IEC 62271-104:2015

IEC 62271-104 ®
Edition 2.0 2015-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
High-voltage switchgear and controlgear –
Part 104: Alternating current switches for rated voltages higher than 52 kV

Appareillage à haute tension –
Partie 104: Interrupteurs à courant alternatif pour tensions assignées
supérieures à 52 kV
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IEC 62271-104 ®
Edition 2.0 2015-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
High-voltage switchgear and controlgear –

Part 104: Alternating current switches for rated voltages higher than 52 kV

Appareillage à haute tension –

Partie 104: Interrupteurs à courant alternatif pour tensions assignées

supérieures à 52 kV
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.130.10; 29.130.99 ISBN 978-2-8322-2245-4

– 2 – IEC 62271-104:2015  IEC 2015
CONTENTS
FOREWORD . 6
1 General . 8
1.1 Scope . 8
1.2 Normative references . 9
2 Normal and special service conditions . 9
3 Terms and definitions . 9
3.1 General terms . 9
3.2 Assemblies . 9
3.3 Parts of assemblies . 9
3.4 Switching devices . 10
3.6 Operation . 11
3.7 Characteristic quantities . 11
4 Ratings . 13
4.1 Rated voltage (U ) . 13
r
4.2 Rated insulation level . 13
4.3 Rated frequency (f ) . 13
r
4.4 Rated normal current and temperature rise (I ) . 13
r
4.5 Rated short-time withstand current (I ) . 13
k
4.6 Rated peak withstand current (I ) . 13
p
4.7 Rated duration of short-circuit (t ) . 13
k
4.8 Rated supply voltage of closing and opening devices and of auxiliary and
control circuits (U ) . 13
a
4.9 Rated supply frequency of closing and opening devices and of auxiliary
circuits . 13
4.10 Rated pressure of compressed gas supply for controlled pressure systems . 14
4.11 Rated filling levels for insulation and/or operation . 14
4.101 Rated earth fault breaking current . 14
4.102 Rated short-circuit making current . 14
4.103 Rated mainly active load-breaking current . 14
4.104 Rated closed-loop breaking current . 14
4.105 Rated capacitive switching currents . 14
4.105.1 Rated line-charging breaking current . 14
4.105.2 Rated cable-charging breaking current . 14
4.105.3 Rated single capacitor bank breaking current . 14
4.105.4 Rated back-to-back capacitor bank breaking current . 14
4.105.5 Single capacitor bank inrush making current . 15
4.105.6 Rated back-to-back capacitor bank inrush making current . 15
4.105.7 Rated cable and line-charging breaking current under earth fault
conditions . 15
4.106 Inductive load switching . 15
4.106.1 Shunt reactor breaking current . 15
4.106.2 Rated no-load transformer breaking current . 15
4.107 Rated mechanical terminal load . 15
4.108 Coordination of rated values for a general-purpose switch . 15
4.109 Coordination of rated values for limited-purpose and special-purpose
switches . 16

5 Design and construction . 16
5.1 Requirements for liquids in high-voltage switches . 16
5.2 Requirements for gases in high-voltage switches . 16
5.3 Earthing of high-voltage switches . 17
5.4 Auxiliary and control equipment . 17
5.5 Dependent power operation . 17
5.6 Stored energy operation . 17
5.7 Independent manual or power operation (independent unlatched operation) . 17
5.8 Operation of releases . 17
5.9 Low- and high-pressure interlocking and monitoring devices . 17
5.10 Nameplates . 17
5.11 Interlocking devices . 18
5.12 Position indication . 19
5.13 Degree of protection provided by enclosures. 19
5.14 Creepage distances for outdoor insulators . 19
5.15 Gas and vacuum tightness . 19
5.16 Liquid tightness . 19
5.17 Fire hazard (flammability) . 19
5.18 Electromagnetic compatibility (EMC) . 19
5.19 X-ray emission . 19
5.20 Corrosion . 19
5.101 Closing mechanism . 19
5.102 Mechanical strength . 19
5.103 Position of the movable contact system and its indicating or signalling device . 19
5.103.1 Securing the position . 19
5.103.2 Indication of position . 20
5.103.3 Auxiliary contacts for signalling . 20
6 Type tests . 20
6.1 General . 20
6.2 Dielectric tests . 21
6.3 Radio interference voltage (r.i.v.) tests . 22
6.4 Measurement of the resistance of circuits . 22
6.5 Temperature rise tests . 22
6.6 Short-time withstand current and peak withstand current tests . 22
6.7 Verification of the protection . 22
6.8 Tightness tests . 22
6.9 Electromagnetic compatibility tests (EMC) . 22
6.10 Additional tests on auxiliary and control circuits . 22
6.11 X-radiation test procedure for vacuum interrupters . 22
6.101 Mechanical operation tests . 22
6.101.1 Arrangement of the switch for tests . 22
6.101.2 Tests for general-purpose switches . 23
6.101.3 Tests for limited-purpose and special-purpose switches . 24
6.101.4 Condition of switch during and after mechanical operation tests . 24
6.101.5 Operation under severe ice conditions . 24
6.101.6 Static terminal load tests . 24
6.102 Miscellaneous provision for making and breaking tests . 25
6.102.1 Arrangement of the switch for tests . 25

– 4 – IEC 62271-104:2015  IEC 2015
6.102.2 Behaviour of switch during breaking tests . 26
6.102.3 Condition of switch after breaking tests . 26
6.102.4 Condition of switch during and after short-circuit making tests . 26
6.103 Test circuits for making and breaking tests . 27
6.103.1 General . 27
6.103.2 Earthing of test circuit and switch . 27
6.103.3 Mainly active load circuit (test duty 1 and test duty 3) . 28
6.103.4 Closed-loop circuits (test duty 2) . 31
6.103.5 Test circuits for short-circuit making tests (test duty 6) . 35
6.103.6 Test circuits for breaking tests under earth fault conditions (test duties
7a and 7b) . 37
6.104 Test quantities . 37
6.104.1 Test frequency . 37
6.104.2 Test voltage for breaking tests . 37
6.104.3 Breaking current . 38
6.104.4 Test voltage for short-circuit making tests . 39
6.104.5 Short-circuit making current. 40
6.105 Capacitive current switching tests . 40
6.105.1 Applicability . 40
6.105.2 General . 41
6.105.3 Characteristics of supply circuits . 41
6.105.4 Earthing of the supply circuit . 41
6.105.5 Characteristics of the capacitive circuit to be switched . 41
6.105.6 Waveform of the current . 41
6.105.7 Test voltage . 41
6.105.8 Test current . 42
6.105.9 Test duties . 42
6.105.10 Tests with specified TRV . 43
6.105.11 Criteria to pass the test . 43
6.106 Inductive load switching (test duty 5) . 43
6.106.1 No-load transformer circuit (test duty 5a) . 43
6.106.2 Shunt-reactor current switching tests (test duty 5b) . 43
6.107 Tests for general-purpose switches . 44
6.108 Tests for limited-purpose switches . 45
6.109 Tests for special-purpose switches . 45
6.110 Type test reports . 45
7 Routine tests . 46
7.1 Dielectric tests on main circuit . 46
7.2 Tests on auxiliary and control circuits . 46
7.3 Measurement of the resistance of the main circuit . 46
7.4 Tightness test . 46
7.5 Design and visual checks . 46
7.101 Mechanical operating tests . 46
8 Guide to the selection of high-voltage switches . 47
8.1 Selection of rated values . 47
8.2 Continuous or temporary overload due to changed service conditions . 47
8.101 General . 47
8.102 Conditions affecting application . 47

8.103 Insulation coordination . 47
9 Information to be given with enquiries, tenders and orders . 48
9.1 Information with enquiries and orders . 48
9.2 Information with tenders . 48
10 Transport, storage, installation, operation and maintenance. 48
11 Safety . 48
12 Influence of the high-voltage switch on the environment . 48
Bibliography . 49

Figure 1 – Single-phase test circuit for mainly active load current switching for test
duties 1 and 3 . 28
Figure 2 – Single-phase test circuit for transmission line closed loop and parallel-
transformer current switching test, for test duties 2a and 2b . 28
Figure 3 – Three-phase test circuit for mainly active load current switching, for test
duties 1 and 3 . 29
Figure 4 – Supply and load side transient for mainly active load current switching tests
(see Table 4) . 30
Figure 5 – Three-phase test circuit for transmission line closed loop and parallel-
transformer current switching test for test duties 2a and 2b . 31
Figure 6 – Illustration of the transient associated with transmission line closed loop
current breaking tests (see Table 5) . 33
Figure 7 – Three-phase test circuit for short circuit making current test for test duty 6 . 36
Figure 8 – Single-phase test circuit for short circuit making current test for test duty 6 . 36

Table 1 – Preferred values of line- and cable-charging breaking currents for a general-
purpose switch . 16
Table 2 – Nameplate information . 18
Table 3 – Type tests . 21
Table 4 – Supply circuit TRV parameters for mainly active load current breaking tests . 30
Table 5 – TRV parameters for transmission line closed loop current breaking tests . 32
Table 6 – Test duties for single-phase tests on three-pole switches having a non-
simultaneity between poles of 0,25 cycle or less . 33
Table 7 – Test duties for single-phase tests on three-pole switches having more than
0,25 cycle non-simultaneity and switches operated pole after pole . 34
Table 8 – TRV parameters for parallel transformer current breaking tests. 35
Table 9 – Test duties for three-phase tests on three-pole switches . 37

– 6 – IEC 62271-104:2015  IEC 2015
INTERNATIONAL ELECTROTECHNICAL COMMISSION
______________
HIGH-VOLTAGE SWITCHGEAR AND CONTROLGEAR –

Part 104: Alternating current switches
for rated voltages higher than 52 kV

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
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5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
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6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 62271-104 has been prepared by subcommittee 17A: High-voltage
switchgear and controlgear, of IEC technical committee 17: Switchgear and controlgear.
This second edition replaces and cancels the first edition published in 2009 and constitutes a
technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
• the title was changed such that the voltage range now is >52 kV instead of ≥52 kV;
• the references have been updated;
• the comments in 17A/1063/RVC have been addressed.

The text of this standard is based on the following documents:
FDIS Report on voting
17A/1079/FDIS 17A/1082/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
This standard is to be read in conjunction with IEC 62271-1 (2007), IEC 62271-100 (2008),
IEC 62271-102 (2001) and IEC 62271-110 (2012). In order to simplify the indication of
corresponding requirements, the same numbering of clauses and subclauses is used as in
IEC 62271-1. Modifications to these clauses and subclauses are given under the same
numbering, whilst additional subclauses are numbered from 101.
A list of all parts in the IEC 62271 series, published under the general title High-voltage
switchgear and controlgear, can be found on the IEC website.
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
– 8 – IEC 62271-104:2015  IEC 2015
HIGH-VOLTAGE SWITCHGEAR AND CONTROLGEAR –

Part 104: Alternating current switches
for rated voltages higher than 52 kV

1 General
1.1 Scope
Subclause 1.1 of IEC 62271-1:2007 is not applicable, and is replaced as follows:
This part of IEC 62271 is applicable to three-pole alternating current switches for rated
voltages higher than 52 kV, having making and breaking current ratings, for indoor and
outdoor installations, and for rated frequencies up to and including 60 Hz.
This standard is also applicable to the operating devices of these switches and to their
auxiliary equipment.
NOTE 1 Switches for gas insulated switchgear are covered by this standard.
NOTE 2 Switches having a disconnecting function and called switch-disconnectors are also covered by IEC 62271-
102.
NOTE 3 Earthing switches are not covered by this standard. Earthing switches forming an integral part of a switch
are covered by IEC 62271-102.
The main object of this standard is to establish requirements for switches used in
transmission and distribution systems. General-purpose switches for this application are
designed to comply with the following service applications:
– arrying rated normal current continuously;
– carrying short-circuit currents for a specified time;
– switching of mainly active loads;
– switching of no-load transformers;
– switching of the charging current of unloaded cables, overhead lines or busbars;
– switching of closed-loop circuits;
– making short-circuit currents.
A further object of this standard is to establish requirements for limited-purpose and special-
purpose switches used in transmission and distribution systems.
Limited-purpose switches comply with one or more of the service applications indicated
above.
Special-purpose switches may comply with one or more of the service applications indicated
above and, in addition, are suitable for one or more of the following applications:
– switching single capacitor banks;
– switching back-to-back capacitor banks;
– switching shunt reactors including secondary or tertiary reactors switched from the primary
side of the transformer;
– applications requiring an increased number of operating cycles;
– switching under earth fault conditions in non-effectively earthed neutral systems.

1.2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and
are indispensable for its application. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 60050-441:1984, International Electrotechnical Vocabulary – Chapter 441: Switchgear,
controlgear and fuses
IEC 60071 (all parts), Insulation co-ordination
IEC 60071-1, Insulation co-ordination – Part 1: Definitions, principles and rules
IEC 60270, High-voltage test techniques – Partial discharge measurements
IEC 62271-1:2007, High-voltage switchgear and controlgear – Part 1: Common specifications
IEC 62271-1:2007/AMD1:2011
IEC 62271-100:2008, High-voltage switchgear and controlgear – Part 100: Alternating-current
circuit-breakers
IEC 62271-100:2008/AMD1:2012
IEC 62271-102:2001, High-voltage switchgear and controlgear – Part 102: Alternating current
disconnectors and earthing switches
IEC 62271-102:2001/AMD1:2011
IEC 62271-102:2001/AMD2:2013
IEC 62271-110:2012, High-voltage switchgear and controlgear – Part 110: Inductive load
switching
2 Normal and special service conditions
Clause 2 of IEC 62271-1:2007/AMD 1:2011 is applicable.
3 Terms and definitions
Clause 3 of IEC 62271-1:2007 is applicable with the the following additions.
For the purposes of this document, definitions of general terms are based on IEC 60050-441
and IEC 60071-1.
Additional terms and definitions are based solely on IEC 60050-441.
3.1 General terms
Subclause 3.1 of IEC 62271-1:2007 is applicable.
3.2 Assemblies
Subclause 3.2 of IEC 62271-1:2007 is applicable.
3.3 Parts of assemblies
Subclause 3.2 of IEC 62271-1:2007 is applicable.

– 10 – IEC 62271-104:2015  IEC 2015
3.4 Switching devices
Subclause 3.4 of IEC 62271-1:2007 is applicable, with the following additions.
3.4.101
switch
switching device capable of making, carrying and breaking currents under normal circuit
conditions, which may include specified operating overload conditions and also carrying for a
specified time currents under specified abnormal circuit conditions, such as those of short-
circuit
[SOURCE: IEC 60050-441:1984, 441-14-10, modified – deletion of the word "mechanical" in
the definition and deletion of the note.]
3.4.102
switch-disconnector
switch which, in the open position, satisfies the isolating requirements specified for a
disconnector
[SOURCE: IEC 60050-441:1984, 441-14-12]
3.4.103
general-purpose switch
switch capable of performing, with currents up to its rated breaking currents, all making and
breaking operations which may normally occur; capable of carrying and making short-circuit
currents
Note 1 to entry: Refer to 4.108 for specific ratings of a general-purpose switch.
3.4.104
limited-purpose switch
switch which complies with one or more, but not with all, service applications of a general-
purpose switch
3.4.105
special-purpose switch
switch suitable for switching requirements other than those specified for a general-purpose
switch
Note 1 to entry: Examples of such requirements are capacitor bank switching, shunt reactor switching, switching
under earth fault conditions, and a capability of an increased number of operating cycles.
3.4.106
class C1 switch
special-purpose switch with low probability of restrike during capacitive current breaking as
demonstrated by specific type tests
3.4.107
class C2 switch
special-purpose switch with very low probability of restrike during capacitive current breaking
as demonstrated by specific type tests
3.4.108
single capacitor bank switch
special-purpose switch intended for switching of a single capacitor bank with charging
currents up to its rated single capacitor bank breaking current

3.4.109
back-to-back capacitor bank switch
special-purpose switch intended for breaking capacitor bank-charging currents, with one or
more capacitor banks connected to the bus or supply side of the switch, up to its rated back-
to-back capacitor bank breaking current
3.4.110
shunt reactor switch
special-purpose switch intended for switching a shunt reactor, including secondary or tertiary
reactors switched from the primary side of the transformer
3.5 Parts of switches
Subclause 3.5 of IEC 62271-1:2007 is applicable.
3.6 Operation
Subclause 3.6 of IEC 62271-1:2007 is applicable.
3.7 Characteristic quantities
Subclause 3.7 of IEC 62271-1:2007 is applicable, with the following additions.
3.7.101
breaking capacity (of a switching device or a fuse)
value of prospective current that a switching device or a fuse is capable of breaking at a
stated voltage under prescribed conditions of use and behaviour
Note 1 to entry: The voltage to be stated and the conditions to be prescribed are dealt with in the relevant
publications.
Note 2 to entry: For switching devices, the breaking capacity may be termed according to the kind of current
included in the prescribed conditions, e.g. line-charging breaking capacity, cable charging breaking capacity, single
capacitor bank breaking capacity, etc.
[SOURCE: IEC 60050-441:1984, 441-17-08]
3.7.102
mainly active load breaking capacity
breaking capacity when opening a mainly active load circuit in which the load can be
represented by resistors and reactors in parallel
3.7.103
no-load transformer breaking capacity
breaking capacity when opening a no-load transformer circuit
3.7.104
closed-loop breaking capacity
breaking capacity when opening a closed transmission line loop circuit, or a transformer in
parallel with one or more transformers, i.e. a circuit in which both sides of the switch remain
energized after breaking, and in which the voltage appearing across the terminals is
substantially less than the system voltage
3.7.105
cable-charging breaking capacity
breaking capacity when opening a cable circuit at no load
3.7.106
line-charging breaking capacity
breaking capacity when opening an overhead line circuit at no load

– 12 – IEC 62271-104:2015  IEC 2015
3.7.107
busbar charging breaking capacity
breaking capacity when opening a busbar circuit at no load
3.7.108
single capacitor bank breaking capacity
breaking capacity when opening a single capacitor bank circuit connected to a supply that
does not include another capacitor bank adjacent to the bank being switched
3.7.109
back-to-back capacitor bank breaking capacity
breaking capacity when opening a capacitor bank circuit connected to a supply that includes
one or more capacitor banks adjacent to the bank being switched
3.7.110
capacitor bank inrush making current
high frequency and high magnitude current occurring when closing a capacitor bank circuit
onto a supply including one or more capacitor banks adjacent to the bank being switched
Note 1 to entry: The frequency and magnitude of the inrush current depend upon the values of capacitance and
the values of the inductance between the capacitor banks.
3.7.111
shunt reactor breaking capacity
breaking capacity when opening a shunt reactor circuit, including secondary or tertiary
reactors switched from the primary side of the transformer
3.7.112
earth-fault breaking capacity
breaking capacity in the faulty phase of a non-effectively earthed neutral system when
clearing an earth fault on an unloaded cable or overhead line on the load side of the switch
3.7.113
cable and line charging breaking capacity under earth fault conditions
breaking capacity in the sound phases of an effectively earthed neutral or non-effectively
earthed neutral system when switching off an unloaded cable or overhead line, with an earth
fault on the supply side of the switch
3.7.114
breaking current (of a switching device or a fuse)
current in a pole of a switching device or in a fuse at the instant of initiation of the arc during a
breaking process
[SOURCE: IEC 60050-441:1984 441-17-07]
3.7.115
(peak)-making current
peak value of the first major loop of the current in a pole of a switch during the transient
period following the initiation of current during a making operation
Note 1 to entry: The peak value may differ from one pole to another and from one operation to another as it
depends on the instant of current initiation relative to the wave of the applied voltage.
Note 2 to entry: Where, for a polyphase circuit, a single value of (peak) making current is referred to, it is, unless
otherwise stated, the highest value in any phase.
3.7.116
short-circuit making capacity
making capacity for which the prescribed conditions include a short-circuit at the terminals of
the switching device
[SOURCE: IEC 60050-441:1984, 441-17-10]
3.7.117
simultaneity between poles
maximum difference between the instant of contact touch in the first pole and the last pole
when closing and the maximum time difference between the instant of contact separation
between the first pole and the last pole when opening
4 Ratings
Clause 4 of IEC 62271-1:2007/AMD 1:2011 is applicable with the the following additions.
4.1 Rated voltage (U )
r
Subclause 4.1 of IEC 62271-1:2007/AMD 1:2011 is applicable with the following addition:
The 1 100 kV and 1 200 kV voltage ratings do not apply to switches.
4.2 Rated insulation level
Subclause 4.2 of IEC 62271-1:2007/AMD 1:2011 is applicable.
4.3 Rated frequency (f )
r
Subclause 4.3 of IEC 62271-1:2007 is appl
...