The recommended values
are 0,5 s, 2 s and 3 s.

4.8 Rated supply voltage of closing and opening devices and of auxiliary
and control circuits (Ua)

4.8.1 General

The supply voltage of closing and opening devices and auxi liary and control circuits shall be
understood to mean the voltage measured al the circuit terminals of the apparatus itself
during its operation, including , if necessary, the auxil iary resistors or accessories supplied or
required by the manufacturer to be installed in series with it, but not includ ing the conductors
for the connection to the electricity supply.

The supply system should preferably be referenced to earth (i.e. not completely f loating) in
order to avoid the accumulation of dangerous static voltages. The location of the earthing
point should be defined according to good practice.

lt should be noted that normal operation of equipment is to be assured when the supply
voltage is within the tolerances described in 4.8.3.
60694 © IEC:1996+A 1:2000+A2:2001 - 73 -

4 .8.2 Rated vo ltage (U0 )

The rated supply voltage should be selected f rom the st andard values giv en in t ables 14
and 15. The values marked wit h an ast erisk are preferred values f or electronic auxiliary
equipment.

Table 14 - Direct curren! voltage

u.
V

24
48'
60
110• or 125
220 or 250

Table 15 - Alternating curren! voltage

Thr ee-phase, th ree-wire or Sin g le -phase, t hree-w ire Sin g le -phase, two-wire
four-wire system s system s systems
V V V

- 1201240 120
1201208 - 120
(22 01380) - (220)
2301400· - 230•
(24 01415) - (240)
2771480 - 277
3471600 - 347
NOTE 1 The lower values in the first column of this table are voltages to neutral and the higher values
are voltages between phases. The lower valu e in the second column is the voltage to neutral and the
higher value is the voltage between lines.
NOTE 2 The va lue 230/ 400 V indicated in thi s table should be, in the future , the only IEC standard
voltage and its adoption is recom mended in new systems _ The voltage variati ons of existing systems
at 2201380 V a nd 24 01415 V should be brought within the range 2301400 V± 10 % . The reduc tion of this
range will b e considered at a later stage of standardization.

4 .8.3 Tolerances

The relative tolerance of a.c. and d.c. pow er supply in normal duty measured at the input
of the auxiliary equipment (electronic controls , supervision, monitoring and communication)
is85 % to11 0%.

Far supply voltages less t han the mínimum stated far powe r supply, precautions shall be
taken to preven! any damage to e lectronic equipment and/or unsafe operation due to its
unpredictable behaviour.

Far operation of shunt opening releases , the relat ive tolerance shall comply wit h th e requ ire-
ment s of 5 .8 .
60694 © IEC:1996+A1:2000+A2:2001 - 75 -

4.8.4 Ripple voltage

In case of d.c. supply, the ripple voltage , that is the peak-to-peak va lue of the a. c. componen!
of the supply voltage al the rated load, shall be limited to a value not greater than 5 % of the
d.c. componen!. The voltage is measured at the supply terminals of the auxiliary equipment.
IEC 61000-4-17 applies.

4.8.5 Voltage drop and supply interruption

IEC 61000-4-29 should apply to electrical and electronic components.

As far as supply interruptions are concerned , the system is considered to perform correctly if

- there are no false operations;

- there are no false alarms or false remate signalling;
- any pending action is correctly completed, even w ith a short delay.

4.9 Rated supply frequency of closing and opening devices and of auxiliary circuits

The standard values of rated supply frequency are DC , 50 Hz and 60 Hz.

4.1 O Rated pressure of compressed gas supply far insulation and/or operation

The standard va lues of rated pressure are:

0,5 MPa - 1 MPa - 1 ,6 MPa - 2 M Pa - 3 MPa - 4 M Pa,

unless otherwise specified by the manufacturer.

5 Design and construction

5.1 Requirements far liquids in switchgear and controlgear

The manufacturer shall specify the type and the required quantity and quality of the liquid to
be used in switchgear and controlgear and provide the user w ith necessary instructions far
renew ing the liquid and mainta ining its required quantity and quality (see 10.4.1 item d)) .

5.1.1 Liquid level

A device for checking the liquid level, preferably during service , w ith indication of mínimum
and maximum limits admissible for corree! operation, shall be provided.

NOTE This is not a pplicable to dash-pots.

5.1.2 Liquid quality

Liquids far use in sw itchgear and controlgear shall comply w ith the instructions of the
manufacturer.

Far oil-fil led switchgear and controlgear, new insu lating oil shall comply w ith IEC 60296.
60694 © IEC:1996+A1:2000+A2:2001 - 77-

5.2 Requirements for gases in switchgear and controlgear

The manufacturer shall specify the type and the required quantity, quality and density of the
gas to be used in switchgear and controlgear and provide the user with necessary instructions
for renew ing the gas and maintaining its required quantity and quality (see 10.4.1 a)), except
for sealed pressure systems.

For sulphur hexafluoride-filled sw itchgear and controlgear, new sulphur hexafluoride shall
comply with IEC 60376.

In order to preven! condensation , the maximum allow able moisture content within gas-filled
sw itchgear and controlgear filled w ith gas at rated fil ling density for insulation Pre shall be
such that the dew -point is not higher than -5 º C for a measurement at 20 ºC. Adequate
correction shall be made for measurement made at other temperatures. For the measurement
and determination of the dew -point, refer to IEC 60376B and IEC 60480.

Parts of hig h-voltage switchgear and controlgear housing compressed gas shal l comply w ith
t he requirements laid dow n in the re levan! IEC standards.
NOTE Attention is drawn to the need to comply with local regulation relevant to pressure vessels.

5.3 Earthing of switchgear and controlgear

The frame of each switching device shall be provided with a reliable earthing terminal having
a clamping screw or bolt for connection to an earthing conductor suitable for specified fault
conditions. The diameter of the clamping screw or bolt shall be at least 12 mm. The
connecting point shal l be marked with the "protect ive earth" symbol , as indicated by symbol
No. 5019 of IEC 60417. Parts of metallic enclosures connected to the earthing s ystem may be
considered as an earthing conductor.

5.4 Auxiliary and control equipment

5.4.1 Enclosures

5.4.1.1 General

The enclosures for low-voltage control and auxiliary circuits shall be constructed of materials
capable of withstanding the mechanical , electrica l and thermal stresses , as w ell as the effects
of humidity w hich are likely to be encountered in normal service.

5.4.1.2 Protection against corrosion

Protect ion against corrosion s hall be ensured by t he use of su itable materials or by the
application of suitable protective coatings to the exposed surfaces , taking into account
t he intended conditions of use in accordance w ith the service cond itions stated in clause 2.

5.4.1.3 Degrees of protection

The degree of protection provided by an enclosure for low-voltage auxiliary and control
circuits s hall be in accordance w ith 5 .13.

Openings in cable entries, cover plates , etc. shall be so designed that, w hen t he cables are
properly installed , the stated degree of protection of an enclosure for low -voltage auxiliary and
control c ircuits, as defined in 5.13, shall be obtained. T his implies that a means of entry,
suitable for the application stated by the manufacturer, should be selected.

Any ventilation open ings shall be shielded or arranged so that the same degree of protection
as that specified for the enclosu re is obtained.
60694 © IEC:1996+A1:2000+A2:2001 - 79 -

5.4.2 Protection against electric shock

5.4.2.1 Protection by segregation of auxiliary and control circuits from

the main circuit

Auxiliary and control equipment w hich is installed on !he frame of sw itching devices shall be
suitably protected against disruptive discharge from !he main circuit.

The w iring of auxiliary and control circuits, w ith !he exception of short lengths of w ire al
terminals of instrument transformers , tripping coi ls , auxiliary contacts , etc. shall be e ither
segregated from !he main c ircuit by earthed metallic partitions (for example, tubes) or
separated by partitions (for example, tubes) made of insulating mate rial.

5.4.2.2 Accessibility of auxiliary and control equipment

Auxiliary and control equipment requiring attention during service shall be accessible w ithout
danger of direct contact w ith high-voltage pa rts.

Where !he reduction of safety distances abov e !he servic ing level due to abnormal
environmental conditions (for example a ccumulation of snow, sand , etc .) needs to be
considered, !he mínimum height of live parts above it shall be increased.

5.4.3 Fire hazard

5.4.3.1 General

As !he risk of fire is present in auxiliary and control c ircuits , !he likelihood of fire shall be
reduced under conditions of normal use, and even in the event of foreseeable abnormal use,
malfunction or fa ilure.

The f irst objective is to preven! ignition due to an electrically energized par!. The second
objective is to limit !he fire impact, if fire or ignition occurs inside !he enclosure.

5.4.3.2 Components and circuit design

In normal operation , heat dissipation of components is generally smal l. How ever, a

componen! may, w hen faulty or in an overload condition resu lting from an externa! fault,
generate excess heat such that fire may be initiated .

The manufacturer should take every care so that, by appropriate circuit design and
protections , interna! faults or overload conditions w ill no! give rise to fire hazard. The
manufacturer should design or choose components w hich have a power rating higher !han
necessary under normal conditions and self-ignition characteristics determined with respect to
!he maximum fault power of !he circuit. Spec ial attention should be given to resistors.

Consideration should be given to !he assembly of components and !he relative arrangement
of !hose that may dissipate excessive heat by provid ing around them sufficient space.

5.4.3.3 Managing tire impact

Provisions should be taken in order to manage fire impact. Enclosures shou ld be constructed ,
insulated, made watertight , etc. w ith materials sufficiently resista n! to probable ignition and
heat sources situated within. The manufacturer should consider that, if it ignites , a componen!
may emit melted flaming material and/or glow ing particles.
60694 © IEC:1996+A1:2000+A2:2001 -81 -

5.4.4 Components installed in enclosures

5.4.4.1 Selection of components

Components installed in enclosures shal l comply w ith the requirements of the relevan!
IEC standards. Where an IEC standard does not exist. or the componen! is qualified w ith
reference to another standard (issued by a country or another organization). the criteria for
selection should be agreed between the manufacturer and the user.

AII components used in the aux iliary and control circuits shall be designed or selected to be
operational w ith their rated characteristics over the whole actual service conditions inside
auxiliary and control circuits enclosures that can differ from the externa! service conditions
specified in clause 2.

Suitable precautions (insulation , heating , ventilation, etc .) shall be taken to ensure th at !hose
service conditions essential for proper functioning are maintained, for example, heaters to
maintain the required mínimum temperature for the corree! operation of relays, contactors ,
low -voltage sw itches, meters, counters, push-buttons , etc. according to the relevan!
specifications.

The loss of !hose precaution means shall not cause failures of the components nor untimely
operation of sw itchgear and controlgear. The operation of sw itchgear and controlgear shall be
possible during 2 h after the loss of !hose means. After this period , a non-operation of the
sw itchgear and controlgear w ith its associated auxiliary and control circuit is acceptable
provided that the functionality resets to its original characteristics w hen environmental
conditions inside the enclosure for auxiliary and control circuits are back to the specified
service conditions.

Where heating is essential for corree! functioning of the equipment, monitoring of the heating
circuit shall be provided.

In the case of sw itchgear and controlgear designed for outdoor installation , suitable arrange-
ments (ventilation and/ or interna! heating, etc. ) shall be made to preven! harmful
condensation in low-voltage control and auxiliary circuits enclosures.

Polarity reversa! at the interfacing point shal l not damage auxiliary and control circuits.

5.4.4.2 lnstallation of components

Components shall be insta lled in accordance w ith the instructions of their manufacturer.

5.4.4.3 Accessibility

Closing and opening actuators and emergency shut-dow n system actuators should be located
between 0,4 m and 2 m abov e servicing level. Other actuators should be located at such
a height that they can be easily operated , and indicating devices should be located at such a
height that they can be easily readable.

Structure-mounted or floor-mounted enclosures for low -vo ltage auxiliary and control circuits
should be installed at such a height, with respect to the servicing level, that the above
requirements for accessibility, operating and reading heights are met.

Components in enclosures should be so arranged as to be accessible for mounting, w iring ,

maintenance and replacement. Where a componen! may need adjustment during its service
lite, easy access should be considered w ithout danger of electrical shock.
60694 © IEC:1996+A1:2000+A2:2001 -83-

5.4.4.4 ldentification

ldentification of components installed in enclosures is the responsibility of the manufacturer

and it shall be in agreement w ith the indication on the w iring diagrams and draw ings. 11 a
componen! is of the plug-in type, an identifying mark shou ld be placed on the componen! and
on the fixed part w here the componen! plugs in.

Where mixing of components or voltages could cause confus ion, consideration should be
given to more explicit marking.

5.4.4.5 Requirements for auxiliary and control circuit components

5.4.4.5.1 Cables and wiring

The nominal cross-sectional area and characteristics of conductors and electric cables shall
comply with the requirements of IEC 60228.

The insu lation on cables shall comply w ith applicable IEC standards (for example, polyvinyl
chloride insulated cables shal l comply w ith the requirements of IEC 60227 or IEC 60502-1 ,
rubber insulated cables shall comply with the requirements of IEC 60245, etc. ).

The choice of cables to connect together control and auxiliary c ircuit enclosures is the
responsibility of the manufacturer. The choice is governed by the curren! that must be carried,
by the voltage drop and the curren! transformer burden , by the mechanical stresses to wh ich
the cable is subjected and by the t ype of insulation. The choice of conductors in enclosures is
also the responsibility of the manufacturer.

Suitable means shall be provided for the connection of externa! w iring, for example terminal
blocks , plug-in terminations, etc.

Cables betw een tw o termina l blocks shall have no intermediate splices or soldered joints .
Connections shall be made al fixed terminals.

lnsulated conductors shall be adequately supported and shall not rest against sharp edges.

Wiring shou ld take into account the proximity of heating elements.

The available wiring space shall permit spreading of the cores of multi-core cables and the
proper termination of the conductors. The conductors shall not be subjected to stresses that
reduce their normal lite.

Conductors connected to apparatus and indicating devices in covers or doors shall be so

installed that no mechanical damage can occur to the conductors as a result of movement of
these covers or doors.

Only one conductor should be connected to a terminal; the connection of tw o or more

conductors to one terminal is permissible only in those cases where the terminal is designed
for this purpose.

The method and extent of identification of conductors, fer example by numbers, colours or
symbols, is the responsibi lity of the manufacturer. ldentification of conductors shall be in
agreement w ith the w iring diagrams and draw ings, and the specification of the user, if
applicable. This identification may be limited to the ends of the conductors. Where
appropriate, identification of wi ring according to IEC 60445 may be applied.
60694 © IEC:1996+A1:2000+A2:2001 -85-

5.4.4.5.2 Terminals

Terminal blocks intended to connect round copper conductors shall comply w ith the
requirements of I EC 6094 7-7-1.

Protective conductor terminal blocks intended to connect round copper conductors shall
comply with the requirements of IEC 60947-7-2.

Terminals shall maintain the necessary contact pressure, corresponding to the curren! rating
and the short-circuit curren! of c ircuits.

Terminal blocks for wiring components inside the enclosure shall be chosen according to the
cross-section of the conductors used.

lf facilities are provided for connecting incoming and outgoing neutral , protective and PEN
conductors, they shall be s ituated in the vicinity of the associated phase conductor terminal.

ldentif ication of terminals shall comply w ith the requirements of IEC 60445 and shall be in
agreement w ith the indications on the wiring diagrams and draw ings, and the specification of
the user, if applicable.

5.4.4.5.3 Auxiliary switches

Auxiliary sw itches shal l be suitable for the number of electrical and mechanical operating
cycles specified for the sw itching device.

Auxiliary sw itches , w hich are operated in conjunction w ith the main contacts, shal l be
positively driven in both directions. How ever, in sorne cases w here the speed of the operating
mechanism is not very fast and by agreement betw een the manufacturer and the user, a set
of tw o one-w ay positively driven auxi liary contacts (one for each direction ) can be used,
provided that dependability constraints are satisfied.

5.4.4.5.4 Auxiliary and control contacts

Auxiliary and control contacts shall be suitable for their intended duty in terms of
environmental conditions (see 5.4.3.1 ), making and breaking capacity and timing of the
operation of the auxiliary and control contacts in relation to the operation of the main
equipment.

Auxiliary and control contacts shall be suitable for the number of electrical and mechanical
operating cycles specified for the sw itching device.

Where an auxiliary contact is made available to the user, the technical documents provided by
t he manufacturer should contain information regard ing the class of this contact.

The operational characteristics of the auxiliary contacts should comply w ith one of the classes
show n in table 16.
60694 © IEC:1996+A1:2000+A2:200 1 - 87 -

Table 16 - Auxiliary contacts classes

OC current

Class Rat ed Rated s h o rt• B reaking c apacity

continuous time withstand
current current ~48 V 11 O V ~ U, ~ 250 V

1 10A 100 A/30 ms 440 W

2 2A 100 A/30 ms 22 W

3 200 mA 1 A/30 ms 50 mA

NOTE 1 This table refers to auxiliary contacts (IEV 441-15-1 0) which are included in an auxiliary circuit
and mechanicaUy operated by the switching device. Control contacts [IEV 441 - 15-09) which are included in
a control circuit of a mechan ical switching d evice may be concerned by th is table.
NOTE 2 lf no sufficient current is flowing through the contact, oxidation may increase the resistance.
Therefore, a mínimum value of current may be required far class 1 contact.
NOTE 3 In the case of the application of static contacts, the rated short-time withstand current may be
reduced if current limiting equipment, other than fuses, is employed.
NOTE 4 For all classes, b reaking capacity is based o n a circuit time constant of not less than 2 0 ms with
a re lative tolerance of +~%.

NOTE 5 An auxiliary contact which complies with class 1, 2 or 3 for d.c . is normally able to handle
corresponding a.c. current and voltage.
NOTE 6 Class 3 contacts are not intended to be subjected to ful! substation auxiliary supply short-circuit
current. Class 1 and 2 contacts are intended to be subjec ted to full substation auxiliary supply short-
circuit current .
NOTE 7 Bre aking current ata defined vo ltage value between 110 V and 250 V may be deduced from the
indicated power value for class 1 a nd class 2 contacts {for example 2 A at 220 V d.c. for a class 1 con tact)

The number of free auxi liary contacts and the c lass of each one sha ll be specified to the
ma nufacturer in accordance wit h clause 9 of the relevan! equipment sta nda rd. For particu la r
applications, different values may be spec ified to the manufacturer in accordance w ith
c lause 9 of the relevan! equipment standard.

Examples of the three contact classes are show n in figure 4.

+V

Class 2 Class 1

Relay Relay
J Power load

IEC 169112000

Figure 4 - Examples of classes of contacts

60694 © IEC:1996+A1:2000+A2:2001 -89-

5.4.4.5.5 Contacts other than auxiliary and control contacts

A contact other than an auxiliary or control contact is a contact driven by a componen! (relay,
contactor, low -voltage sw itch , etc.) used in the auxi liary and control circuits.

Where a contact other than an auxiliary or control contact is made available to the user, the
technica l documents provided by the manufacturer shou ld inc lude the rated continuous
curren! and making and breaking capacity of this contact.

The user is responsible for ensuring that the contact performance is adequate for the task.

The number of contacts provided shall be specified to the manufacturer in accordance w ith
clause 9 of the relevan! equipment standard.

5.4.4.5.6 Relays

All-or-nothing relays shall comply with the requirements of the applicable parts of IEC 6181 O.

IEC 61810-1 sets the recommended rated voltages for relays and the recommended limits of
the operating range for these voltages. For all relays chosen for the rated supply voltage
of the auxiliary and control c ircuits, the limits of the operating range in IEC 61810-1 allow the
relays to meet the limits required in 4.8.

Where a relay is chosen and used al a voltage different from the rated voltage of auxiliary and
control circuits, suitable means shall be provided to allow it to operate correctly w ithin the
limits of the operating range required in 4.8 (for example, provision of a series resistor).

Thermal electrical relays for motor protection shall comply with the requirements of IEC 60255-8.

Performance of relay contacts shall comply w ith the requirements of IEC 60255-23.

Requirements for relay contacts available to the user, if any, are contained in 5.4.4.5.5.

5.4.4.5.7 Contactors and motor-starters

AC and d.c. electromechanical contactors intended for closing and opening electric circuits
shall comply w ith the requ irements of IEC 60947-4-1. Where an electromechan ical contactor
is combined with suitable relays, to provide short-circuit protection , it shall also satisfy the
relevan! conditions for LV circuit-breakers, as specified in IEC 60947-2.

AC motor-starters intended to start and accelerate motors to normal speed , to ensure

continuous operation of motors, to sw itch off the supply from the motor and to provide means
for the protection of motors and associated circuits against operating overloads shall comply
w ith the requirements of IEC 60947-4-1. Overload relays for starters shall also meet the
requirements of I EC 6094 7-4-1.
60694 © IEC:1996+A1:2000+A2:2001 -91 -

AC semiconductor motor controllers and starters shall comply with !he requirements of
IEC 60947-4-2.

Requirements far contactar and motor-starter contacts available to !he user, if any, are
contained in 5.4.4.5.5.

5.4.4.5.8 Shunt releases

Shunt releases are designed far specific purposes. As no IEC standard exists far shunt
releases, they should satisfy !he requirements of !he relevan! equipment standard.

The electrical pow er of !he shunt releases shall be stated by !he manufacturer.

5.4.4.5.9 Low-voltage switches

Sw itches to be used in motor circuits shall comply with !he requirements of IEC 60947-3.

Sw itches to be used in distribution c ircuits or in final c ircuits shall comply w ith !he
requirements of I EC 6094 7-3.

Where household sw itches are applied in fina l circu its, they shall comply w ith !he
requirements of I EC 60669-1 .

Manual control sw itches , far example push-buttons , rotary sw itches , etc. shal l comply with !he
requirements of IEC 60947-5- 1. Suggesled colours far these sw itches are given in IEC 60073.
Suggested graphical symbols far use on eq uipment are given in IEC 60417. Where a user has
no specific local requirements, it is recommended that !he colouring and labelling of manual
control sw itches be in accordance w ith these tw o publications.

Requirements far any contacts of manual control sw itches that are made available to ! he user
are contained in 5.4.4.5.5.

Pilo! sw itches, far example pressure sw itches, temperature sw itches , etc. shall comply w ith
!he requirements of IEC 60947-5-1. Where household t hermostats are applied , they shall
comply w ith !he requirements of I EC 60730-2-9 that sets !he particular requirements far
automatic electrical temperature sensing co ntrols far household and similar use. Where
household humidily sensing controls are applied, they s hall comply with !he requirements of
IEC 60730-2-13, w hich sets !he particular requirements far automatic elect rical humidity
sensing controls far household and similar use. Requirements far any pilo! sw itch contacts
that are made available to !he user are c onta ined in 5.4.4.5.5.

Lever (togg le) sw itches shall comply w ith !he requirements of IEC 61020-4. Requirements far
any lever sw itch contacts that are made available to !he user are contained in 5.4.4.5.5.

5.4.4.5.1 O Low-voltage circuit-breakers

Low -voltage circu it-breakers shall comply w ith !he requirements of IEC 60947-2.

Low -voltage circuit-breakers incorporating residua l curren! protection shall also comply w ith
IEC 60947-2.
60694 © IEC:1996+A1:2000+A2:2001 - 93 -

5.4.4.5.11 Low-voltage fuses

Low -voltage fuses shall comply w ith the requirements of IEC 60269-1.

Supplementary requirements concerning fuses mainly for industria l application are covered by
IEC 60269-2. IEC 60269-2- 1 gives three examples of f use systems as standardized systems
w ith respect to their safety aspects.

5.4.4.5.12 Low-voltage disconnectors

Low -voltage disconnectors shall comply w ith IEC 60947-3.

5.4.4.5.13 Motors

Rotating electrical machines shall comply with the requirements of the applicable subclauses
of I EC 60034-1.

5.4.4.5.14 Heating elements

AII heating elements shall be of t he non-exposed type. Heaters shall be situated so that they
do not cause any deterioration in the wi ring or in the operation of the components.

Where contact w ith a heater or shield can occur accidentally, the surface temperature shall
not exceed the temperature-rise lim its for accessible parts w hich need not be touched in
normal operation, as specified in table 3.

5.4.4.5.15 Meters

Direct-acting indicating analogue e lectrical measuring instruments and their accessories shall
comply w ith the requirements of the applicable parts of IEC 60051. Ammeters and voltmeters
shall comply w ith the requirements of IEC 60051 -2. Frequency meters shall comply w ith the
requirements of IEC 60051-4. Phase meters, pow er factor meters and synchroscopes shall
comply with the requirements of IEC 60051 -5.

Digital electronic d.c. voltmeters and d .c. e lectronic analogue-to-digital converters shall
comply with the requirements of IEC 60485.

5.4 .4.5.16 Counters

Counters shall be suitable for their intended duty in terms of environmental conditions and for
t he number of electrical and mechanical operating cycles specified for the sw itching devices.

5.4.4.5.17 lndicator lights

lndicator lights are associated w ith the control circuí! equ ipment. Therefore, they sh all meet
t he requirements of I EC 6094 7-5-1 .

Suggested colours for indicator lights are given in IEC 60073. Suggested graphical symbols
for use on equipment are given in IEC 60417. W here a user h as no specific local
requirements, it is recommended that the colouring and labelling of any indicator lights be in
accordance w ith these tw o publications.

5.4 .4.5.18 Plugs, socket-outlets and couplers

Plugs and socket-outlets primarily intended for industrial use, either indoors or outdoors, shall
comply with the requirements of IEC 60309-1 and IEC 60309-2.
60694 © IEC:1996+A1:2000+A2:2001 -95-

Where a household socket-outlet is installed, it shall comply w ith the requirements of

IEC 60083 that sets the particular requirements for plugs and socket-outlets for domestic and
similar use .

Cable couplers primarily intended for industrial use, either indoors or outdoors, shall comply
w ith the requirements of IEC 60309-1 and IEC 60309-2.

Appliance couplers primarily intended for industrial use, either indoors or outdoors, shall
comply with the requirements of IEC 60309-1 and IEC 60309-2.

Other connectors shall comply w ith the requirements of the applicable parts of IEC 60130.

5.4.4.5.19 Printed boards

Printed boards used to connect conventional components (for example, relays) are consi-
dered to be conventional equipment. Printed boards shall comply w ith the requirements of the
applicable parts of IEC 60326.

5.4.4.5.20 Resistors

Fixed pow er resistors, rated over 1 W and under 1 000 W, shall comply w ith the requirements
of IEC 60115-4.

Potentiometers shall comply w ith the requirements of IEC 60393-1.

5.4.4.5.21 lllumination

In sorne enclosures , for example enclosures containing manual operating means (handles,
push-buttons, etc .), lighting should be considered. Where lighting is installed , consideration
should be given to the heat and electromagnetic noise produced by the lighting on the
auxiliary and control-circuit components.

Tungsten filament lamps shall comply w ith the requ irements of IEC 60064.

Fluorescent illumination shall comply w ith requirements of IEC 60081.

5.4.4.5.22 Coils

Coils not covered by a componen! standard sha ll be suitable for their intended duty
(for example, w ith respect to temperature rise, dielectric w ithstand, etc.).

5.4.5 Secondary systems

In many cases , the secondary system may be divided into a number of subassemblies , such
as the central control cubicle of a circuit-breaker, or the complete control cubicle of a circuit-
breaker in a gas-insulated substation (G IS ) bay. Examples are show n in figures 5, 6 , 7 and 8.

lnterchangeable subassemblies may be placed in difieren! position w ithin the secondary

system or replaced by other similar subassemblies.
NOTE In practice, there is a wide variation in the complexity of equipment within the secondary system. In sorne
cases the system may consist of only sorne a uxiliary all-or~nothing relays, signal cabling and terminal blocks.
In other cases, complete equipment for protection, con trol and measurement is included.
60694 © IEC:1996+A 1:2000+A2:2001 - 97-

A
,___
~:P
: r:o:lec::lion:::::::::::::'.~ B

~=M
=e=l=
en=·ng
:::::::::::::::~ B
Enclosure for secondary equipment
' -E
- l_c _ _ _ _ _ __ , ~ B

Circuit-breaker enclosure

._S
_e_n_s_o-----"~
rs 8

- lo_rs___~~ B
'-h- lua
IEC 169212000

A External interface, for total secondary system

8 Interna! interface, for subassembly

Figure 5 - Example of secondary system in medlum voltage cublcle

Operaling
mechanism

IEC 1693/2000

A Externa! interface, for total secondary system

NOTE Subassemblies may be defined within the cubicle in line with figure 5.

Figure 6 - Example of secondary system of alr lnsulated clrcult-breaker

with single mechanlsm
60694 © IEC:1996+A1:2000+A2:2001 -99-

Central control
B B B cubicle

Operating Operating Operating B A

mechanism mechanism mechanism

IEC 1694/2000
A External interface, for total secondary system
B Interna! interface, for subassembly
NOTE Subassembties may be defined within each cubicle in line with figure 5

Figure 7 - Example of secondary system of air insulated circuit-breaker

with separate control cubicle

Central control
cubicle

B
B A
¡sensors

IEC 1695í2000
A Extern a! interface, for total secondary system
8 Infernal interface, for subassembly
NOTE Subassembties may be defined within each cubicle in line with figure 5 .

Figure 8 - Example of secondary system for GIS bay

5.5 Dependen! power operation

A switching device arranged for dependen! power operation w ith externa! energy supply shall
be capable of making and/or breaking its rated short-circuit curren! (if any) when !he voltage
or !he pressure of !he pow er supply of the operating device is al !he lower of !he limits
specified under 4.8 and 4.1 O (!he term "o perating device" here embraces intermediate control
relays and contactors w here provided). lf maximum closing and opening t imes are stated by
! he manufacturer, these shall no! be exceeded.

Except for slow operation during maintenance, !he main contacts s hall only move under !he
action of !he drive mechanism and in !he designed manner. The closed or open position of !he
main contacts shall not change as a result of loss of the energy supply or the re-appl ication of
!he energy supply alter a loss of energy, to the closing and/ or opening device.
60694 © IEC:1996+A1:2000+A2:2001 - 101 -

5.6 Stored energy operation

A switching device arranged for stored energy operation sha ll be c apable of making and
breaking its rated short-circuit curren! (if any). when !he energy store is suitably charged in
accordance with 5.6.1 or 5.6.2. lf maximum closing and opening times are stated by !he
manufacturer, these shall no! be exceeded.

Except for slow operation during maintenance, the main contacts shall only move under the
action of the drive mechanism and in !he designed manner, and no! in the case of re-
application of !he energy supply after a loss of energy.

5.6.1 Energy storage in gas receivers or hydraulic accumulators

When the energy store is a gas recei ver or hydraulic accumulator, the requirements of 5.6
apply at operating pressures betw een the limits specified in items a) and b):

a) Externa! pneumatic or hydraulic supply

Unless otherwise specified by the manufacturer, the limits of the operating pressure are
betw een 85 % and 110 % of rated pressure.
These limits do not apply w here recei vers also store compressed gas for interruption.
b) Compressor or pump integ ral with !he switching device or !h e operating device
The limits of operating pressure shall be stated by !he manufacturer.

5.6.2 Energy storage in springs (or weights)

When !he energy store is a spring (or w eight), !he requ irements of 5.6 apply when !he spring
is charged (or !he weight lifted). lt shall no! be possible for !he moving contacts to move from
!he open position unless !he charge is suffic ient for satisfactory completion of !h e clos ing
operation.

5.6.3 Manual charging

lf a spring (or w eight) is charged by hand, the direction of motion of the handle shall be
marked. A device indicating when !he spring (or weight) is charged shal l be mounted on !he
sw itching device except in !he case of an independent manual closing operation.

The maximum actuating force required for manually charging a spring (or w eight) shall no!
exceed 250 N .

5.6.4 Motor charging

Motors, and their electrica lly operated auxiliary equipment for charging a spring (or w eight) or
for driving a compressor or pump, shall operate satisfactorily between 85 % and 11 O % of !he
rated supply voltage (see 4.8), the frequency, in the case of a .c., being the rated supply
frequenc y (see 4 .9).
NOTE For electric motors the limits do not imply the use of non-standard motors , but only the selection of a motor
which at these vatues provides the necessary effort , and the rated voltage of the motor need not coincide with the
rated supply voltage of the closing device.

In addition a means of charg ing a spring or w eight by hand shall be provided if sp ecified to
! he manufacturer; such means shall comply with 5.6.3.
60694 © IEC:1996+A1:2000+A2:2001 - 103 -

5.7 lndependent manual operation

In the case of an independent manually operated sw itch or earthing switch - if stated by the
manufacturer - to avoid the untimely reopening of the apparatus after c losing on a short
circuit, a defined time delay should be introduced between the closing and opening operation
by suitable means. This time delay shall be not less t han the rated duration of the short circuit
(see 4.7).

5.8 Operation of raleases

The operation limits of releases shal l be as follow s.

5.8.1 Shunt closing release

A shunt c losing release shall opera te correctly between 85 % and 11 O % of the rated supply
voltage of the closing device (see 4.8), the frequency, in the case of a.c ., being the rated
supply f requency of the closing device (see 4.9) .

5.8.2 Shunt opening release

A shunt opening release shall operate correctly under all operating conditions of the sw itching
device up to its rated short-circuit breaking curren!, and betw een 70 % in the case of d.c. -
or 85 % in the case of a.c. - and 11 O % of the rated supply voltage of the opening device
(see 4.8) , the frequenc y in the case of a.c. being the rated supply frequenc y of the open ing
device (see 4.9).

5.8.3 Capacitor operation of shunt raleases

When, for stored energy operation of a shunt release, a rectifier-capacitor combination is

provided as an integral part of the sw itching device, the charge of the capacitors to be derived
from the voltage of t he main circuit, the capacitors shall retain a charge sufficient for
satisfactory operation of the release 5 s after the voltage supply has been disconnected from
the terminals of the combination and replaced by a short-circuiting link. The voltages of the
main circuit before disconnection shall be taken as the low est voltage of the system
associated w ith t he rated voltage of the switching device (see I EC 60038 for the relation
between "highest voltage for equipment" and system voltages).

5.8.4 Under-voltage release

An under-voltage release shall operate to open t he sw itching device w hen th e voltage at the
terminals of the release falls below 35 % of its rated voltage, even if the fall is slow and
gradual.

On the other hand, it shall not operate the switching device when the voltage al its terminals
exceeds 70 % of its rated supply voltage.

The closing of the sw itching device shall be possible when the values of the voltage al the
terminals of the release are equal to or higher !han 85 % of its rated voltage. lts closing shall
be impossible w hen the voltage at the terminals is lower !han 35 % of its rated supply voltage.

5.9 Low- and high-pressure interlocking and monitoring devices

Where low -pressure or high-pressure interlocking dev ices a re provided in operating

mechanism systems, they shall be such that they can be set to operate at, or within , the
appropriate limits of pressure stated by the manufacturer, in accordance w ith 5.6.1 and w ith
relevan! IEC specifications.
60694 © IEC:1996+A1:2000+A2:2001 - 105 -

Closed pressure systems filled with compressed gas for insulation and/ or operation and
having a mínimum functiona l pressure for ins ulation and/or operation above 0,2 MPa
(absolute pressure), shall be provided w ith pressure (or density) monitoring devices, to be
continuously, or al leas! period ically, checked as part of the maintenance programme, taking
into account the relevan! IEC standards. For sw itchgear and controlgear having a mínimum
functional pressure not higher than 0 ,2 MPa (absolute pressure) , such means should be
subject to agreement between manufacturer and user.

5.1 O Nameplates

Sw itchgear and controlgear and their operating devices shall be provided w ith name-plates
w hich contain the necessary informat ion such as the name or mark of the manufacturer, the
year of manufacture, the manufactu rer's type designation, the serial number, the rated
characteristics etc. as specified in the relevan! IEC standards.

For outdoor sw itchgear and controlgear, the nameplates and their fixings shall be w eather-
proof and corrosion-proof.

lf the sw itchgear and controlgear consist of several poles with independent operating
mechanisms, each pole shall be provided w ith a nameplate.

For an operating device combined w ith a sw itching device, it may be sufficient to use only one
combined nameplate.

Technical c haracteristics on nameplates and/or in documents w hich are common to several

kinds of high-voltage sw itchgear and controlgear shall be represented by the same symbols .
Such characteristics and their symbols are:

- rated voltage u,
- rated lightning impu lse withstand voltage 1)

- rated sw itching impu lse withstand voltage 1)

- rated power-frequency withstand voltage 1 ) Ud

- rated normal curren! ,,
- rated short-time w ithstand curren! /k
- rated peak w ithstand curren! /p
- rated frequency f,
- rated duration of short circuit lk
- rated auxiliary voltage Ua
- rated fil ling pressure (dens ity) for insulation Pre (Pre)
- rated fil ling pressure (dens ity) for operation Prm (P,m)
- alarm pressure (density) for insulation Pae (Pae)
- alarm pressure (density) for operation Pam (Pam)
- mínimum functional pressure (density) for insulation Pme (Pme )
- mínimum functional pressure (density) for operation Pmm (Pmm )-

Other characteristics (such as type of gas or temperature class) being specialized shall be
represented by the symbols w hich are used in the relevan! standards.

1) Th e values to be used for nameplates are phase-to-earth values.

60694 © IEC:1996+A1:2000+A2:2001 - 107 -

5.11 lnterlocking devices

lnterlocking devices between different components of equipment may be required for reasons
of safety and convenience of operation (for example betw een a sw itching device and the
associated earthing sw itch ).

These interlocking devices shall be provided subject to agreement between manufacturer and
user.

Sw itching devices , the incorrect operation of w hich can cause damage or w hich are used for
assuring isolating distances , shall be provided w ith locking facilities as specified to the
manufacturer (for example , provision of padlocks ).

An interlocking device is a system made of components (it may contain mechanical parts ,
cables , contactors , coils, etc. ). Each componen! shall be considered as a part of auxiliary and
control equipment (see 5.4 ).

5.12 Position indication

Clear and reliable indication shall be provided of the position of the contacts of the main
circuit in case of non-vis ible contacts . lt shall be possible to easily check t he state of the
position-indicating device w hen operating locally.

The colours of the position-indicating device in the open , closed, o r, w here appropriate,
earthed pos ition shall be in accordance w ith IEC 60073.

The closed position shall be marked , preferably w it h a 1 (as per symbol 417-IEC-5007-a
of IEC 60417). The open position shall be marked, preferably with a O (as per s ymbol
417-IEC-5008-a of IEC 60417).

Alternatively, in the case of a multi-function dev ice, the positions may be marked w ith
graphical symbols for diagrams of IEC 60617.

5.13 Degrees of protection by enclosures

Degrees of protection according to IEC 60529 , shall be specified for all enclosures of high-
voltage switchgear and controlgear conta ining parts of the main circu it allowing penetration
from outside as w ell as for enclosures for appropriate low -voltage control and/or auxiliary
circuits and mechanical operating equipment of all high-voltage switchgear, controlgear and
sw itching devices.

The degrees of protection apply to the service condition of the equ ipment.

NOTE The degrees of protection may be diffe rent far other conditions such as maintenance , testing, e tc

5.13.1 Protection of persons against access to hazardous parts and protection

of the equipment against ingress of salid foreign objects

The degree of protection of persons provided by an enclosure against access to hazardous

parts of the main circuit, control and/or auxiliary circuits and to any hazardous moving parts
(other than smooth rotating shafts and slow ly moving linkages ) shall be indicated by means of
a designation specified in table 6.

The first characteristic numeral indicates the degree of protection provided by the enclosure
w ith respect to persons , as w ell as of protection of the equipment inside the enclosure against
ingress of salid foreign bodies.

lf only the protection against access to hazardous parts is requested or if it is higher than that
indicated by the first characteristic numeral , an add itional letter may be used as in table 6 .
60694 © IEC:1996+A 1:2000+A2:2001 - 109 -

T able 6 gives detai ls of objects wh ich w ill be "excluded" from the enclosure far each of t he
degrees of protection. The term "excluded" implies t hat salid foreign objects will not enter fully
t he enclosure a nd that a part of the body or an object held by a person, either will not enter
t he enclosure or, if it enters , that adequate clearance will be maintained and no hazardous
moving part will be touched .

5.13.2 Protection against ingress of water

No degrees of protect ion against harmful ingress of w ater as per the second characteristic
numeral of the IP-code is specif ied (sec ond characteristic numeral X).

Equ ipment far outdoor insta llation provided with addit ional prot ection features against rain
and other w eather conditions sha ll be specified by means of the supplementary lett er W
placed after the second characteristic numeral , or after the addit ion al letter, if any.

5.1 3.3 Protection of equipment against mechanical impact unde r no rmal

service conditions

Enclosures of enc losed switchgear and controlgear s ha ll be of sufficient mec hanical strength
(possible corresponding tests are specif ied in 6.7.2) .

Far indoor insta llation, the proposed impact level is 2 J .

Far outdoor installation without additional mechanical prot ection , higher impact levels may be
specified , subject t o an agreement betw een manufacturer and user.

Table 6 - Degrees of protection

Oeg ree of Protection against ingre ss Prote ction against access

prote ction of solid foreign bod ie s to hazardous pa rts

IP1XB Objects of 50 mm diameter and greater Access with a finger (test-finger 12 mm diameter,
80 mm long)

IP2X Objects of 12,5 mm diameter and greater Access with a finger (test-finger 12 mm diameter,
80 mm long)

IP2XC Objects of 12,5 mm diameter and greater Access with a tool (test-rod 2 ,5 mm diameter,
100 mm long)

IP2XD Objects of 12,5 mm diameter and greater Access with a wire (test-wire 1,0 mm diameter,
100 mm long)
IP3X Objects of 2,5 mm diameter and greater Access with a tool (test-rod 2 ,5 mm diameter,
100 mm long)

IP3XD Objects of 2,5 mm diameter and greater Access with a wire (test-wire 1,0 mm diameter,
100 mm long)

IP4X Objects of 1,0 mm diameter and greater Access with a wire (test-wire 1,0 mm diameter,
100 mm long)

IP5X Dust Access with a wire (test-wire 1,0 mm diameter,

100 mm long)
The ingress of dust is not totally prevented ,
but does not penetrate in a quantity or at a
location such that it can interfere with
satisfac tory operation of apparatus orto impair
safe ty

NOTE 1 The designation of the degree of protection corresponds to IEC 60529.

NOTE 2 111 tl1e c;c:1se uí IP5X c..:c:1le yu1y 2 uf 13 .4 u í IE C 60529 , is c:1µµ1ic..:c:1Ule

NOTE 3 lf only the protection against access to hazardous parts is concerned, the additional letter is used and
the flrst numeral is replaced by an X
60694 © IEC:1996+A1:2000+A2:2001 - 111 -

5.14 Creepage distances

IEC 60815 gives general rules that assist in choosing insulators w hich should give
satisfactory performance under polluted conditions.

The mín imum nominal creepage distance of an outdoor externa! ceramic or glass insu lator
situated betw een phase and earth, betw een phases or across the terminals of a pele of a
circuit-breaker ora sw itch , is determined by the relation:

lt = a 11 U, ko
w here
/¡ is the mínimum nominal creepage distance (mm) (see note 1) ;
a is the application factor selected in relation to the type of insulation according to table 7;
/1 is the mínimum nominal specific creepage distance according to table II of IEC 60815
(mm/kV) (see note 2);
U, is the rated voltage of the sw itchgear and controlgear;
ko is the correction factor dueto diameter (see 5.3 of IEC 60815).
NOTE 1 Far the actual cre epage distance , the specified manufacturing tole ranc es are applicable (see IE C 60273
a nd IEC 60233)
NOTE 2 Ratio of th e cre epage distance mea sured between phase a nd earth divided by Ur

Table 7 - Application factors fer creepage distances

Application to insulation Application factor

a
Between phase and earth 1.0

Betwee n phases ✓3
Across open contacts of a circuit- 1.0
breaker ora switch

NOTE 1 Switching devices that m ay be exposed to out-of-phase

conditions may need a somewhat longer creepage distance across the
open contacts. An application factor a = 1, 15 has been suggested far
such applications.
NOTE 2 Non-ve rtical insulators liable to be covered with melting
po11uted snow may require a longe r creepage distance

5.15 Gas and vacuum tightness

The follow ing specifications apply to all switchgear and controlgear w hich use vacuum or gas ,
other than air al atmosph eric pressure, asan insulating , combined insulating and interrupting ,
or operating medium. Annex E gives sorne information , examples and guidance fer tightness.

5.15.1 Controlled pressure systems fer gas

The tightness of controlled pressure systems fer gas is spec ified by the number of
replenishments per day (N) or by the pressure drop per day (óp ). The permissible values shall
be given by the manufacturer.

5.15.2 Closed pressure systems for gas

The tightness characteristic of a closed pressure system stated by t he manufactu rer shal l be
consisten! w ith a mínimum maintenance and inspection philosophy.
60694 © IEC:1996+A1:2000+A2:2001 - 113 -

The tightness of closed pressure systems for gas is specified by the relative leakage rate F,0 1
of each compartment ; standardized values are 1 % and 3 % per year.
NOTE These vatues can be used to calculate times between replenishments, T, outside extreme conditions of
temperature or frequency of operations.

The possible leakages between sub-assemblies having different pressures are also to be
taken into account. In the particular case of maintenance in a compartment w hen adj acent
compartments contain gas under pressure, the permissible gas leakage rate across partitions
should also be stated by the manufacturer, and the time betw een replenishments shall be not
less than one month.

Means shall be provided to enable gas systems to be safely replenished w hilst the equipment
is in service.

5.15.3 Sealed pressure systems

The tightness of sealed pressure systems is spec ified by their expected operating life.

The standard va lues are 20 years and 30 years.

5.16 Liquid tightness

The following specifications apply to all sw itchgear and controlgear w hich use liquids as
insulating , or combined insulating and interrupting , or control medium w ith or without per-
manent pressure.

5.16.1 Controlled pressure systems for liquid

The tightness of controlled pressure systems for liquid is specified by the number of
replenishments per day, N 1,q or by the pressure drop, t.p 1,q without replen ishment, both
caused by the leakage rate F 11q.

The permissible values shall be given by the manufacturer.

5.16.2 Closed pressure systems for liquid

The tightness level of closed pressure systems for liquid, pressurized or not, shall be
specified by the manufacturer.

5.16.3 Tightness levels for liquid

The tightness level for liquid shall be indicated by the manufacturer. A clear distinction shall
be made betw een interna! and externa! tightness.

a) total t ightness: no liquid loss can be detected;

b) relative tightness : slight loss is acceptable under the fol low ing cond itions:
the leakage rate , F 1,q shall be less than the permissible leakage rate, F p(liq);
the leakage rate, F 1,q shall not continuously increase w ith time or in the case of
switching devices , w ith number of operations ;
the liquid leakage shall cause no malfunction of the sw itchgear or controlgear, nor
cause any injury to operators in the normal course of their duty.

5.17 Flammability

The materials shall be chosen and the parts designed such that they retard the propagation of
any f lame resulti ng from accidental overheating in the switchgear and controlgear.
60694 © IEC:1996+A1:2000+A2:2001 - 115 -

5.18 Electromagnetic compatibility (EMC)

The secondary system shall be able to w ithstand electromagnetic disturbances, stated in 2.1,
w ithout damage or malfunction. Th is applies both under normal operation and under sw itching
conditions, including interruption of fault currents in the ma in circuit.

Two EMC severity classes are defined for interfaces or ports of secondary systems or
subassemblies:

normal EMC severity class:

interfaces or ports situated close to the primary, high-voltage system;
interfaces or ports intended for connection betw een cubicles w ithin a secondary
system;
reduced EMC severity class: interfaces or ports intended for connection only w ithin a
cubicle, not situated close to the primary, high-voltage system .

A complete secondary system may consist of parts belong ing to both classes. An example is
show n in figure 9.

Control cubicle
operafmg mee arnsm
Sub-
assembly
-
R
Sub-
assembly - N

Sub-
assembly -
R

N
N
Sub-
assembly
N

!EC 1696/2000

N Normal EMC severity class

R Reduced E MC severity class

Figure 9 - Example of choice of EMC severity class

NOTE General guidance regarding EMC and considerations to improve EMC are given in IEC 61000-5-1 and
IEC 61000-5-2. The magnitude of induced voltages in a secondary system depends both on the secondary system
itself and on conditions such as the earthing and rated voltage of the main circuit.

6 Type tests

6.1 General

The t ype tests are for the purpose of proving t he characteristics of switchgear and
controlgear, their operating devices and their auxiliary equipment.

6.1.1 Grouping of tests

The t ype tests shall be carried out on a maximum of four test specimens unless otherwise
specified in the relevan! IEC standards.
NOTE The rat ionate behind the spec ification of tour test specimens is to give increased confidence to users that
t he switchgear and controlgear tested is representative of that which will be delivered (in the limit, this would
require all tests to be carried out on a single specimen), whilst allowing m anufacturers to carry out testing at
separate laboratories for d ifferent groups of tests.
60694 © IEC:1996+A1:2000+A2:2001 - 117 -

Each test spec imen of sw itchgear and controlgear shall truly conform to drawings and be fully
representative of its type and shall be subjected to one or more type tests.

For convenience of testing , the type tests may be grouped. An example of a possible grouping
is show n in table 8 below .

Table 8 - Example of grouping of type tests

Group Type tests Subclause

1 Dielectric tests on main, auxilia ry and control circuits 6.2
Radio inte rfe rence voltage (r.i.v.) test 6.3
2 Measurement of resistance of the main curre nt path 6 .4
Tempera ture rise tes ts 6.5
3 Short~time withstand curre nt an d peak withstand curren t tests 6.6
Making and breaking tests See re le vant IEC sta ndard

4 Tests to verify the degrees of protection of enclosures 6.7

Tightness tests (wh ere applicable) 6.8
Mechanica l tests

Environmental tests
} See releva nt IEC sta ndard

W here additional type tests are necessary, these are specified in the relevan! IEC standard.

Each individua l type test sha ll be made in principie on complete sw itchgear and controlgear
(but see 3.2.2) in the condition as required for service (filled w ith t he specified types and
quantities of liquid or gas at specified pressure and temperature) , on their operating devices
and auxiliary equipment, all of which in principie shall be in, or restored to, a new and clean
condition al the beginning of each type test.

Recondition ing during individual type tests may be allow ed, acc ording to the relevan! IEC
standard. The manufacturer shall provide a statement to the testing laboratory of those parts
that may be renew ed during the tests.

6.1.2 lnformation for identification of specimens

The manufacturer shall submit to the testing laboratory, draw ings and other data containing
sufficient information to unambiguously identify by type the essentia l details and parts of the
sw itchgear and controlgear presented for test. Each draw ing or data schedule shall be
uniquely referenced and shall contain a statement to the effect that the manufacturer
guarantees that the drawings or data schedules truly represen! the sw itchgear and
controlgear to be tested .

After completion of verification, detail draw ings and other data shall be returned to the
manufacturer for storage.

The manufacturer shall maintain detailed design records of all componen! parts of the
sw itchgear and controlgear tested and shall ensure that these may be identified from
information included in the draw ings and data schedules.

NOTE Manufacturers whose production systems have been certified far compliance with ISO 9001 or ISO 9002 do
satisfy the previously rnentioned req uirements.

The testing laboratory shall check that draw ings and data schedules adequately represen! the
essential details and parts of the sw itchgear and controlgear to be tested , but shall not be
responsible for the accuracy of the detailed information.
60694 © IEC:1996+A1:2000+A2:2001 - 119 -

Particular drawings or data required to be subm itted by the manufacturer to the test laboratory
for identification of essential parts of switchgear and controlgear are spec ified in annex A.
NOTE An individual type test need not be re peated for a change of construction detail, if the ma nufa cturer can
demonstrate that this change does not influe nce the result of that individual type test .

6.1.3 lnformation to be included in type-test reports

The results of all type-tests shall be recorded in type-test reports containing sufficient data to
prove compliance w ith the specification , and sufficient information shall be included so that
the essentia l parts of the sw itchgear and controlgear can be identified. In particular, the
following information shall be included:

- manufacturer;
- type designation and serial numbe r of sw itchgear and controlgear tested ;
- rated characteristics of sw itchgear and controlgear tested as spec ified in the relevan! IEC
standard;
- general description (by manufacturer) of sw itchgear and controlgear tested, including
number of poles;
make , type, serial numbers and ratings of essential parts , w here applicable (e.g.
operating-mechanisms , interrupters , shunt impedances);
- general details of the supporting structure of t he sw itching device or enclosed sw itchgear
of w hich t he switching device forms an integral part ;
- details of the operating-mechanism and devices employed during tests , w here applicable;
photographs to illustrate the condition of sw itchgear and controlgear before and alter test ;
- sufficient outline draw ings and data schedu les to represen! the sw itchgear and controlgear
tested ;
- reference numbers of all drawings submitted to identify the essential parts of the
sw itchgear and controlgear tested;
- details of the testing arrangements (including diagram of test c ircuit);
- statements of the behaviour of the sw itchgear and controlgear during tests , its condition
alter tests and any parts renew ed or recondition ed during th e tests;
- records of the test quantities during each test or test duty, as specified in the relevan! IEC
standard.

6.2 Dielectric tests

Dielectric tests of the switchgear and controlgear shall be performed in compliance w ith
IEC 60060-1 , unless otherwise specified in th is standard.

lnformation about dielectric tests is given in annex F.

NO T E W here switchgear and controlgear incorporal es voltage- limiting devices which cannot be separated from
the switchgear and control gear, then the complete equipment should be tested in accordance with annex F.

6.2.1 Ambient air cond itions during tests

Reference shall be made to IEC 60060-1 regarding standard reference atmospheric conditions
and atmospheric correction factors .

For sw itchgear and controlgear w here externa! insulation in free air is of principal concern , the
correction factor K 1 shall be applied.
60694 © IEC:1996+A1:2000+A2:2001 - 121 -

The humidity correction factor shall be applied only for the dry tests w here insulation in free
air is of principal concern .

For switchgear and controlgear of rated voltage of 52 kV and below , it can be assumed that:

m =
1 and w =O w hen !he absolute humidity is h igher t han that of the reference
3
atmosphere, i.e. w hen h > 11 g/ m ;
m =
1 and w =1 when the absolute humidity is low er than that of the reference
3
atmosphere, i.e. w hen h < 11 g/ m .

For sw itchgear and controlgear having externa! and interna! insulation, the correction factor K 1
shall be applied if its value is betw een 0,95 and 1,05. How ever, in order to avoid over-
stressing of interna! insulation, the application of t he correction fa ctor K1 may be omitted
w here the satisfactory performance of externa! insulation has been established. W hen the
correction factor is outside the range of 0 ,95 and 1,05, detai ls of dielectric tests shall be
subject to agreement betw een manufacturer and user.

For switchgear and controlgear having only interna! insulation , !he ambient air conditions are
of no influence and !he correction factor K1 shall not be applied.

For combined tests , parameter g shall be calculated considering the total test vo ltage v alue.

6.2.2 Wet test procedure

The externa! insulation of outdoor switchgear and controlgea r shall be subjected to wet
w ithstand tests under the standard w et test procedure given in IEC 60060-1.

6.2.3 Conditions of switchgear and controlgear during dielectric tests

Dielectric tests shall be made on sw itchgear and controlgear completely assembled , as in

service; the outside surfaces of insulating parts sha ll be in clean cond ition.

The sw itchgear and controlgear shall be mounted for test w ith m ínimum clearances and height
as specified by the manufacturer.

Equ ipment tested al one height above ground surface level w ill be deemed to be satisfactory
if mounted ata greater height above ground surface level w hen in service.

When !he distance betw een the poles of switchgear and controlgear is no! inherently fixed by
!he design , the distance betw een the poles for the test shall be the mínimum value stated by
!he manufacturer . However, to obviate the necessity of erecting large t hree-pole sw itchgear
and controlgear for test purposes alone , !he artificial pollution and !he radio interference
v oltage tests may be made on a single pole and , if !he mínimum clearance betw een poles is
equal to or larger !han !hose given in tables F. 1 and F.3 of IEC 60071-2, all other dielectric
tests may be made on a single pole.

When !he manufacturer states that supplementary insulation such as tape or barriers is
required to be used in service , such supplementary insu lation shall also be used during !he
tests.

lf arcing horns or rings are required for !he purpose of system protection, they may be
removed or their spac ing increased for the purpose of !he test. lf they are required for
gradient d istribution, they shall remain in position for the test .
60694 © IEC:1996+A1:2000+A2:2001 - 123 -

Far sw itchgear and controlgear using compressed gas far insu lation, dielectric tests shall be
perfarmed al mínimum functional pressure (density) far insulation as specified by the
manufacturer. The temperature and pressure of t he gas during the tests sh all be noted and
recorded in the test report.
NOTE Caution: In the dielectric testing of switchgear an d controlgea r incorporating vacuum switching devices,
precautions should be taken to ensure that the level of possible emitted X-radiation is within safe limits. National
safety codes may influence the safety measures established.

6.2.4 Criteria to pass the test

a) Short-duration pow er-frequency w ithstand voltage tests

The sw itchgear and controlgear shall be considered to have passed the test if no
disruptive discharge occurs.
lf during a w et test a disruptive discharge on externa! self-restoring insulation occurs, this
test shall be repeated in the same test condition and the sw itchgear an d controlgear shall
be cons idered to have passed this test successfully if no further disruptive discharge
occurs.

b) Impulse tests
Procedure B of IEC 60060-1 shall be applied: 15 consecutive lightning or sw itching
impulses at the rated w ithstand voltage shall be applied far each test condition and each
polarity. The sw itchgear and controlgear shall be considered to have passed the test if the
number of the disruptive discharges on self-restoring insulation does not e xceed tw o far
each series of 15 impulses and if no disruptive discharge on non-self-restoring insulation
occurs.
Procedure C of IEC 60060-1 may be applied as an alternative to the 15 impulses
withstand test. In this case, the test shall be performed by applying t hree consecutive
impulses far each polarity. The sw itchgear and controlgear shall be considered to have
passed the test if no disruptive discharge occurs. lf one disruptive discharge occurs in the
self-restoring par! of the insulation , then 9 additional impulses shall be applied and if no
disruptive discharges occur, the sw itchgear and controlgear shall be considered to have
passed the test.
lf it is preved that tests far one polarity g ive the most unfavourable results, it is
permissible to perfarm the tests far this polarity only.
Sorne insulating materials retain a charge after an impulse test and far these cases care
should be taken w hen reversing the polarity . To allow t he discharge of insulat ing
materials , the use of appropriate methods, such as the application of three impulses at
about 80 % of the test voltage in the reverse polarity befare the test, is recommended.

c) General comment
W hen testing large sw itchgear and controlgear, the par! of equipment through w hich the
test voltage is applied may be subjected to numerous test sequences to check the
insulating properties of other dow nstream parts of equipment (circuit-breakers ,
disconnectors, other bays). lt is recommended that parts be tested in sequence , starting
with first connected part. W hen this part has passed the test according to the above-
mentioned criteria , its qualification is not impaired by possible disruptive discharges w hich
could occur in it during further tests on other parts.
NOT E These discharges may have been ge nerated by accumulation of discharge probability with the
increased number of volta ge applications or by reflected voltage after a disruptive discha rge at a remate
location within the equipment. To reduce the probability of occurrence of these discharges in ga s-filled
equipment, the pressure of the alrea dy-tested parts may be increased after passing their tests.
60694 © IEC:1996+A1:2000+A2:2001 - 125 -

6.2.5 Application of the test voltage and test conditions

Distinction must be made betw een the general case, where the three test voltages (phase-to-
earth, between phases and across open sw itching device) are the same, and the special
cases of the isolating distance and of insulation between phases higher than phase to ground.

6.2.5.1 General case

With reference to figure 2, w hich show s a diagram of connection of a three-pole switching

device, the test voltage shall be applied according to the follow ing table 9:

Table 9 - Test conditions in general case

Test condition Switching device Voltage applied to Earth connected to

1 Closed Aa BCbcF
2 Closed Bb ACacF

3 Closed Ce ABabF

4 Open A BCabcF
5 Open B ACabcF

6 Open e ABabcF
7 Open a ABCbcF
8 Open b ABCacF
9 Open e ABCabF

Test conditions 3, 6 and 9 may be omitted if the arrangement of the outer peles is symmetrical
with respect to the centre pele and the trame. Test conditions 7, 8 and 9 may be omitted if the
arrangement of the terminals of each pele is symmetrical w ith respect to the base.

6.2.5.2 Special case

When the test voltage across the open switching device is higher than the phase-to-earth
w ithstand voltage , different test methods may be used.

a) Preferred method
Unless otherwise specified in this standard, the preferred method is the use of combined
voltage tests (see clause 26 of IEC 60060-1 ).
Pow er-frequency voltage tests
The tests shall be performed using two different voltage sources in out-of-phase
conditions in order to obtain the specified test value. The voltage share is specified
in 6.2.6.1 and in 6.2. 7.1.
In this case, the test voltage across the open switching device (or isolating distance)
shall be applied according to the following table 1O.

Table 1O - Power-frequency test conditions for longitudinal insulation

Test condition Voltages applied to Earth connected to

1 A anda BCbcF
2 B and b ACacF
3 e ande ABabF

Test conditions 3 may be omitted if the arrangement of the outer peles is symmetrical
with respect to the centre pele and the trame.
60694 © IEC:1996+A1:2000+A2:2001 - 127 -

Impulse voltage tests

The rated impulse withstand voltage phase-to-earth constitutes the main par! of the
test voltage and is applied to one terminal; the complementary voltage is supplied by
another voltage source of the oppos ite polarity and applied to the opposite terminal.
This complementary voltage may be either another impulse voltage or the peak of a
power-frequency voltage. The other poles and t he trame are eart hed.
To take into account the influence of the impu lse on the pow er-frequency voltage
w a ve, caused by capac itive coupling between the tw o voltage c ircuits, the following
test requirements shall be fulfilled: the voltage drop on t he pow er-frequency w ave shall
be limited so that the actual test voltage to ground, measured al the instan! of the peak
value of the impulse is not less than the value specified for the complementary voltage
with a tolerance of 5 %. To achieve such a condition , the instantaneous power-
trequency voltage may be increased up to, but no more than U, .fi./
..fi for the
lightning impulse tests, and not more !han 1,2 U, .fi./ ✓3 for the sw itching impulse
tests. See D.2.3.1.
The voltage drop can be greatly reduced by using a capacitor of a convenient value
connected in parallel to the terminal of the power-frequency side.
The test voltage shall be applied according to table 11.

Table 11 - Impulse test conditions for longitudinal insulation

Test condition Main part Complementary part Earth connected to

Voltage applied to

1 A a BbCcF
2 B b AaCcF

3 e e AaBbF
4 a A BbCcF
5 b B AaCcF

6 e e AaBbF

Test conditions 3 and 6 may be omitted if the arrangement of the outer poles is
symmetrical w ith respect to t he centre pole and the trame.
Test conditions 4, 5 and 6 may be omitted if the arrangement of the terminals of each
pole is symmetrica l w ith respect to the trame.
b) Alternative method
When only one voltage source is used, the insulation across the open sw itching device (or
isolating distance) may be tested as follows , for both pow er-trequency voltage tests and
impulse voltage tests:
the total test voltage Ut is applied between one terminal and earth ; the opposite
terminal is earthed:
When t he resulting voltage across the supporting insulation of the sw itching device
w ould exceed the rated phase-to-earth w ithstand voltage , the trame is fixed al a partial
voltage w ith respect to earth U1, so that Ut - U1 is between 90 % and 100 % of the
rated withstand voltage phase-to-earth.
60694 © IEC:1996+A1:2000+A2:2001 - 129 -

6.2.6 Tests of switchgear and controlgear of u, s 245 kV

The tests shal l be performed w ith the test vo ltages given in table 1a or 1b.

6.2.6.1 Power-frequency voltage tests

Switchgear and controlgear shall be subjected to short-duration pow er-trequency voltage

w ithstand tests in accordance w ith IEC 60060-1. The test voltage shall be raised tor each test
condition to the test value and maintained for 1 min.

The tests shall be performed in dry conditions and also in w et conditions for outdoor
sw itchgear and controlgear.

The isolating distance may be tested as tollows:

- preterred method. In this case. neither ot the tw o voltage values applied to the tw o
terminals shall be less than one-third ot the rated w ithstand voltage phase-to-earth ;
- alternative method: for metal-enclosed gas-insulated switching device with a rated voltage
of less than 72,5 kV and for conventional sw itching device ot any rated voltage, the
voltage to earth ot the frame U1 need not be fixed so accurately and the trame may even
be insulated.
NOTE Due to the large scatter of the results of power-frequency voltage wet tests for switchgear and controlgear
of rated voltage equal to 170 kV and 245 kV, it is accepted to replace these tests by a wet 250/2 500 ocs switching
impulse voltage test, with a peak value equal to 1,55 t imes the r. m.s. value of the specified power-frequency test
voltage

6.2.6.2 Lightning impulse voltage tests

Sw itchgear and controlgear shall be subjected to lightn ing impulse voltage tests in dry
conditions only. The tests shall be performed w ith voltages of both polarities using the
standard lightn ing impulse 1 ,2/50 ocs according to IEC 60060-1.

When the alternative method is used to test the isolating distance ot metal-enclosed gas-
insulated switching device w ith a rated vo ltage ot less than 72 ,5 kV and ot conventional
sw itching device ot any rated voltage , the voltage to earth of the trame U1 need not be fixed
so accurately and the trame may even be insulated.

6.2.7 Tests of switchgear and controlgear of rated voltage above 245 kV

In the closed pos ition, the tests shall be performed in conditions 1, 2 and 3 ot table 9. In the
open position , the tests shall be pertormed as stated below (but see 6.2.3). In addition,
phase-to-phase switching impulse voltage tests shall be pertormed as stated below. The test
voltages are given in table 2a or 2b.

6.2.7.1 Power-trequency voltage tests

Sw itchgear and controlgear shall be subjected to short-duration pow er-frequency voltage

w ithstand tests in accordance w ith IEC 60060-1. The test voltage shall be raised for each test
condition to the test value and maintai ned for 1 min.

The tests shal l be performed in dry conditions only.

The insulation across the open sw itch ing device or isolating distance shall be tested w ith the
preferred method a) of 6.2.5.2 above. Subjec t to agreement w ith t he manufacturer, the
alternative method b) ot 6.2.5.2 may also be used. W hichever method is chosen, neither ot
t he voltages applied between one terminal and the frame shall be higher than the rated
voltage u,.
60694 © IEC:1996+A1:2000+A2:2001 - 131 -

6.2.7.2 Switching impulse voltage tests

Switchgear and controlgear shall be subjected to sw itching impulse voltage tests. The
tests shall be performed w ith voltages of both polarities using the standardized sw itching
impulse 250/2500 ocs accord ing to IEC 60060-1. Wet tests shal l be performed for outdoor
switchgear and controlgear only.

The isolating distance shall be tested w ith the preferred method a) of 6.2.5.2.

The insu lation between pales shall be tested in dry conditions only w ith a total test voltage as
per column 5 of tables 2, by the preferred method a) of 6.2.5.2 above in which the tw o voltage
components should be equal to ha lf the total test voltage.

The actual voltage share shall be as balanced as possible. Any unbalanced share of !he total
test voltage is more severe. When voltage components are different in shape and/or
amplitude , the test shall be repeated reversing the connections.

6.2.7.3 Lightning impulse voltage tests

Sw itchgear and controlgear shall be subjected to lightn ing impulse voltage tests in dry
conditions only. The tests shall be performed w ith voltages of both polarities using the
standard lightn ing impulse 1 ,2/50 ocs according to IEC 60060-1.

6.2.8 Artificial pollution tests

No artificial pollution tests are necessary w hen the creepage distances of the insulators
comply with the requirements of 5. 14.

lf the creepage distances do not comply w ith the requirements of 5.14, artific ial pollution tests
should be performed according to IEC 60507 , using the rated voltage and the application
factors given in 5.14.

6.2.9 Partial discharge tests

When requested by the relevan! product standard , partial discharge tests shall be performed
and the measurements made according to IEC 60270.

6.2.10 Dielectric tests on auxiliary and control circuits

Auxiliary and control circu its of switchgear and controlgear shall be subjected to impulse
voltage w ithstand tests as well as to short duration pow er frequency voltage w ithstand tests.
Each test shall be performed:

a) betw een the auxiliary and control circuits connected together as a whole and the frame of
the sw itching device;
b) if practicable, between each part of the auxiliary and control circuits, w hich in normal use may
be insulated from the other parts, and the other parts connected together and to the frame.

The impulse voltage w ithstand tests shall be performed in accordance w ith IEC 60255-5.
The impulse voltage peak value shall be 5 kV. The auxiliary and control circuits shall
w ithstand !he tests w ithout permanent damage. After !he tests, they shall still be f ully
operational.

The pow er frequency tests shall be performed according to IEC 61180-1 . The test voltage
shall be 2 kV w ith a duration of 1 min.

The auxiliary and control c ircuits of sw itchgear and controlgear shall be considered to have
passed the tests if no disruptive discharge occurs during each test.
60694 © IEC:1996+A1:2000+A2:2001 - 133 -

Normally, !he test voltage of motors and other devices used in !he auxiliary and control
circuits shall be !he same as !he test voltage of !hose circuits. lf such apparatus has already
been tested in accordance w ith !he appropriate specification, it may be disconnected far these
tests. Low er test voltage values are under consideration far auxiliary components. lf it can be
v erified that !he dielectric stress permits it, low er voltage values may be used , by agreement
between manufacturer and user.

NOTE Possible lower values are 2 ,5 kV far the impulse test a nd 1 kV far the power frequency test

The selection criterion is based on the magnitude of the largest common mode voltage, al
industrial frequency, expected to occur between two points of !he earthing circuit ry of !he
substation (far example, during a primary short circuit or dueto !he presence of a shunt reactor).

6.2.11 Voltage test as condition check

W hen !he insulating properties across open contacts of a switching device after !he making ,
breaking and/or mechanical/electrical endurance tests cannot be verified by visua l inspection
w ith sufficient reliability, a pow er-frequency w ithstand voltage test in dry condit ion according
to 6.2.6.1 and 6.2.7. 1 across the open switching device at the fal low ing value of pow er-
frequenc y voltage may be appropriate.

Far equipment w ith rated voltages up to and including 245 kV :

80 % of !he value in table 1a or 1 b, column 3 far disconnectors and sw itch-disconnectors

(equipment w ith safety requirements) and column 2 far other equipment.

Far equipment w ith rated voltages from 300 kV and above:

100 % of the value in table 2a or 2b, column 3 far disconnectors and sw itch-disconnectors
(equipment w ith safety requirements):
80 % of !he value in tables 2a or 2b, column 3 far other equipment.
NOTE 1 The red uction of the test voltage is motivated by the safety margin in the rated test voltage values, which
takes ageing, wear and othe r normal deterioration into account, and by the statistica t nature of the flashover
voltage
NOTE 2 Condition-checking tests of the insulation to earth may be required far enclosed devices of certain
design_ In such cases a power-frequ ency test with 80 % of the va tues in column 2 , of tables 1 and 2 , respectively,
should be performed
NOTE 3 The relevant apparatus standard can specify that this condition-checking test is mandatory far certain
types of equipment

6.3 Radio interference voltage (r.i.v.) test

These tests apply only to sw itchgear and controlgear h av ing a rated voltage of 123 kV and
above, and shall be made w hen specified in !he relevan! IEC standards . Sw itchgear and
controlgear shall be installed as stated in 6.2.3.

The test voltage shall be applied as follow s:

a) in closed position, between the terminals and !he earthed f rame ;

b) in open position, betw een one terminal and !he other terminals connected to the earthed
frame and then w ith t he connections reversed if !he switching device is not symmetrical.

The case, tank, frame and other normally earthed parts shall be connecled to earth. Care
should be taken to avoid influencing !he measurements by earthed or unearthed objects near
to !he sw itchgear and controlgear and to !he test and measuring circuits.
60694 © IEC:1996+A1:2000+A2:2001 - 135 -

The switchgear and controlgear shall be dry and clean and al approximately the same
temperature as the room in which the test is made. lt should not be subj ected to other
dielectric tests w ithin 2 h prior to the present test.

The test connections and their ends shall not be a source of radio interference v oltage of
higher values !han !hose indicated below.

The measuring circuit (see figure 3) shall comply w ith CISPR 18-2. Th e measuring circuit
shall preferably be tuned to a frequency w ithin 1O % of 0,5 M Hz, but other frequencies in the
range 0,5 MHz to 2 MHz may be used, the measuring frequency being recorded. The results
shall be expressed in microvolts.

lf measuring impedances different from !hose specified in CISPR publications are used , they
shall be not more !han 600 O nor less ! han 30 O , in any case the phase angle shall not
exceed 20º . The equiv alen! radio interference voltage referred to 300 O can be calculated ,
assuming the measured voltage to be directly proportional to the resistance, except for test
pieces of large capacitance, for which a correction made on this basis may be inaccurate.
Therefore , a 300 O resistance is recommended for switchgear and controlgear w ith bushings
w ith earthed flanges (e.g. dead tank sw itchgear and controlgear).

The filler F shall have a h igh impedance al the measuring frequency, so that the impedance
between the high-voltage conductor and earth is not apprec iably shunted as seen from the
sw itchgear and controlgear under test. This fi ller also reduces circulating radio-frequency
c urrents in the test circuit, generated by the high-voltage transformer or picked up from
extraneous sources. A suitable value for its impedance has been found to be 10 000 O to
20 000 O al the measuring frequency.

11 shall be ensured by suitable means that the radio interference background level (radio
interference level caused by externa! field and by the h igh-voltage transformer w hen
magnetized at the full test voltage) is al leas! 6 dB and preferably 10 dB below the specified
radio interference level of the switchgear and controlgear to be tested. Calibration methods
for the measuring instrument and for the measuring c ircuits are given in CISPR 16-1 and
C ISPR 18-2 respectively.

As the radio interference level may be affected by fibres or dust settling on the insulators, it is
permitted to w ipe t he insu lators with a clean cloth before taking a measurement. The
atmospheric conditions during the test shall be recorded. lt is not known w hat correction
factors apply to radio interference testing but it is know n that tests may be sensitiv e to high
relative humidity and the results of the test may be open to doubt if the rela tive humidity
exceeds 80 %.

The follow ing test procedure shall be follow ed:

A voltage of 1, 1u, / ✓ 3 shall be applied to the sw itchgear and controlgear and maintained for
at least 5 m in, u, being the rated voltage of the switchgear and controlgear. The voltage shall
then be decreased by steps dow n to 0 ,3 U,/✓3, raised again by steps to the initial v al u e and
finally decreased by steps to 0,3 U,/ ✓ 3 . Al each step a radio interference measurement shall
be taken and the radio interference lev e!, as recorded during the last series of voltage
reductions, shall be plotted versus the appl ied voltage; the curve so obtained is the radio
interference characteristic of the sw itchgear and controlgear. The amplitude of voltage steps
shall be approximately O,1 u,/ ✓3.
60694 © IEC:1996+A1:2000+A2:2001 - 137 -

The switchgear and controlgear sha ll be considered to have passed !he test if !he radio
interference level al 1, 1 ✓ U, /
3 does no! exceed 2 500 "-V .

6.4 Measurement of the resistance of circuits

6.4.1 Main circuit

A measurement of !he resistance of !he main circuit shall be made for comparison betw een
! he switchgear and controlgear type tested for temperature rise and all other switchgear and
controlgear of !he same type subjected to routine tests (see 7.3).

The measurement shall be made wit h d.c. by measuring the voltage drop or resistance across
!he terminals of each pole. Special consideration shall be given to enclosed switchgear and
controlgear (see !he relevan! standards).

The curren! during !he test shall have any convenient value betw een 50 A and the rated
normal curren!.
NOTE Experience shows that an increase of the main circuit resistance cannot alone be considered as reliable
evidence of bad contacts or connections_ I n such a case, the test should be repeated with a higher current, as
clase as possible to the rated normal current

The measurement of the d .c. voltage drop or the resistance shall be made before the
temperature-rise test, with !he switchgear and controlgear at !he ambient air temperature and
alter the temperature-rise test when the switchgear and controlgear has cooled to a
temperature equal to ! he ambient air temperature. The measured resistances in these tw o
tests shall not differ by more than 20 % .

The measured value of the d.c . voltage drop or the resistance shall be given in t he type-test
report, as w ell as the general conditions during the test (curren!, ambient air temperature ,
points of measurement, etc.).

6.4.2 Auxiliary circu its

6.4.2.1 Measurement of the resistance of auxiliary contacts class 1 and class 2

One sample of each type of class 1 and class 2 auxiliary contacts shall be inserted into a
res istive load circuit through w hich flows a curren! of 1O mA w hen energised by a source
O
having an open circuit voltage of 6 V d.c . w ith a relative tolerance of % and the resistance
- 15
measured according to test 2b of IEC 60512-2.

The resistance of the closed class 1 and class 2 auxiliary contacts shal l not exceed 50 O.

NOTE On contact materials, oxidation may occur which decreases the effective current-carrying capabilities. This
results in an increased contact res istance or even no conduction at very low voltage while no problems are
observed at higher volt age. This test is intended to verify the contact performance under these low-voltage
conditions. The assessment criterion takes into account the non-linearity of the resistance. The 50 O value resu lts
from statistical considerations and has already been taken into account by users.

6.4.2.2 Measurement of the resistance of auxiliary contacts class 3

One sample of class 3 auxiliary contacts shall be inserted into a resistive load circuit through
w hich f lows a curren! S1 O mA w hen energized by a source havi ng an open circuit voltage
530 mV d.c. and the resistance measured accord ing to IEC 61810-7.

The resistance of !he closed class 3 auxiliary contacts shall not exceed 1 O.
60694 © IEC:1996+A1:2000+A2:2001 - 139 -

6.5 Temperature-rise tests

6.5.1 Conditions of the switchgear and controlgear to be tested

Unless otherwise specified in the relevan! standards , the temperature-rise test of the main
circuits shall be made on a new switch ing device w ith clean contacts , and , if applicable, filled
w ith the appropriate liquid or gas al the mínimum functional pressure (or density) far
insulation prior to the test.

6.5.2 Arrangement of the equipment

The test shall be made indoors in an environment substantially free from air currents, except
!hose generated by heat from the switching device being tested. In practice, this condition is
reached w hen the air velocity does not exceed 0,5 mi s.

Far temperature-rise tests of parts other than aux iliary equ ipment, the switchgear and
controlgear and their accessories shall be mounted in all significan! respects as in service ,
including all normal covers of any par! of the switchgear and controlgear, and shall be
protected aga inst undue external heating or cooling.

When the switchgear and controlgear, according to the manufacturer's instructions, may be
installed in different positions , the temperature-rise tests shall be made in the most
unfavourable position.

These tests shall be made in principie on three-pole switchgear and controlgear but may be
made on a single pole or on a single unit provided the influence of the other pales or units is
negligible. This is the general case far non-enclosed switchgear. Far three-pole switchgear
and controlgear with a rated normal curren! not exceeding 630 A , the tests may be made w ith
all pales connected in series.

Far switchgear and controlgear, particularly large switchgear and controlgear far which the
insulation to earth has no significan! influence on temperature rises, this insulation may be
appreciably reduced.

Temporary connections to the main circuit shall be such that no significan! amount of heat is
conducted aw ay from, or conveyed to, the switchgear and controlgear during the test. The
temperature rise at the terminals of the main circuit, and al the temporary connections al a
distance of 1 m from the terminals, sha ll be measured. The difference of temperature rise
shall not exceed 5 K. The type and sizes of the temporary connections shall be recorded in
the test report.

NOTE 1 To make the temperature-rise test more reproducible, the type and/or sizes of the temporary connections
may be specified in relevant standards.

Far three-pole switchgear and controlgear, the test shall be made in a three-phase c ircuit w ith
the exceptions mentioned above.

The test shall be made at the rated normal curren! (/,) of the switchgear and controlgear. The
supply curren! shall be practically sinusoidal.

rated frequency with a tolerance of

re port.
~ª
Switchgear and controlgear wit h the exception of d.c. auxiliary equipment shall be tested al
% . The test frequency shall be recorded in the test

NOTE 2 Tests performed at 50 Hz on switching devices of the open type having no ferrous components adjacent
to the current-carrying parts should be deemed to prove the performan ce of the switching device when rated 60 Hz,
provided that the tempe rature-rise values recorded during the tests at 50 Hz do not exceed 95 % of the maximum
permissible values.
When tests are performed at 60 Hz, they should be considered valid far the same current rating with 50 Hz rated
frequency.
60694 © IEC:1996+A1:2000+A2:2001 - 141 -

The test shall be made over a period of time sufficient for the temperature rise to reach a
stable value. This condition is deemed to be obtained when the increase of temperature rise
does not exceed 1 K in 1 h. This criteria w ill normally be met alter a test duration of five times
the thermal time constan! of the tested device.

The t ime for the w hole test may be shortened by preheating the circuit w ith a higher value of
curren!, except w here the measurement of thermal time constan! is required.

6.5.3 Measurement of the temperature and the temperature rise

Precautions shall be taken to reduce the variations and the errors due to the time lag betw een
the temperature of the sw itching device and the variations in the ambient air temperature.

For coils, the method of measuring the temperature rise by variation of resistance shall
normally be used. Other methods are permitted only if it is impracticable to use the resistance
method.

The temperature of the various parts other than coils for w hich limits are specified shall be
measured w ith thermometers or thermocouples, or other sensitive devices of any suitable
type, placed at the hottest accessible point. The temperatu re rise shall be recorded at regu lar
intervals throughout the test w hen the calculation of the thermal t ime constan! is needed.

The surface temperature of a componen! immersed in a liquid dielectric shall be measured

only by thermocouples attached to the surface of this componen!. The temperature of the
liquid dielectric itself shall be measured in the upper laye r of the dielectric.

For measurement w ith thermometers or thermocouples, the follow ing precautions shall be
taken:

a) the bulbs of the thermometers or thermocouples shall be protected aga inst cooling from
outside (dry clean w ool , etc. ). The protected area shall , how ever, be negligible compared
with the cooling area of the apparatus under test;
b) good heat conductivity betw een the thermometer or thermocouple and the surface of the
part under test shall be ensured ;
c ) when bulb thermometers are employed in places w here there is any varying magnetic
field, it is recommended to use alcohol thermometers in preference to mercury thermo-
meters, as the latter are more liable to be influenced under these conditions.

6.5.4 Ambient air temperature

The ambient air temperature is the average temperature of the air surrounding the sw itchgear
and controlgear (for enclosed sw itchgear and controlgear, it is th e air outside the enclosure).
lt shall be measured during the last quarter of the test period by means of at leas! t hree
thermometers , thermocouples or other temperature-detecting devices equally distributed
around the sw itchgear and controlgear at about the average height of its current-carrying
parts and at a distance of about 1 m from the sw itchgea r and controlgear. The thermometers
or thermocouples shall be protected against air currents and undue influence of heat.

In order to a void indication errors because of rapid temperature changes , the thermometers or
thermocouples may be pul into small bottles containing about 0 ,5 1 of oil.
60694 © IEC:1996+A1:2000+A2:2001 - 143 -

During the last quarter of the test period , the change of ambient air temperature shall not
exceed 1 K in 1 h. lf this is not possible because of unfavourable temperature conditions of
t he test room , the temperature of an ident ical sw itchgear and controlgear under the same
conditions , but without curren!, can be taken as a substitute for the ambient air temperature.
This additional switc hgear and controlgear shall not be subjected to an undue amount of heat.

The ambient air temperature during tests shall be more than +1 0 ºC but less than +40 ºC. No
correction of the temperature-rise values shall be made for ambient air temperatures w ithin
this range.

6.5.5 Temperature-rise test of the auxiliary and control equipment

The test is made with the specified supply (a.c. or d.c.), and for a.c. al its rated frequency
(tolerance ~~ %) .
NOTE Tests perfo rmed al 50 Hz on switching devices of the open type having no ferrous components adjacent to
the current-carrying parts should be deemed to prove the performance of the switching device when rated 60 Hz,
provided that the temperature-rise values recorded during the tests at 50 Hz do not exceed 95 % of the rnaximum
permissibte values _W hen tests are performed at 60 Hz they should be considered valid far the same current rating
with 50 Hz rated frequency

The auxiliary equipment shall be tested at its rated supply voltage (U8 ) or at its rated curren!.
The a.c. supply voltage shall be practical ly sinusoidal.

Continuously rated coils shall be tested over a period of time suffic ient for the temperature
rise to reach a constan! value. This condition is usually obta ined w hen the variation does not
exceed 1 K in 1 h.

For circu its energized only during switching operations , the tests shall be made under the
following conditions:

a) when the sw itching device has an automatic breaking device for interruption of the
auxiliary circuit at the end of the operation , the c ircuit shall be energized 10 t imes, for
either 1 s or until the automatic breaking device operates, the interval betw een the instan!
of each energizing being 10 s or, if the construction of the sw itching device does not
permit this, the lowest interval possible ,
b) when the sw itching device has no automatic breaking device for interruption of the
auxiliary circuit at the end of the operation, the test shall be made by energizing the circuit
once for a duration of 15 s.

6.5.6 lnterpretation of the temperature-rise tests

The temperature rise of the various parts of the switchgear and controlgear or auxil iary
equipment for which limits are specified, shall not exceed the values spec ified in table 3.
Otherwise, the switchgear and controlgear shall be considered to have failed the test.

When the arcing contacts are bare copper contacts and are separate from but in parallel w ith
the main contacts, the temperature rise of the main contacts and of the arcing contacts shall
not exceed the values given in table 3.

11 the insulat ion of a coil is made of several difieren! insulating materials , the permissible
temperature rise of the coil sha ll be taken as that for the ins ulating material with the lowest
limit of temperature rise.
60694 © IEC:1996+A1:2000+A2:2001 - 145 -

lf the sw itchgear and controlgear is fitted w ith v arious equipment complying w ith particular
standards (for example, rectifiers, motors, low-voltage switches, etc. ), t he temperature rise of
such equipment shall not exceed the limits specified in the relevan! standards.

6.6 Short-time withstand current and peak withstand current tests

Main circuits and , w here applicable , the earthing circu its of the switchgear and controlgear
shall be subjected to a test to prove t heir ability to carry the rated peak w ithstand curren! and
t he rated short-time w ithstand curren!.

The test shall be made at the rated frequency w ith a tolerance of ± 1O % at any suitable
v oltage and starting at any convenient ambient temperature.

NOTE For convenience of testing, wi der tolerances of the rated frequency may be necessary. lf the deviations a re
appreciable , i.e. when switchgear and controtgear rated for 50 Hz are tested at 60 Hz and vice versa, care should
be taken in the interpretation of results.

6.6.1 Arrangement of the switchgear and controlgear and of the test circuit

The sw itchgear and controlgear shall be mounted on its ow n support or on an equivalen!

support and installed w ith its own operating dev ice as far as necessary to make the test
representative. lt shall be in the closed position and f itted w ith clean contacts in new
condition.

Each test shall be preceded by a no-load operation of the mechanical sw itching devic e and ,
w ith the exception of earthing sw itches, by measurement of the resistance of the main circuit.

The test may be made three-phase or single-phase. In the case of a s ingle-phase test, the
following shall apply:

- on a three-pole sw itchgear and controlgear, the test shall be made on two adjacent poles;
- in the case of sw itchgear and controlgear w ith separated poles , the test may be made
either on tw o adjacent poles or on one pole w ith the return conductor at phase distance. lf
the distance between poles is not fixed by the design , the test shall be made at the
mínimum distance indicated by t he manufacturer;
- above a rated voltage of 72,5 kV, unless otherwise specified in the relevan! standards , the
return conductor need not be taken into account, but in no c ase shall it be located closer
to the tested pole than the mínimum distance indicated for phase centres by the
manufacturer.

The connections to the terminals of the switchgear and controlgear shall be arranged in such
a wa y as to avoid unrealistic stress ing of the terminals. The distance betw een t he terminals
and the nearest supports of the conductors on both sides of the sw itchgear and controlgear
shall be in accordance w ith the instructions of the manufacturer.

The test arrangement shall be noted in the test report.

6.6.2 Test current and duration

The a.c. componen! of the test curren! s hall, in principie , be equal t o the a.c. componen! of
the rated short-time w ithstand curren! (/k) of the switchgear and controlgear. The peak curren!
(f or a three-phase circuit, th e highest value in one of the outer phases) shall be not less than
the rated peak w ithstand curren! (/p) and shall not exceed it by more than 5 % w ithout the
consent of the manufacturer.
60694 © IEC:1996+A1:2000+A2:2001 - 147 -

Far three-phase tests, the curren! in any phase shall not vary from the av erage of the currents
in the three phases by more !han 1O % . The average of the r.m.s. val u es of the a.c.
componen! of the test currents shall be not less than the rated value.

The test curren! /1 shall in principie be applied far a time 11 equal to the rated duration lk of
short circuit.

lf no other method to determine the value t12 t1 is available, then it shall be determined from
the oscillogram using the method of evaluating /1 given in annex B. The value of 1¡2 t1 on test
shall be not less than the value of /k2tk calcu lated from the rated short-time curren! (/k) and
the rated duration of short c ircuit (tk), and shal l not exceed this value by more than 10 %
w ithout the cansen! of the manufacturer.

When, however, the characteristics of the test plan! are such that the peak and r.m.s. values
of test curren! specified above cannot be obtained in a test of the specified duration , the
fallowing deviations are permitted:

a) if the decrement of the short-circuit curren! of the test plan! is such that the specified
r.m.s. value , measured in accordance with annex B or by an equivalen! cannot be
obtained far the rated duration w ithout applying initially an excessively high curren!, the
r.m.s. value of the test curren! may be permitted to fall below the specified value during
the test and the duration of the test may be increased appropriately, provided that the
va lue of the peak curren! is not less !han that specified and the time is not more than 5 s;
b) if, in arder to obta in the required peak curren!, the r.m.s. value of the curren! is increased
above the specified value, the duration of the test may be reduced accordingly;
c) if neither a) nor b) is practicable, separation of the peak w ithstand curren! test and the
short-time w ithstand curren! test is perm issible. In this case two tests are made:
far the peak w ithstand curren! test, the time du ring w hich the short-circuit curren! is
applied shall be not less than 0,3 s;
far the short-time w ithstand curren! test, the time during w hich the short-circuit curren!
is applied shall be equal to the rated duration. However, deviation in time according to
item a) is permitted.

6.6.3 Behaviour of switchgear and controlgear during test

AII sw itchgear and controlgear shall be capable of carrying their rated peak w ithstand curren!
and their rated short-time w ithstand curren! w ithout causing mechanical damage to any part
or separation of the contacts.

lt is recognized that, during the test, the temperature rise of current-carrying and adj acent
parts of the mechanical sw itching device may exceed the limits specified in table 3. No
temperature-rise limits are specified far the short-time curren! w ithstand tests but the
maximum temperature reached should not be sufficient to cause significan! damage to
adjacent parts.

6.6.4 Conditions of switchgear and controlgear after test

After the test, the switchgear and controlgear shall not show significan! deterioration, shall be
capable of operating normally, carrying its rated normal curren! continuously without
exceeding the temperature-rise limits specified in table 3 and withstanding the voltage
specified under dielectric tests.
60694 © IEC:1996+A1:2000+A2:2001 - 149 -

lf the mechanical switching device has a rated making and/or breaking capacity, then the
condition of the contacts shall not be such as to affect the performance materially at any
making and/or breaking curren! up to its rated value.

The following is sufficient to check these requirements:

a) a no-load operation of the mechanical sw itching device shall be performed immediately

alter the test, and the contacts shall open at the first attempt;
b) secondly, the resistance of the main circuit shall be measured according to 6.4.1 (except
for earthing sw itches). lf the resistance has increased by more than 20 %, and if it is not
possible to confirm the condition of the contacts by visua l inspection, it may be
appropriate to perform an additional temperature-rise test.

6.7 Verification of the protection

6.7.1 Verification of the IP coding

In accordance w ith the requirements specified in clauses 11, 12, 13 and 15 of IEC 60529 ,
tests shall be performed on the enclosures of sw itchgear and controlgear fully assembled as
under service conditions. As real c able connections entering the enclosures are not normally
installed for type tests, corresponding filler pieces shall be used. Transport units of sw itchgear
shall be closed for the tests by covers providing identical protection qualities as for the joints.

The tests shall , how ever, be made only if there are doubts regarding the compliance w ith
these requirements, in each position of the relevan! parts as deemed necessary.

When the supplementary letter W is used, a recommended test method is given in annex C.

6.7.2 Mechanical impact test

When agreed betw een manufacturer and user, enclosures for indoor installation shall be
subjected to an impact test. Three b low s are applied to points of the enclosure that are likely
to be the weakest points of each enclosure. Devices such as relays , meters, etc. , are
excepted.

The hammer head w ith which the impact is applied has a hemispherical tace w ith a radius
of 25 mm of steel having a Rockwell hardness of R100. T he use of a spring-operated impact
test apparatus as defined in I EC 60068-2-63 is recommended.

Alter the test, the enclosure shall show no breaks and the deformation of the enclosure shall
not affect the normal function of the equipment, reduce the insulating and/or creepage
distances or reduce the specified degree of protection against access to hazardous parts
below the permitted values. Superficial damage, such as removal of paint, breaking of cool ing
ribs or of similar parts , or depression of small dimension can be ignored.

The tests shall , how ever, be made only if there are doubts regarding the compliance w ith
t hese requirements, in each position of the relevan! parts as deemed necessary .

For outdoor installat ion, the test shou ld be agreed betw een manufacturer and user.
60694 © IEC:1996+A1:2000+A2:2001 - 151 -

6.8 Tightness tests

The purpose of tightness tests is to demonstrate that the absolute leakage rate F does not
exceed the specified value of the permissible leakage rate Fp.

Where possible. the tests should be performed on a complete system at Pre (or Pre)- 11 this is
not practica!, the tests may be performed on parts , components or sub-assemblies. In such
cases, the leakage rate of the total system shall be determined by summation of the
componen! leakage rates using the tightness coordination chart TC (see annex E). The
possible leakages betw een sub-assemblies of different pressures shall also be taken into
account.

The tightness test of sw itchgear and controlgear containing a mechanical sw itching device
shall be performed both in the closed and open position of the device, unless the leakage rate
is independent of the position of the main contacts .

In general, only cumulative leakage measurements allow calculation of leakage rates.

The type test report should include such information as:

- a description of the object under test, including its interna! volume and t he nature of the
filling gas or liquid;
- w hether the object under test is in the c losed or open pos ition (if applicable);
- the pressures and temperatures recorded at the beginning and end of the test and the
number of replen ishments (if any needed);
- the cut-in and cut-off pressure settings of the pressure (or dens ity) control or monitoring
device;
- an indication of the calibration of the meters used to detect leakage rates ;
- the results of the measurements ;
- if applicable, the test gas and the conversion factor to assess the results.

The tightness tests shall be performed in connection w ith the tests required in the relevan!
standards, typically befare and alter the mechanical operation test or during the operation
tests at extreme temperatures.

An increased leakage rate at extreme temperatures (if such tests are required in the relevan!
standards) is acceptable, provided that this rate resets to a value not higher than the
maximum permissible value at normal ambient air temperature. The increased temporary
leakage rate shall not exceed the values g iven in table 12.

In general, for the application of an adequate test method, reference is made to IEC 60068-2- 17.

Table 12 - Permissible temporary leakage rates for gas systems

Temperature class Permissible temporary leakage rate

ºC
+40 and +50 3FP
am bie nt tempe rature Fp
- 5 / -1 0 / -1 5 / - 25 /-40 3Fp
- 50
6 Fp
60694 © IEC:1996+A1:2000+A2:2001 - 153 -

6.8.1 Controlled pressure systems far gas

The relative leakage rate F rel shall be checked by measuring the pressure drop t;.p over a time
period, 1 that is of sufficient length to permit a determination of the pressure drop (within the
filling and replenishing pressure range). A correction should be made to take into account the
variation of ambient air temperature. During this period the replen ishment device shall be
inoperativ e.

t;.p 24
F,el =- · 100 (% per day)
Pt

N= ~ . 24
Pr - Pm

w here t is the test duration (hours) .

NOTE In order to maintain the linearity of the formula , tip should be of the same arder of magnitude as Pr - Pm ·
Alternatively, the number of replenishment operations per day may be measured directly.

6.8.2 Closed pressure systems far gas

Due to comparatively small leakage rates of these systems, pressure drop measurements are
not applicable. Other methods (examples are given in annex E) may be used to measure the
leakage rate F , w hich al low s in combination with the tightness coordination chart TC, allows
one to calculate:

- the relative leakage rate F, 81 ;

- the time betw een replenishments T (outside extreme conditions of temperature or
frequency of operations).

In general the test Qm (see IEC 60068-2-17) represents an adequate method to determine
leakages in gas systems.

lf the test object is filled with a test gas different from the gas used in service and/ or at a test
pressure different from the normal operating pressure , corrective factors defined by the
manufacturer shall be used far calculations.

Since metering difficulties occur during low and high temperature tests, the procedure used
may be to perfarm the tightness test at ambient temperature befare and after the low and high
temperature tests to determine if there has been a change.

Since leakage rate measurements in practice may have an inaccuracy of ±50 %, the tightness
test is considered to be successful w hen the stated v alues of table 12 are achiev ed w ithin the
limits of +50 %. This inaccuracy of measurement shall be taken into account when calculating
the period of time between replenishments.

6.8.3 Sealed pressure systems

a) Sw itchgear using gas

Tightness tests on such switchgear and controlgear are performed in arder to determ ine
the expected operating life far the sealed pressure system.
The tests shall be performed accord ing to 6.8.2.
b) Vacuum sw itchgear
The vacuum lev el shall be measured tw ice w ithout operation of the vacuum tube , w ith a
time interval such that the rate of vacuum p ressure variation can be properly assessed .
60694 © IEC:1996+A1:2000+A2:2001 - 155 -

This rate shall be such that the vacuum pressure level w ill not reach t he maximum acceptable
threshold during its expected operating life. The mínimum time interval depends en the size of
t he vacuum tube and the sensitivity of the testing method.

NOTE Generally, a time interval of four weeks is considered acceptable.

The chosen method fer measuring the vacuum shal l be cal ibrated fer each type of vacuum
tube. This can be done by applying the test method simultaneously w ith a conv entional
vacuum pressure measurement before sealing a sample unit. The accuracy of the ev aluation
shall be established by repeat ing the measurements.

6.8.4 Liquid tightness tests

The purpose of tightness tests is to demonstrate that the total system leakage rate F I;q does
not exceed the specified value Fp(liq )·

The object under test shal l be as in service conditions with all its accessories and its normal
fluid , mounted as close as possible as in service (framew ork, fixing ).

The tightness tests shall be perfermed in connect ion w ith the tests required in the relevan!
standards, typically before and after the mechanical operation test, during the operation tests
at extreme temperatures or before and after the temperature-rise tests.

An increased leakage rate at extreme temperatures (if such tests are required in the relev an!
standards) and/ or during operations is a cceptable, provided that this rate resets to the initial
value after the temperature is returned to normal ambient air temperature and/or after the
operations are perfermed. The increased temporary leakage rate shall not impair the safe
operation of the sw itchgear and controlgear.

The sw itchgear shall be observed over a period sufficient to determine a possible leak or the
pressure drop t>p. In this case, the calculations given in 6.8.1 are val id.

NOTE Using liquids different from those in service or gas for the test is possible but req uires justification by the
manufacture r.

The test report should include such infermation as :

- a general description of the object under test;

- the number of operations perfermed ;
- the nature and pressure(s) of the liqu id ;
- the ambient air temperature during test;
- the results w ith the switchgear device in closed and in open position (where applicable) .

6.9 Electromagnetic compatibility tests (EMC)

EMC requirements and tests are specified only fer secondary systems.

Fer main circuit of switchgear and controlgear in normal operation, w ithout sw itching
operations , the emission level is verified by means of the radio interference voltage test,
see 6.3.

Emission caused by sw itching operations , including interruption of fault currents , is incidental.

60694 © IEC:1996+A1:2000+A2:2001 - 157 -

The frequency and level of such emission are considered to be part of the normal
electromagnetic environment.

For secondary systems of switchgear and controlgear, the EMC requirements and tests
specified in this standard have precedence over other EMC specifications.

6.9.1 Emission tests on secondary systems

Electronic equipment, w hich is part of the secondary system , shall fulfil the requ irements w ith
regard to emission , as defined in CISPR 11 for group 1, c lass A equipment. No other tests are
specified.

A 10 m measuring distance may be used instead of 30 m , by increasing the limit values by 10 dB.

6.9.2 lmmunity tests on secondary systems

6.9.2.1 General

Secondary systems of switchgear and controlgear shall be subjected to electromagnetic

immunity tests if they include electronic equipment or components. In other cases no tests are
required.

The follow ing immunity tests are specified:

- electric fast transient/burst test (see 6.9.2.2) . The test simulates the conditions caused by
sw itching in the secondary circu it;
- oscil latory wave immunity test (see 6.9.2.3). The test simulates the conditions caused by
switching in the main c ircuit.

Other EMC immunity tests do exist, but are not specified in this case. A compilation of EMC
immunity tests is given in IEC 61000-4-1 , and IEC 6 1000-6-5 deals with EMC immunity of
apparatus in pow er generating stations and high-voltage substations.

Electrostatic discharge (ESD) tests are normally required on electronic equipment, and shall
be performed on such equipment to be used in secondary systems of sw itchgear and
controlgear. These tests need not be repeated on complete secondary systems. Radiated
field and magnetic field tests are considered to be relevan! only in special cases.

NOT E 1 Example of a special case : electronic devices, placed in the close vicinity of the busbars of metal-
enclos ed switchgear , may be influenced by magnetic fie lds. Suppleme ntary arrangements may then be made in
order to e nsure e lectromagnetic compatibility.
NOT E 2 Use of radio-transmitters or cellular telephones clos e to a control cabinet with ope n door may subject the
secondary system to considerable radio-freque ncy electromagnetic fields.

6.9.2.2 Guidelines for immunity tests

Electromagnetic immun ity tests shall be made on complete secondary systems or sub-
assemblies. Examples are given in figures 5, 6, 7, and 8. The tests may be made on

- the complete secondary system;

- subassemblies , such as central control cubicle , operating mechanism cubicle, etc. ;
- subassembl ies w ithin a cubicle, such as metering or monitoring system.
60694 © IEC:1996+A1:2000+A2:2001 - 159 -

Ind ividual testing of subassemblies is strongly recommended in cases w here long lengths of
interconnections are needed, or w here significan! interference voltages are expected b etw een
t he subassemblies. Individual testing is mandatory for eac h interchangeable subassembly.

Subassemblies may be positioned in difieren! places w ithin the seco ndary system , w ithout
invalidating the t ype test of the complete system , provided that the overall w iring length and
t he number of individual w ires connecti ng t he subassembly t o the secondary syst em is not
greater than in the tested s ystem.

lnterc hangeable subassem blies may be replaced by sim ilar subassemblies, w ithout
invalidating the original type test, provided that

- rules far design and installation given in IEC 6 1000-5 are follow ed;
- type tests hav e been performed on the most c omplete subassembly applicable to the type
of switc hgear and controlgear;
- manufacturer's design rules are the same as f ar the type-tested subassembly.

The test voltage sha ll be applied to the interface of the secondary system or t ested
subassembly. T he interface shall be defined by the man ufacturer.

The type t est report shall clearly state what system or subassembly has been test ed. See also
annex A.
NO TE The immunity tests are inte nded to cove r a majority of service conditions. The re may be extreme situations
where induced disturbances a re more seve re than those covered by the tests

6.9.2.3 Electrical fast transient/burst test

An electrical fast transient/burst test shall be performed in accordance w it h IEC 6 1000-4-4.

The test voltage and c oupling shall be chosen according to table 17.

Table 17 - Application of voltage at the fast transient/burst test

Interface Normal EMC Reduced EMC Coupling

severity class severity class

Test voltage Test voltage

kV kV

Powe r lines 2 2 CDNª

Contro l lines 2 2 CDN
Com munication a nd shielded lines 2 2 Capacitive
coupling clamp

Earth terminal 2 2 CDN

ª CON: coupling decoupling network.
60694 © IEC:1996+A 1:2000+A2:2001 - 161 -

6.9.2.4 Oscillatory wave immunity test

An osc ill atory w a ve immunity test shal l be performed , wit h shape and duration of t he test
volt age in accordance w ith IEC 6 1000-4-12.

Damped oscillatory w ave tests shall be made at 100 kHz and 1 MHz, wit h a relative tolerance
of ±30 %.

Disconnector operations in GIS may create surges with extremely steep w ave fronts. For that
reason, additional test frequencies are under consideration for equipment nearby GIS (1 O MHz
and 50 MHz).

Tests shall be made for both common a nd differential mode. The test voltage and coupling
method s ha ll be chosen according to table 18.
NOTE The increased test voltage values for instrument tra nsformer secondari es reflect actual disturbance values
recorded in field installations.

Table 18 - Application of voltage at the damped oscillatory w ave test

Inte rface Normal EMC severity class Reduced EMC seve rity class Coupling
Test voltage Test voltage
kV kV
Power lines Differential mode: 1,0 (2,5ª) Differential mode: 0 ,5 CDNb
Common mode: 2 ,5 Common mode: 1,0 CDN
Control lines Differential mode: 1,0 (2,5ª) Differen tial mode : 0 ,5 CDN
(measurement)
Common mode: 2 ,5 Common mode: 1,0 CDN
Communication Differential mode: 1,0 Differential mode: 0 ,5 CDN
(unshielded)
Common mode 2.5 Common mode· 1.0 CDN
Shielded lines 2,5 1,0 Between cabinets
a Far secondary circuits of instrument transformers only.
b CON: coupling decoupling network.

6 .9.2.5 Behaviour of the secondary e quipme nt during and after test s

The secondary system shall w ithstand each of t he tests specified in 6.9 .2.2 and 6.9.2.3
w it hout permanent damage. After the tests it shall still be full y operative. Temporary loss of
parts of th e functio nality is perm itted accord ing to table 19.
60694 © IEC:1996+A1:2000+A2:2001 - 163 -

Table 19 - Assessment criteria for transient disturbance

immunity tests

Function Criterionª

Protection, teleprotection 1
A larm 2
Supervision 2
Command and control 1

Measurement 2
Counting 1
Data processing
- for high-speed protective system 1
- for general use 2
lnformation 2
Data storage 1
Processing 2
Monito ring 2
Man- machine interface 2
Self-diagnostics 2
Process ing, monitoring and self-diagnostic functions which are on-line connected, and are part of
command and control circuits , shall fulfil criterion 1.

ª Criteria , according to I EC 61000-4-1

1· normal performance within the specification limits;
2: temporary degra dation ar loss of function or performance which is self- recoverable.

6.1 O Additional tests on auxiliary and control circuits

6.10.1 General

The objective of the t ests described below is to qualify the whole assembly without repeating
individual tests on compon ents. Therefore, tests on components which comply w ith their
relevan! IEC standards and wit h re levan! rated values shall not be repeated.

6.10.2 Functional tests

A f unctional test of all low-voltage circuits shall be made to verify the proper functioning of
auxiliary and cont rol circuits in conj unction wit h the other parts of the sw itchgear and
controlgear. T he test procedures depend on the nature and the complexity of the low-volt age
circuits of the device. These tests are spec ified in the relevan! IEC standards for sw itchgear
and controlgear. They shall be performed w ith the upper and low er value limits of the supply
voltage defined in 4.8.3.

For low -voltage circuits , sub-assemblies and components , operation tests can be omitted if
t hey have been fully performed during a test appl ied to t he w hole sw itchgear and controlgear
or in relevan! circumstances.
60694 © IEC:1996+A1:2000+A2:2001 - 165 -

6.10.3 Electrical continuity of earthed metallic parts test

A test shall be performed on auxiliary and control circuit enclosures.

The test equipment comprises a d.c. power supply with a maximum open circuit voltage of 12 V d.c.,
an output curren! regulator, and voltage and curren! measuring instruments.

A mínimum curren! of 2 A shall be circulated betw een the main earthing connections and each
of the follow ing mechanical masses , if applicable:

- doors ;
- door handles;
- trames;
- metallic enclosures.

NOTE lt may be necessary to locally remove coating at measuring points.

The auxiliary and control circuits enclosures of sw itchgear and controlgear shal l be
considered to have passed the test if the measured resis tance is below 0,5 O.

6.10.4 Verification of the operational characteristics of auxiliary contacts

6.10.4.1 General

Auxiliary conta cts , w hich are contacts included in auxiliary circuits, shall be submitted to the
following tests unless the equipment has passed the w hole type tests as a functional unit.

6.10.4.2 Auxiliary contact rated continuous curren!

This test verifies the rated v alue of curren! w hich a previously closed auxiliary contact is
capable of carrying continuously.

The circuit shall be closed and opened by means indepe ndent from the contact under test.
Test procedures are described in 6.5.5. The contact shall carry its class rated continuous
curren! accord ing to table 16 without exceeding the temperature rise in table 3 based on the
contact material and the working environment.

6.10.4.3 Auxiliary contact rated short time withstand curren!

This test v erifies the v alue of curren! w hich a previously closed auxiliary contact is capable of
carrying for a spec ified short period.

The circuit shall be closed and opened by means independent from the contact under test.
The contact shall carry its class rated short time withstand curren! according to table 16 for 30 ms,
with a resistive load. This implies that the curren! value to be obtained shall be reached w ithin 5 ms
after curren! initiation. The relative tolerance on the test curren! amplitude is +S o/o and the relative
-0
10
tolerance on the test curren! duration is + % .
-0

This test shall be repeated 20 times with a 1 min interval betw een each test. The contact
res istance value shall be taken before and after the tests , w ith the contacts al ambient
temperature for both measurements. The resistance increase shall be less than 20 %.
60694 © IEC:1996+A1:2000+A2:2001 - 167 -

6.10.4.4 Auxiliary contact breaking capacity

This test verifies the breaking capacity ol an auxiliary contact.

The circuit shall be closed by means independent lrom the contact under test. The contact
shall carry lor 5 s and shall break the curren! associated w ith its class according to t able 16,
10
with an inductive load. The relative tolerance on the test voltage is + % and the relative
-0
5
to lerance on the test curren! amplitude is + % .
-0

For all classes , the circuit time constan! shall not be less than 20 ms w ith a relative tolerance
ol +20%_
-0

This test shall be repeated 20 times w ith a 1 min interval betw een each test. The recovery
voltage shall be mainta ined during each 1 min interval and for 300 ms ± 30 ms alter the las!
operation. The contact res istance value shall be taken before and alter the tests, w ith the
contacts at ambient temperature lor both measurements. The resistance increase shall be
less than 20 % .

6.10.5 Ripple on d.c. input power port immunity test

This test is performed according to IEC 61000-4-17 and applies to electrical and electronic
components. T he relevan! IEC standards for sw itchgear and controlgear should state w hether
or not such a test is necessary on sorne components (for example , it does not apply to
motors, motor-operated disconnectors , etc.).

The test level is class 2, and the lrequency ol the ripple is equal to three t imes the rated
lrequency.

The assessment criterion is: "normal performance w ithin the specilication limits" (criterion a).

6.10.6 Voltage dips, short interruptions and voltage variations

on d.c. input power port immunity tests

Relerence to IEC 61000-4-29 is under consideration.

6.10.7 Environmental tests

6.10.7.1 General

Tests on all parts ol auxiliary and control equipment should be made under conditions l ully
representative ol !hose that pertain w hen mounted , housed or operated as in the complete
sw itchgear and controlgear. Such cond itions are satislied w hen the tests are made on
complete sw itchgear and controlgear as stated in 6.1.1. Where this is not done , care shall be
taken to ensure that tests are carried out under conditions relevan! to operation in the
complete sw itchgear and controlgear.

Environmental tests shal l be made in order to assess:

- the efficiency ol t he precautions taken ;

- the proper lunctioning ol auxiliary and control circuits over the whole range ol actual
service conditions inside the enclosures.
60694 © IEC:1996+A1:2000+A2:2001 - 169 -

AII these tests shal l be carried out on the same equipment assembly.

These tests may be carried out on the cubicle by itself, or associated with the switchgear and
controlgear.

Each environmental test of the auxiliary and control circuits can be omitted , if covered by a
test applied to the w hole switchgear and controlgear.

Once an equipment has successfully passed the environmental tests, it may be attached to
the switchgear and controlgear in several ways (directly mounled on the trame, located
separately as a local control cubicle, etc. ).

Environmental tests should preferably be made on complete auxiliary and control circuits.
Such tests , made on a representative auxi liary and control circuits assembly, are considered
to verify the proper functioning of sim ilar auxiliary and control circuits assemblies belonging to
the same range of switchgear and controlgear equipment.

Environmental tests do not need to be repeated if the rated voltage of the auxiliary and
control circuits is changed.

The change of rated supply voltage of auxiliary and control circuits may have , for sorne
designs, an impact on the results of environmenta l tests. In practice , un less otherwise
justified by the manufacturer, it is desirable to perform the environmenlal tests on auxiliary
and control circuits having the highest rated supply voltage in order to cover all other simi lar
auxiliary and control circuits designed for lowe r rated supply voltages.

As environmental tests verify the proper functioning of auxiliary and control circuits over the
w hole range of service conditions in normal operation , heating elements shall be ready to
operate except w here otherwise stated . Actual service conditions w ill determine w hether the
heating elements are in circuit or not.

Al the end of the test duration, except for the vibration response test, auxiliary and control
circuits shall be checked to ascertain w hether they are capable of functioning in accordance
with the relevan! specifications. These checks will be based on a relevan! set of functions.
Auxiliary and control circuits shall be energ ised, and shall remain in the operating condilion
during and after the test until the functional checks have been performed.

The manufacturer shall clearly state w hich f unctionalities are checked at the end of the tests.

6.1 O. 7 .2 Cold test

A cold test shall be performed according to test Ad of IEC 60068-2-1 , under the service
conditions specified in clause 2. The test duration shall be 16 h.

6.1 O. 7 .3 Dry heat test

A dry heat test shall be performed according to test Ba of IEC 60068-2-2 , under the service
conditions specified in clause 2. The test temperature s hall be the maximum ambient air
temperature and the test duration shall be 16 h.

6.10.7.4 Damp heat, steady state test

A steady state humidity test shall be performed acco rding to test Ca of IEC 60068-2-3. The
test duration sha ll be four days.
60694 © IEC:1996+A1:2000+A2:2001 -171 -

6.10.7.5 Cyclic humidity test

A cyclic humidity test shall be performed according to test Db of IEC 60068-2-30. The upper
temperature shall be the maximum ambient air temperature specified in cla use 2 and the
number of temperature cycles shall be two. Variant 2 may be used fer the temperature fall
period and recovery shall take place under standard atmospheric conditions. No special
precautions shall be taken regarding the removal of surface moisture.

6.10.7.6 Vibration response and seismic tests

As the vibration response test is not covered by IEC 60068-2-6 , reference is made to
IEC 60255-21 - 1.

This test aims to determine any mechanical w eakness of the auxiliary and control equipment
assembly. Damage may be caused by tw o different vibration sources:

- vibrations due to operation of the associated sw itchgear or controlgear w hich are highly
dependen! en site installation. The test shall be performed according to IEC 60255-21 - 1.
Vibration response test parameters are !hose correspond ing to severity class 1. This test
can be omitted if the auxiliary and control equipment assembly w as subjected to the
relevan! mechanica l endurance tests in the complete switchgear and controlgear;
- vibrations due to special service conditions specified in 2.2.4. The test w ill be performed
by agreement between manufacturer and user. In this case, an appropriate seismic test
according to IEC 60255-2 1-3, test severity class 1, should be considered.

The secondary system shall w ithstand the vibration response test w ithout permanent damage.
Alter the test, it shall still be fully operational. Temporary loss of parts of the functionality is
permitted during the test according to criteria stated in table 19.

6.10.7.7 Other environmental tests

By agreement between manufacturer and user (see 2.2.5), other environmental tests may be
performed according to IEC 60068-2.

6.10.7.8 Final condition check

The pow er frequency voltage w ithstand tests according to 6.2.10 shall be repeated alter all
other t ype tests have been completed, to confirm that there has been no reduction of
performance during testing.

7 Routine tests

The routine tests are fer the purpose of revealing faults in material or construction. They do
not impair the properties and reliability of a test object. The routine tests shall be made
wherever reasonably practicable at the manufacturer's w orks en each apparatus manu-
factured, to ensure that the product is in accordance with the equipment en w hich the type
tests have been passed. By agreement, any routine test may be made en site.

The routine tests given in t his standard comprise:

a) dielectric test on the main circuit in accordance w ith 7. 1;

b) tests en auxiliary and control circuits in accordance w ith 7.2;
c) measurement of the resistance of the main circu it in accordance w ith 7.3;
60694 © IEC:1996+A1:2000+A2:2001 - 173 -

d) tightness test in accordance with 7.4;

e) design and visual checks in accordance w ith 7.5.

Additional routine tests may be necessary and w ill be specified in !he relevan! IEC standards.

When sw itchgear and controlgear are no! completely assembled before transport, separate
tests shall be made on all transport units. In this event, !he manufacturer shall demonstrate
! he validity of his test (example: leakage rate, test voltage , resistance of par! of !he main
circuit).

Test reports of !he routine tests are normally no! necessary un less otherwise agreed upon
between manufacturer and user.

7.1 Dielectric test on the main circuit

A dry, short-duration pow er-frequency voltage test shall be applied. The test shal l be made
according to IEC 60060-1 , and to 6.2 on complete apparatus or on separate poles, or on
transport units in new, clean and dry conditions.

The test voltage shall be that specified in column 2 of tables 1 or 2, according to !he relevan!
IEC standards, or !he applicable par! of it.

When !he insulation of sw itchgear and controlgear is provided only by solid-core ins ulators
and air al ambient pressure, !he pow er-frequency voltage withstand test may be omitted if !he
dimensions betw een !he conductive parts - betw een phases , across open sw itching dev ice
and betw een conductive parts and !he trame - are checked by dimensional measurements.

Bases for !he checking of dimens ions are !he dimensional (outline) draw ings , w hich are par!
of !he type test report (or are referred to in it) of !he particular switchgear and controlgear.
Therefore , in these drawings all informat ion necessary for dimensional checking including !he
permissible tolerances shall be given.

7.2 Tests on auxiliary and control circuits

7.2.1 lnspection of auxiliary and control circuits, and verification of conformity

to the circuit diagrams and wiring diagrams

The nature of !he materials, !he quality of assembly, !he finish and, if necessary, !he
protective coatings against corrosion shall be checked. A visual inspection is also necessary
to check !he satisfactory installation of !he thermal insulation.

A visual inspection of actuators, interlocks, locks , etc. , shall be made.

Components for auxiliary and control circuits inside enclosures shall be checked for proper
mounting. The locat ion of !he means provided for connecting externa! w iring shall be checked
to ensure that there is sufficient wiring space for spreading of !he cores of multi-core cables
and for !he proper connection of !he conductors.

The conductors and cables shal l be checked for proper routing. Special attention shall be
given to ensure that no mechanical damage can occur to conductors and cables due to !he
proximity of sharp edges or heating elements , orto !he movement of moving parts.
60694 © IEC:1996+A1:2000+A2:2001 - 175 -

Furthermore, !he identification of components and terminals and, if applicable , ! he

identification of cables and w iring shall be verified. In addition , !he conformity of auxiliary and
control circuits to the circu it diagrams and w iring diagrams shall be checked and the technica l
data prov ided by the manufacturer (for example, number of free auxiliary contacts and ! he
class of each one , number, type and capacity of contacts other ! han auxiliary and control
contacts , electrical pow er of s hunt releases , etc .).

7.2.2 Functional tests

A functional test of all low-voltage circuits shall be made to verify the proper functioning of
auxiliary and cont rol circuits in conjunction w it h the other parts of the sw itchgear and
controlgear. The test procedures depend on the nature and the complexity of the low-voltage
circuits of !he device. These tests are specified in the relevan! IEC standards for sw itchgear
and controlgear . They shall be performed w ith !he upper and low er limits values of the supply
voltage defined in 4.8.3.

Operation tests on low-voltage c ircuits, sub-assemblies and components can be omitted if

t hey have been ful ly t ested during a test applied to !he whole sw itchgear and controlgear.

7.2.3 Verification of protection against electrical shock

Protect ion against direct contact with !he main circuit and sale accessibility to the auxiliary
and control equipment parts liable to be touched during normal operation shall be checked.
W here possible (for example, w ithout removing any coating), the electrical cont inuity of
earthed metallic parts shall be tested under the same conditions as those detai led in 6.1 0 .3.
W here not possible, a visual inspection shall be performed .

7 .2.4 Dielectric tests

Only pow er frequency tests shall be performed . This test shall be made under the same
conditions as ! hose detailed in 6.2.10.

The test voltage shall be 1 kV w ith a duration of 1 s.

7.3 Measurement of the resistance of the main circuit

For the rout ine test, the d.c. voltage drop or resistance of each pole of the main circuit shall
be measured under conditions as nearly as possible s imilar w ith regard to ambient air
temperature and points of measurement to !hose under w hich !he corresponding type test w as
made. The test curren! should be w ithin the range stated in 6.4.1.

The measured resistance shall no! exceed 1,2 Ru, w here Ru is equal to !he resistance
measured before the temperature- rise test.

7.4 Tightness test

Routine tests shall be performed at normal ambient air temperature wit h t he assembly filled al
! he pressure (or density) corresponding to !he manufacturer's test practice. For gas-f illed
systems sniffing may be used.

7 .4.1 Controlled pressure systems for gas

The test procedure corresponds to 6.8. 1.

60694 © IEC:1996+A1:2000+A2:2001 - 177 -

7.4.2 Closed pressure systems for gas

The test procedure corresponds to 6.8.2.

The test may be performed at different stages ol the manufacturing process or of assembl ing
on site, on parts, components and sub-assemblies , accord ing to the tightness coordination
chart TC.

7.4.3 Sealed pressure systems

a) Sw itchgear using gas

The test procedure corresponds to 6.8.3, item a).
b) Vacuum sw itchgear
Each vacuum tube shall be identified by its serial number. lts vacuum pressure level shall
be tested by the manufacturer in accordance w ith 6.8.3, item b).
The test results shall be documented and, if asked for, certified.

Alter assembly of the sw itchgear device the vacuum pressure level ol the vacuum tubes shall
be tested by a signilicant routine dielectric test across the open contacts. The test voltage
shall be stated by the manufacturer.

The dielectric test shall be carried out alter the mechanical routine test.

7.4.4 Liquid tightness tests

Routine tests shall be performed at normal ambient air temperature w ith the completely
assembled sw itchgear and controlgear device. Testing of sub-assemblies is also permissible.
In this case, a final check shall be performed at site.

The test methods correspond to those of the t ype tests (see 6.8.4).

7.5 Design and visual checks

The switchgear and controlgear shall be checked to verify its compliance w ith the purchase
specification.

8 Guide to the selection of switchgear and controlgear

To be spec if ied in the relevan! IEC standards for sw itchgear and controlgear.

9 lnformation to be given with enquiries , tenders and orders

To be spec if ied in the relevant IEC standards for switchgear and controlgear.

1 O Rules for transport, storage, installation, operation and maintenance

lt is essential that the transport, storage and installation of sw itchgear and controlgear, as
w ell as their operation and maintenance in service, be perlormed in accordance w ith
instructions given by the manufacturer.

Consequently, the manufacturer should provide instructions for the transport, storage ,
installation, operation and maintenance of switchgear and controlgear. The instructions for the
transport and storage should be given at a convenient time before del ivery, and the
instructions for the insta llation , operation and maintenance shou ld be given by the time ol
delivery at the lates!.
60694 © IEC:1996+A1:2000+A2:2001 - 179 -

lt is impossible, here, to cover in detail the complete rules for the installation, operation and
maintenance of each one of the different types of apparatus manufactured , but the following
information is given relative to the most importan! points to be considered for the instructions
provided by the manufacturer.

10.1 Conditions during transport, storage and installation

A special agreement should be made betw een manufacturer and user if the service conditions
of temperature and humidity defined in the order, cannot be guaranteed during transport,
storage and insta llation. Special precautions may be essentia l for the protection of insulation
during transport, storage and installation , and prior to energizing , to preven! moisture
absorption due , for instance, to ra in, snow or condensation. Vibrations during transport shall
be considered. Appropriate instructions should be given.

10.2 lnstallation

For each type of sw itchgear and controlgear the instructions provided by the manufacturer
should at least include the items listed below .

10.2.1 Unpacking and lifting

Required information for unpacking and lifting safely, including details of any special lifting
and positioning devices w hich are necessary, should be given.

10.2.2 Assembly

When the sw itchgear and controlgear is not fully assembled for transport, all transport units
should be clearly marked . Draw ings show ing assembly of these parts shou ld be provided w ith
the sw itchgear and controlgear.

10.2.3 Mounting

lnstructions for mounting of sw itchgear and controlgear, operating device and auxiliary
equipment should include sufficient deta ils of locations and foundations to enable site
preparation to be completed.

These instructions shou ld also ind icate:

- the total mass of the apparatus inclusive of extinguishing or insulating f luids;

- the mass of extinguishing or insulating fluids;
- the mass of the heaviest part of the apparatus to be lifted separately if it exceeds 100 kg.

10.2.4 Connections

lnstructions should inc lude information on:

a) connection of conductors , compris ing the necessary advice to preven! overheating and
unnecessary stra in on the switchgear and controlgear and to provide adequate clearance
distances;
b) connection of auxiliary circuits;
c) connection of liquid or gas systems, if any, including size and arrangement of piping;
d) connection for earth ing.
60694 © IEC:1996+A1:2000+A2:2001 - 181 -

10.2.5 Final installation inspection

lnstructions should be provided for inspection and tests w hich should be made after the
sw itchgear and controlgear has been installed and all connections have been completed.

These instructions shou ld include:

- a schedule of recommended s ite tests to establish corree! operation;

- procedures for carrying out any adjustment that may be necessary to obtain corree!
operation ;
- recommendations for any relevan! measurements that should be made and recorded to
help w ith future maintenance decisions;
instructions for final inspection and putting into service.

Guidance for electromagnetic compatibility site measurements is given in annex H.

10.3 Operation

The instructions given by the manufacturer should contain the follow ing information:

- a general description of t he equipment w ith particular attention to the technical description

of its characteristics and operation so that the user has an adequate understanding of the
main principies involved;
- a description of the safety features of the equipment and the operation of the interlocks
and padlocking facilities;
- as relevan!, a description of the action to be taken to man ipulate the equipment for
operation isolation, earth ing , maintenance and testing.

10.4 Maintenance

The effectiveness of maintenance depends mainly on the w ay instructions a re prepared by the

manufacturer and implemented by the user.

10.4.1 Recommendations for the manufacturer

a) The manufacturer should issue a maintenance manual including the follow ing information:
1) Extent and frequency of maintenance. For th is pu rpose the following factors should be
considered;
- sw itching operations (curren! and number);
- total number of operations ;
- time in service (period ic intervals );
- environmental conditions;
- measurements and diagnostic tests , (if any) .
2 ) Detailed description of the maintenance w ork;
- recommended place for the maintenance work (indoor, outdoor, in factory, on site, etc.);
- procedures for inspect ion, diagnostic tests , examination , overhaul ;
- reference to draw ings;
- reference to par! numbers ;
use of special equipment or tools;
precautions to be observed (e.g. cleanliness and possible effects of harmful arcing
by-products);
- lubrication procedures.
60694 © IEC:1996+A1:2000+A2:2001 - 183 -

3) Comprehens ive draw ings of the details of the sw itchgear and controlgear importan! for
maintenance, with clear identification (part number and description) of assemblies,
sub-assemblies and significan! parts.
NOTE Expanded deta il dra wings which indicate the relative position of components in assemblies and
sub-assemblies are a recommended illustration method.

4) Limits of values and tolerances which, w hen exceeded, make corrective action necessary.
For example:
- pressures , density levels;
resistors and capacitors (of the main circuit);
- operating times;
- resistance of the main circu its;
- insulating liquid or gas characteristics;
- quantities and quality of liquid or gas (see IEC 60480 and IEC 61634 for SF6);
- permissible erosion of parts subject to w ear;
- torques ;
- importan! dimensions.
5) Specifications for auxiliary maintenance materials, including warning of know n non-
compatibility of materials:
- grease;
oil ;
- fluid;
- clean ing and degreasing agents.
6) List of special tools, lifting and access equipment.
7) Tests alter the maintenance w ork.
8) List of the recommended spare-parts (description, reference number, quantities) and
advice for storage.
9) Estímate of active scheduled maintenance time .
1O) How to proceed w ith the equipment at the end of its operating lite , taking into
consideration environmenta l requirements.
b) The manufacturer should inform the users of a particular type of sw itchgear and control-
gear and about corrective actions required by possible systematic defects and failures.
c) Availability of spares:
The manufacturer should be responsible for ensuring the continued availabi lity of spare
parts required for maintenance for a period of not less than 1O years from the date of final
manufacture of the sw itchgear and controlgear.

10.4.2 Recommendations for the u ser

a) lf the user wishes to do his ow n maintenance, he should ensure that his staff have
sufficient qualification as w ell as a detai led know ledge of the respective sw itchgear and
controlgear.
b) The user should record the fol low ing information:
the serial number and the t ype of the sw itchgear and controlgear;
the date w hen the sw itchgear and controlgear is pul in service;
the results of all measurements and tests including diagnostic tests carried out during
the lite of the switchgear and controlgear;
dates and extent of the maintenance w ork carried out;
the history of service, periodical records of the operation counters and other
indications (e.g. short-circuit operations);
references to any failure report.
60694 © IEC:1996+A1:2000+A2:2001 - 185 -

c) In case of failure and defects, the user should make a failure report and should inform the
manufacturer by stating the special circumstances and measures taken. Depending upan
the nature of the failure, an ana lysis of the failure should be made in collaboration w ith the
manufacturer.

10.4.3 Failure report

The purpose of the failure report is to standardize the recording of the sw itchgear and
controlgear failures with the follow ing objectiv es:
- to describe the failure using a common terminology;
- to provide data for the user statistics;
- to provide a meaningful feedback to the manufacturer.

The follow ing gives guidance on how to make a failure report.

A failure report should include:

a) ldentification of the sw itchgear w hich failed:

substation name ;
identification of the sw itchgear (manufacturer, type, serial number, ratings);
sw itchgear family (air bias! , mínimum o il , SF6 , v acuum);
location (indoor, outdoor);
enclosure ;
operating mechanism, if applicable (hydraulic, pneumatic , spring , motor, manual) .
b) H istory of the switchgear:
date of commissioning of the equipment;
date of failure/ defect;
total number of operating cycles, if applicable;
date of las! maintenance ;
details of any changes made to the equipment since manufacture;
total number of operating c ycles since last maintenance;
cond ition of the sw itchgear when the failure/ defect w as d iscovered (in service ,
maintenance, etc.).
c ) ldentification of the sub-assembly/component responsible for the primary failure/defect
high-voltage stressed compone nts;
electrical control and auxiliary circuits;
operating mechanism, if applicable;
other components.
d) Stresses presumed contributing to the failure/ defect
Env ironmenta l conditions (temperature, w ind , ra in , snow, ice, pollution, lightning , etc. ).
e ) Classification of the failure/defect
majar failure;
m inar failure;
defect.
f) Origin a nd cause of the failure/defect
origin (mechan ical, electrical , tightness if applicable );
c ause (desig n, manufacture , inadequate instructions, incorrect mounting , incorrect
maintenance, stresses beyond !hose spec ified , etc. ).
60694 © IEC:1996+A1:2000+A2:2001 - 187 -

g) Consequences of the failure or defect

- sw itchgear dow n-time;
- time consumption for repair;
- labour cost;
- spare parts cost.
A failure report may include the follow ing information:
- draw ings, sketches;
- photographs of detective components;
- single-line station diagram;
- operation and timing sequences ;
- records or plots ;
- references to maintenance or operating manuals.

11 Safety

High-voltage sw itchgear and controlgear can be safe only when installed in accordance w ith
t he relevan! installation rules , and used and maintained in accordance with the manufacturer's
instructions (see clause 1O).

High-voltage sw itchgear and controlgear is normally only accessible by instructed persons. 11

shall be operated and maintained by skilled persons. When unrestricted access is available to
distribution sw itching and controlgear, additional safety features may be required.

The following specifications of this standard provide personal safety measures for sw itchgear
and controlgear against various hazards:

11.1 Electrical aspects

- insulation of the isolating distance (see 4.2);
- earthing (indirect contact) (see 5.3);
- separation of HV and LV circuits (see 5.4);
- IP coding (direct contact) (see 5.13.1 ).

11.2 Mechanical aspects

- pressurized components (see 5.2);
- manual actuating force (see 5.6.3);
- IP coding (moving parts ) (see 5.13.1 );
- mechanical impact protection (see 5.13.3).

11.3 Thermal aspects

- maximum temperature of accessible parts (see table 3);
- flammability (see 5.17).

11.4 Operation aspects

- dependen! pow er operation (see 5.5);
- manual charging (see 5.6.3);
- independent manual operat ion (see 5.7);
- interlocking devices (see 5.11 );
- position indication (see 5.12 ).
60694 © IEC:1996+A1:2000+A2:2001 - 189 -

Ka
1,50

m= 1

1,40
m = 0,9

m = 0,75
1,30

1,20

1, 10

1 000 1 500 2 000 2 500 3 000 3 500 4 000 H

IEC 316"'W5

These factors can be calculated from 4.2.2 o f IEC 60071-2 with the following equa tion:
Ka = 0 m (H-1 000)18150

where
H is the altitude in metres;
m is taken as fixed value in e ach c ase for simplification as follows
m = 1 fa r power-frequency, lightning impulse and phase-to -phase switching impulse vo ltages
m = 0,9 fa r longitud inal switching impulse voltage
m = O, 75 for phase-to- earth switching impulse voltage

Figure 1 - Altitude correction factor (see 2.2.1)

60694 © IEC:1996+A1:2000+A2:200 1 - 191 -

A B e A B e

b a b
l.
1 1
Frame F F

Closed Position Open

/IX .IJ7M

Figure 2 - Diagram of connections of a three-pole switching device (see 6.2.5.1 )

60694 10 IEC: 1996+A1 :2000+A2:2001 - 193 -

::::::I>======

J M

Zs

Delails of M
IEC JJ~

F Filler
Rt The equIvalent resIslance of R 1 in series with the parallel combmation of R 2 and the equIvalent resistance of
the measunng set
Zs May be e1lher a cepac1tor ora circuit composed of a capac1tor and en inductor m senes
L The 1mpedance usad to shunt power-frequency currents and to compensete for stray capacitance at the
measunng frequency

Figure 3 - Dlagram of a test circuit for the radio lnterference voltage test
of switching devlces (seo 6.3)
60694 © IEC:1996+A1:2000+A2:2001 - 195 -

Annex A
(normative)

ldentification of test specimens

The follow ing data and drawings , as applicable , shall be submitted by the manufacturer to the
testing laboratory, in respect of each test sample (but not necessarily included in the test
report). lnformation to be included in the test report is given in 6.1.3.

A.1 Data
- Manufacturer's name;
- Type designation, ratings and serial number of apparatus ;
- Outline description of apparatus (including number of peles , interlocking system, busbar
system, earthing system , and the are extinguishing process );
- Make , type , serial numbers , ratings of essential parts, w here applicable (e.g. operating
mechanisms, interrupters , shunt impedances , relays , fuse links, insulators);
- Rated characteristics of fuse links and protective devices;
- W hether the apparatus is intended for operation in the vertical and horizontal plane.
60694 © IEC:1996+A1:2000+A2:200 1 - 197 -

A.2 Drawings
Drawings to be subm i tted Drawing content (as applicable)
Single-line diagram of main circuit Type designation of principal components
General layout Overall dimensions
Supporting struc ture
NOTE Far an assembly it may be necessary t o Enclosure(s)
provide drawings of the comp lete assembly and of
Pressure -relief devices
each switching device.
Conducting parts of main circuit
Earthing conductors and earthing connecti ons
Electrical c learances:
- to earth, between open contacts
- between pales
Location a nd dimensions of barriers between potes
Location of earthed metallic screens, shutters ar partitions in
relation to live parts
Liquid insul ation level
Location and type designation of insulators
Location a nd type designation of instrument transformers
Detailed drawings of insulators Material
Dimensions (including prof ile and creepage distances)
A rrangement drawings of cable boxes Electric al c learances
Principal d imensions
Terminals
Level ar quantity and specifications of insulant in filled boxes
Cable termination details
Oetailed drawings of parts of the main circuit and Oimensions and material of principal parts
associated components
Cross~sectional view through the axis o f main
and arcing contacts
Travel of moving contacts
Electrical c learance between open contacts
Distance between point of contact separation
and end of travel
Assembly of fi xed and moving contacts
Details of termina1s (dimensions, materials)
ldentity of springs
Material and creepage d istances of insulating parts
Detailed drawings of mechanisms (including Arrangement and identity of main components
coupling and operating mechanisms ) of the kinematic chains to:
- main contacts
- auxiliary switches
- pilot switch es
- position indication
Latching d evice
Assembly of mechanism
lnterlocking devices
ldentity of springs
Control and auxiliary devices
Electrical diaj::nam of auxiliarv and control circuits Tvoe desiQnation of a ll comoonents
(if applicable)
60694 © IEC:1996+A1:2000+A2:200 1 - 199 -

Annex B
(normative )

Determination of the equivalent r.m.s. value of a short-time current during

a short circuit of a given duration

The method illustrated in f igure B.1 shou ld be used to determine the short-time curren!
(see 6.6.2).

The total time 11 of the test is divided into 1O equal parts by v erticals O - O, 1 1 and the
r. m.s. value of the a.c . componen! of the curren! is measured at these v erticals.

These values are designated:

Zo, Z 1 ... Z1 0
w here:

z = x/-./2
and X is the peak v alue of a.c. componen! of curren!.

The equivalen! r.m.s. curren! during the t ime 11 is given by:

lt -_ - 1 [ Za2 + 4 ( z,2 + Z 32 +Z52 + Z72 +Zg2) +2 ( Z22 + Z 42 + Z52 + Za2) + z,o

2 ]
30

The d.c. componen! of curren! represented by CC' is not taken into account.

J
Zo
A'
Zl O

B l-li---ll---l+--l-l---lll---l-l--+-l--+-i--l--l--lll--l--l--l--l-+l+l--.¡..¡..¡#-~il-!-l-l--l-Jl--l-l-l--lll-l--l-Jl--l-l-l-l--+-lll-<--l--l-l-l--+-i--l--lll--l-l--l--l--i--l--l+lll--l--l-.¡..¡..¡-l--J-l--lll--1--1--1-l--l-~
T

B'

o o .1 02 03 0 .4 05 0 .6 0 .7 o.8 09

JEC 319/ 96
AA' Envelopes of current wave.
88'
CC' Displacement of current wave zero line from normal zero line at any instant.
ZO . Z 1O RMS va lue of a.c. component of current at any instant measured from normal zero;
d.c . component is neglected
Xo Peak value of a.c. component of current at instant of initiating short circuit.
BT Duration of short circuit , lt-

Figure B.1 - Determination of s hort-time curren!

60694 © IEC:1996+A1:2000+A2:2001 - 201 -

Annex e
(normative)

Method for the weatherproofing test for outdoor

switchgear and controlgear

The switchgear and controlgear to be tested shall be fully equipped and complete w ith all
covers, screens , bushings, etc., and placed in !he area to be supplied w ith artificial preci-
pitation. For sw itchgear and controlgear comprising several functional units a mínimum of tw o
units shall be used to test the joints between them.

The artificial precipitation shall be supplied by a sufficient number of nozzles to produce a

uniform spray over the surfaces under test. The various parts of the sw itchgear and
controlgear may be tested separately, provided that a uniform spray is simultaneously appl ied
also to both of the followi ng :

a) the top surfaces from nozzles located at a suitable height:

b) the floor outside the equipment for a distance of 1 m in front of !he parts under test w ith
the equipment located at !he mínimum height above the floor level specified by !he
manufacturer.

Where the w idth of the equipment exceeds 3 m , the spray may be appl ied to 3 m w ide
sections in turn. Pressurized enclosures need not be submitted to artificial precipitation.

Each nozzle used for this test shall deliver a square-shaped spray pattern w ith uniform spray
distribution and sha ll have a capacity of 30 I/ m in ± 1O % at a pressure of 460 kPa ± 10 % and
a spray angle of 60º to 80º . The centre lines of the nozzles shall be inclined dow nw ards so
that the top of !he spray is horizontal as it is directed tow ards the surfaces being tested. lt is
convenient to arrange the nozzles on a vertical stand-pipe and to space them about 2 m apart
(see test arrangement in figure C.1 ).

The pressure in the feed pipe of the nozzles shall be 460 kPa ± 1O % under f low conditions.
The rate al w hich w ater is applied to each surface under test shall be about 5 mm/min, and
each surface so tested shall receive this rate of artificial precipitation for a duration of 5 min.
The spray nozzles shall be at a distance between 2,5 m and 3 m from the nearest vertical
surface under test.

NOT E When a nozzle in accorda nce with figure C_2 is used, the quantity of water is considered to be in
accordance with this standard when th e pressure is 460 kPa ± 1O %.

After the test is completed , !he equipment shall be inspected promptly to determine w hether
the following requirements have been met:

1) no w ater shall be visible on the insulation of the main and auxiliary circuits;
2) no w ater shall be v isible on any interna! electrical components and mechanisms of the
equipment;
3) no significan! accumulation of w ater shall be retained by the structure or other non-
insulating parts (to m inimize corrosion ).
60694 © IEC:1996+A 1:2000+A2:200 1 - 203 -

e /E:C J40l'KJ

A About 2 m

8 1m
e 2,5 m to 3 m
D Mínimum height above floor

Figure C.1 - Arrangement for weatherproofing test

60694 <0 IEC: 1996+A1 :2000+A2:2001 - 205-

27,8

15

,. .. ~

¡;¡ g i :!!_
& s ~ &
" &

22,2 16

28
Body
Material: brass 39

14,3 1,6

0 19k7 3 , - 0.2 0,8

Interna! vanes
Material: brass

Assembly

-$ - ,
Scale 1: 1

JEC 141/llt'J

Dimensions in millimetres

Figure C.2 - Nozzle for weatherprooflng test

60694 © IEC:1996+A1:2000+A2:2001 - 207 -

Annex D
(informative )

lnformation about insulation levels and tests

The object of this annex is to give information about the insulation levels and tests specified
in this standard.

D.1 Specification
The rated insulation levels are mainly based on the requirements of IEC 6007 1-1. The
application guide IEC 60071-2 (future third edition) gives every explanation as to the relat ion
between the system nominal voltage and the standardized insu lation levels. But these
standards are designed to be used by all sorts of equ ipment: insulators, cables , pow er
t ransformers, etc. Therefore, sorne choices need to be made applying them to high-voltage
switchgear and controlgear.

D.1.1 Phase-to-earth

The insulation levels have been selected taking into account the values most used for
sw itchgear and controlgear.

In addition to IEC 60071-1 , a rated short-duration power-frequency w ithstand voltage is added

for rated voltages higher than 245 kV, in order to check the withstand of temporary
overvoltages by interna! insu lation.

D.1.2 Phase-to-phase

No changes are made to the specifications of IEC 60071 - 1 for the insulation betw een poles.

D.1.3 Longitudinal insulation

Since no other IEC product standards specify longitudina l insulation , the rated w ithstand
values need not be taken from the list of IEC 60071- 1.

D.1 .3. 1 lso lating distance

In addition t o the requirements of insulation coordination, the standard specifies insulation of

t he "isolating distance" . This is to cover special cond itions w hich are to be met by
disconnectors to provide an additional safety factor ( 1, 15) (see 5. 102 of IEC 60129).

The intent is not to provide "auto-coordination" which wou ld require that any disrupt ive
discharge occurs phase-to-earth on the switching device rather than between its open
contacts. lt is generally recognized that wh en work has to be carried out on a high-voltage
conductor, safety is insured only when the conductor is connected to earth. Local safety rules
shall apply.

D.1.3.2 Combined voltage tests of tables 2

A combined voltage test is one in w hich tw o separate sources, generating voltages against
earth , are connected to two terminals of the test object (see clause 26 of IEC 60060-1 ).

Such a test is required for switchgear and controlgear of 300 kV and above to account for out-
of-phase conditions across the isolating distances or for coupling circuit- breakers. lt may also
be useful to perform any test w here the test voltage betw een two live parts is specified higher
t han phase-to-earth .
60694 © IEC:1996+A1:2000+A2:2001 - 209 -

The components of !he combined voltage tests have been specified after !he following
considerations:

- Short-duration power-frequency withsfand volfage

The specified power-frequency w ithstand voltage values correspond to !he most severe
situation of full load rejection after disconnection of a generator al full load . The over-
voltage on !he generator side of !he sw itching device may reach up to 1,5 times
!he system voltage and may last up to 3 s w ith possible phase shift. Al !he same time, !he
netw ork side of !he sw itc hing device is energized al !he norma l operating voltage.
The sum of !he two voltages in phase opposition is 2 ,5 times !he system voltage , extended
here to 2 ,5 !he rated voltage.

- Swifching impulse withsfand voltage

The sw itching impulse voltage value specified phase to earth in column 4 of table 2 is
designed to cover !he highest slow-front overvoltage likely to occur al !he sw itching device
terminal. This occurs al !he remole end of a line after fas! reclosing f rom !he other end on
a trapped charge. This highest overvoltage is of !he same pola rity as !he pow er-frequency
voltage of !he netw ork al this instan! and therefore is no! to be retained w hen !he
maximum stress across a switching device is looked far. The maximum stress takes place
w hen an overvoltage occurs on !he polarity opposite to !he pow er-frequency voltage of !he
system. The maximum value in this case is !he one occurring on closing from !he remole
end , w hich is low er !han !he one occurring on reclosing. Therefore, !he values of sw itching
impulse specified in column 6 are lower !han !hose of column 4.

- Lightning impulse
In !he process of designing insulation coordination, IEC 60071-1 takes into account !he
probability of occurrences of a situation to choose !he performance criteria. The likelihood
that !he maximum fast-front overvoltage occu rs o n !he terminal of a switching device al
!he instan! w hen its opposite terminal is energized with !he maximum system voltage
al opposite polarity is small. Therefore , !he specified lightning impulse to be considered in
this particular case need no! be as high as far !he general case. A reduction of about 5 %
has been preved more !han adequate during !he las! decades. Far convenient testing, this
reduction of !he total voltage across !he switching device is applied to !he pow er-
frequency voltage componen!.

D.2 Testing
D.2.1 Test of the longitudinal insulation with the alternative method

To be strictly equivalen! to !he preferred method, !he voltage betw een !he energized terminal
and !he frame should be equa l to the rated withstand voltage phase to earth. But it is difficult
to adjust exactly this voltage simultaneously w ith !he longitudinal test voltage. The value of U1
has been fixed considering !he follow ing facts:

- !he test voltage betw een any terminal and the frame cannot exceed !he rated phase to
earth w ithstand voltage w ithout risk;
- the electric f ield stress across open contacts is mainly dependan! on the voltage across
them, and to a lesser extent on the voltage to earth ;
- !he determination of the rated w ithstand voltage of the isolating distance is no! so
acc urate ;
- safety factor is included in the process of insulation coordination (see IEC 60071-1 ); to
account far such testing difficulties.
60694 © IEC:1996+A1:2000+A2:2001 - 211 -

D.2.2 Test between phases for rated voltages above 245 kV

D.2.2.1 Voltage share between the two switching impulse components

of the phase-to-phase test

The actual ratio of the two components may have any value on the network. In order to
simplify the tests IEC 60071-1 decided to specify balanced components (same amplitude w ith
opposite polarities). Since this leads to a less severe condition , the total test voltage w as
increased to cover any real istic case (see annex C of IEC 60071 -2). So if the same total test
voltage is applied by an unbalanced share of the components, the test is more difficult !han
required.

But few laboratories have two impulse generators. So one componen! may be replaced by the
peak of a power-frequency voltage. But this leads to pow er-frequency voltages higher !han
specified phase-to-earth , and for a rather long duration. Therefore, sorne compromise is
necessary depending on the actual phase-to-earth w ithstand voltage of the sw itch ing device
and on the laboratory's facilities.

D.2.2.2 Wet tests

No wet switching impulse tests are normally necessary betw een phases for the following
reasons:

- enclosed insulation does not need w et tests;

- insulation between phases exposed to w eather precipitations is only atmospheric air, the
w ithstand voltage of w hich is not sensitive to th is influence for sw itchgear and controlgear
of rated voltage above 245 kV.

D.2.3 Combinad voltage tests of longitudinal insulation

D.2.3.1 Tolerance on the power-frequency voltage componen!

According to IEC 60060-1, the tolerance of the power-frequency componen! voltage should be
maintained within 3 % of the specified level. This allows for sorne variations from the main
voltage w ithout permanent adjustment. But during a combined voltage test, the laboratory has
also to monitor many other parameters from the impulse voltage source. Therefore a higher
tolerance is acceptable for t his componen!, but the test voltage to be considered is the actual
total voltage across the open contacts or the isolating distance.

D.2.3.2 Atmospheric correction factor

The atmospheric correction factor should be calculated according to IEC 60060-1. In the case
of combined voltage test, the atmospheric correction factor should be applied to the total test
voltage , w hich is the sum of the two components.
60694 © IEC:1996+A1:2000+A2:2001 - 2 13 -

Annex E
(informative )

Tightness (information, example and guidance)

Example:
Gas- insulated metal-enc losed switchgear,
single-p hase encapsulated, circuit-
breaker compartments of the three
phases connected to the same gas-
system.

Jt;C 1, 219f,

Leakage rate of the system:

Compartment A 19 · 10- 6 Pa m 3/ s

Compartment B 19 · 10-6 Pa . m 3/ s
Compartment C 19 · 10-6 Pa . m 3/ s
Control box D (including v alves, gauges, monitoring devices) 2,3 · 10- 6 Pa . m 3/s

Piping e 0,2 -10-6 Pa . m 3/ s

Piping f 0,2 -10-6 Pa - m 3/s
Piping g 0,2 -10-6 Pa - m 31s
Compl ete system 59,9 -10- 6 Pa - m 3/s

Filling pressure Pre: 700 kPa (absolute)

Alarm pressure Pae: 640 kPa (absolute)

Total interna! volume 270 dm3

43
59,9·10 · 60 · 60 · 24 · 365
F,el - - - - - - - , - - - - - , , - - . 100 = 1,0 % per year
3 3
700 · 10 · 270 . 10-

(700 - 640) 10 3 . 270. 10- 3

T = - - - - - - - - - - - - = 8,5 years
43
59,9 · 10 60 · 60 · 24 · 365

Figure E.1 - Example of a tightness coordination chart, TC,

for closed pressure systems
 a,
Leak Hatogen M ass o
a,
senaitivity

3
rme tor
1 kg SF,
to ktak
Uhrasonic
Pressure
loss
Soap a~ ution
dyo1
Fleme torch
Thermal
conductivit y
A mmonia
detectors Elecu on
c apture
detector
spectroscopy
...
<D

@
Pa x cm / s
m
()
10' 18days
<D
10• 24 weeks <D
a,
+
10• 5 years Any gas ~
N
10
1
48years o
o
o
Any g aa for Freon 12 +
10° 480 years )>
bubble t est SF,
N
10-1 4 800 years ¡._:,
o
o
~
10-• 48000 years NH3

10-• 480 000 years

Freon 12 SF, Any gas N

~
u,
(n ote 1) (note 1) (note 2) (note 3 )
1
~ Applicable
11:C J ,lj/WJ

~ Limit ot a pplicability

NOTE 1 Sniffing in good conditions . By integrated leakage measurement, better sensitivity can be achieved.
NOTE 2 By integrat ed leakage measurement.
NOTE 3 By s niffing

Figure E.2 - Sensitiv lty and appllcablllty of dlfferent leak detectio n methods for tlghtness test s
60694 © IEC:1996+A1:2000+A2:2001 - 217 -

Annex F
(informative)

Dielectric testing of self-protected switchgear and controlgear

F.1 General

F.1.1 W hen sw itchgear and controlgear include surge-arresters mixed with other pieces of
equipment having w ithstand voltage rating w ithout possible separation, sorne adaptations to
the normal testing practices are needed.

Firstly, it is necessary to introduce a "prospective w ithstand voltage", the test voltage which
would have been supplied by the impulse generator without the influence of the test object. lt
is to be measured befare connecting the test object.

Then a failure criterion is to be defined: the "abnormal" discharge w hich is show n by a sudden
step-dow n on the voltage-time recording , or w hich has a shape different from the shape of the
voltage across the voltage-limiting device tested separately (see figu re F.1 ).

F.1.2 The short-duration power-frequency w ithstand voltage has also to be considered,

specially for sw itchgear and controlgear having a rated voltage of 245 kV and below.

For this range of equipment, the value of the pow er-frequency test voltage is high , not
because of so high temporary overvoltages, but rather to cover also the w ithstand of slow-
front class overvoltages.

Keeping this test voltage shape and duration at the levels specified in tables 1 and 2 w ould
damage the surge-arresters without representing realistic service conditions. Therefore ,
pow er-frequency tests shall be performed at levels covering the actual possible temporary
overvoltages and sw itching impulses shall be added to check the insulation against slow front
overvoltages (see IEC 6007 1-2 ).

F.1.3 Voltage-lim iting devices included in self-protected sw itchgear and controlgear shall be
separately tested accord ing to their relevan! standard (I EC 60099).

The purpose of the tests of this annex is to check the coordination betw een voltage-l imit ing
devices and other components of the sw itchgear and controlgear.

F.2 Power-frequency tests

Dry pow er-frequency tests shal l be performed for 1 min at r.m.s. test voltages as below . No
disruptive discharges shall occur. An earth-fault factor of 1,4 has been used in the following
formulae as a general figure. Actual values should be used w hen these are know n.

F .2.1 Phase-to-earth

- sw itchgear and controlgear to be used on solidly earthed systems shall be tested

at 1,4 1,15 uJ,13 = 1,6 u,/-./3 .
- sw itchgear and controlgear to be used on systems other than solidly earthed shall be
tested at 1, 15 u, = u,/-./3.
2
60694 © IEC:1996+A1:2000+A2:2001 - 219 -

F.2.2 Between phases

- sw itchgear and controlgear without c onductive earthed partitions betw een phases shall be
tested at 1, 15 u, =2 u,/../3.
F.2.3 Across the open switching device
- sw itchgear and controlgear to be used on solidly earthed systems sh all be tested
at 1, 15 ( 1+1 ,4) u,/../3 = 2,75 u, /../3
- sw itchgear and controlgear to be used on systems other than solidly earthed shall be
tested at 1, 15 ( 1 + ../3) u,/../3
= 3,15 u,/../3
- across the isolating distance , the test shall be 1, 15 times the test vo ltage across the open
sw itching device.

The test shall be performed with two voltage sources in opposition, one being set near the
test voltage value phase-to-earth, and the other al a conven ient value to give the total
specified value.

As an alternative , a single voltage source may be used if the frame is insulated from earth. In
that case, the voltage betw een the energized termina l and the frame should be fixed near the
test voltage value phase-to-earth, as in alternative method of 6.2.5.2 b) .

F.3 Switching impulse tests

Sw itchgear and controlgear of rated voltages 300 kV and above shall be tested w ith test
voltages as in tables 2, as prospective voltages.

Sw itchgear and controlgear of rated voltage 245 kV and below shall be tested w ith 15
sw itching impulses , in each polarity and in each condition. No disruptive discharges shall
occur. The prospective peak test voltage shall be 1,55 times the r .m.s. pow er frequency
voltages specified in table 1 betw een phase and earth , betw een phases, between open
sw itching devices and across the isolati ng distance respectively, if any.

The actual voltage across the test object shall be recorded , al leas! phase-to-earth. The
actual voltage shape may be very different from the prospective voltage shape, due to
the respective characteristics of the test generator and of the voltage-limiting device (see
figure F.1 ) .

F.4 Lightning impulse tests

Sw itchgear and controlgear shall be tested w ith test voltages as in tables 1, and 2 , as
prospective voltages.
60694 © IEC:1996+A1:2000+A2:2001 - 221 -

F. 5 Routine tests

Components to be incorporated into self-protected sw itchgear and controlgear shall be tested

far 1 min w ith a pow er-frequency voltage r.m.s. v alue equal to 1, 15 O, 7 of th e value of the
peak of t he actual limited voltage U 1 measured during the type test w ith sw itching impulses.

, .,... -............ ..
,
,, A - ~ v e _::_~ .......
\dta;¡e -

1,
o 'I
lcgl
18031495

U1 Actual voltage

Ux Various shapes of disruptive voltage

Figure F .1 - Examples of impulse v oltage shapes with

incorporated voltage-limiting devices
60694 © IEC:1996+A1:2000+A2:200 1 - 223 -

Annex G
(info rmative )

Bibliography

The following lnternational Standards are referred to in this standard for information.

IEC 60068-2-6: 1995, Environmental testing - Part 2: Tests - Test Fe: Vibration (sinusoidal)

IEC 60099-4: 1991, Surge-arresters - Part 4: Metal-oxide surge arresters without gaps for a.c.
systems

IEC 60129: 1984 , Alternating curren/ disconnectors (isolators) and earthing switches

IEC 60233: 1974 , Tests on hollow insulators for use in electrical equipment

IEC 60273: 1990, Characteristics of indoor and outdoor post insulators for systems with
nominal voltages greater than 1 000 V

IEC 60664- 1: 1992, lnsulation coordina/ion for equipment within low- voltage systems - Par/ 1:
Principies, requirements and tests

IEC 60721 -2-2: 1988, Classification of environmental conditions - Part 2: Environmental

conditions appearing in nature - Precipita/ion and wind

IEC 60721 -2-4 :1987, Classification of environmental conditions - Part 2: Environmental

conditions appearing in nature - Solar radiation and temperature

IEC 60721-3-3: 1994, Classification of environmental conditions - Part 3: Classification of

groups of environmental parameters and their severities - Section 3: Stationary use al
weatherprotected locations

IEC 60721-3-4 : 1995, Classification of environmental conditions - Part 3: Classification of

groups of environmental parameters and their severities - Section 4: Stationary use at non-
weatherprotected locations

IEC 60943 :1989, Guide for the specification of permissible temperature and temperature rise
for parts of electrical equipment, in particular for terminals

IEC 61000-4-1: 1992, Electromagnetic compatibility (EMC) - Part 4: Testing and measurement
techniques - Section 1: Overview of immunity tests - Basic EMC publica/ion

ISO 9001:1994, Quality systems - Model for quality assurance in design, development,
production, insta/la/ion and servicing

ISO 9002: 1994, Quality systems - Model for quality assurance in production, installation and
servicing
60694 © IEC:1996+A1:2000+A2:2001 - 225 -

Annex H
(informative)

Electromagnetic compatibility site measurements

EMC site measurements are not type tests , but may be performed in special situations:

- where it is deemed necessary to verify that actual stresses are covered by the EMC
severity class of the secondary system , or
- in order to evaluate the electromagnetic environment, in order to apply proper mitigation
methods , if necessary,
- to record the electromagnetically induced voltages in a secondary system , due to
sw itching operations both in the main circuit and in the secondary system . lt is not
considered necessary to test all secondary systems in a substation under consideration.
A typical configuration should be chosen.

Measurement of the induced voltages are to be made al representative ports in the interface
between the secondary system and the surrounding netw ork, for example, at the input
terminals of control cubicles , without disconnection of the system. The extension of the
secondary system is described in 5.18. lnstrumentation for recording induced voltages should
be connected as outlined in IEC 60816.

Sw itching operations should be carried out at normal operating voltage, both in the main
circuit and in the secondary system. lnduced voltages w ill vary statistically, and thus a
representative number of both making and breaking operations should be chosen, with random
operating instants.

The sw itching operations in the main c ircuit are to be made under no-load conditions. The
tests w ill thus include the switching of parts of the substation , but no switching of load
currents and no fau lt currents.

The making operations in the main circuit should be performed with trapped charge on the
load side corresponding to normal operating voltage. This condition may be difficult to obtain
at testing, and , as an alternative, the test procedure may be as follows:

- discharge the load side before the making operation , to assure that the trapped charge is
zero;
- multiply recorded voltage values at the making o peration by 2, in order to simulate the
case w ith trapped charge on the load side.

The sw itching device in the primary system shall preferably be operated at rated pressure and
auxiliary voltage.

NOTE 1 The most severe cases, with regard to induced voltages, will normally occur when only a small part of a
substation is switched
NOTE 2 Especially fa r GIS installations, the most severe e lectromagnetic disturbances are exp ec ted to occur at
disconnector switching

The recorded or calculated peak value of induced common mode voltage, due to sw itching
in the main circuit, should not exceed 1,6 kV for interfaces of normal EMC severity class ,
and 0,8 kV for interfaces of reduced EMC severity class.

The note of 5.18 gives guidelines for improvement of the electromagnetic compatibility.
 1111 Staoda,ds S"'vey

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 ISBN 2-8318-5937-9

ICS 29.130.10
,JL !Jl
Typeset and printed by the IEC Central Office
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