IEC 62271-203:2011

IEC 62271-203 ®
Edition 2.0 2011-09
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
High-voltage switchgear and controlgear –
Part 203: Gas-insulated metal-enclosed switchgear for rated voltages above
52 kV
Appareillage à haute tension –
Partie 203: Appareillage sous enveloppe métallique à isolation gazeuse de
tensions assignées supérieures à 52 kV

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IEC 62271-203 ®
Edition 2.0 2011-09
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
High-voltage switchgear and controlgear –
Part 203: Gas-insulated metal-enclosed switchgear for rated voltages above
52 kV
Appareillage à haute tension –
Partie 203: Appareillage sous enveloppe métallique à isolation gazeuse de
tensions assignées supérieures à 52 kV

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX XC
ICS 29.130.10 ISBN 978-2-88912-664-4

– 2 – 62271-203  IEC:2011
CONTENTS
FOREWORD . 6
1 General . 8
1.1 Scope . 8
1.2 Normative references . 8
2 Normal and special service conditions . 9
2.1 Normal service conditions . 9
2.2 Special service conditions . 9
3 Terms and definitions . 10
4 Ratings . 12
4.1 Rated voltage (U ) . 13
r
4.2 Rated insulation level . 13
4.3 Rated frequency (f ) . 15
r
4.4 Rated normal current and temperature rise . 15
4.4.1 Rated normal current (I ) . 15
r
4.4.2 Temperature rise . 15
4.5 Rated short-time withstand current (I ) . 15
k
4.6 Rated peak withstand current (I ) . 15
p
4.7 Rated duration of short-circuit (t ) . 15
k
4.8 Rated supply voltage of closing and opening devices and of auxiliary and
control circuits (U ) . 15
a
4.9 Rated supply frequency of closing and opening devices and of auxiliary
circuits . 16
4.10 Rated pressure of compressed gas supply for controlled pressure systems . 16
4.11 Rated filling levels for insulation and/or operation . 16
5 Design and construction . 16
5.1 Requirements for liquids in switchgear and controlgear . 16
5.2 Requirements for gases in switchgear and controlgear . 16
5.3 Earthing of switchgear and controlgear . 16
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 . 18
5.11 Interlocking devices . 18
5.12 Position indication. 18
5.13 Degrees of protection by enclosures . 18
5.14 Creepage distances for outdoor insulators . 18
5.15 Gas and vacuum tightness . 19
5.15.1 Controlled pressure systems for gas . 19
5.15.2 Closed pressure systems for gas . 19
5.15.3 Sealed pressure systems . 19
5.16 Liquid tightness . 19
5.17 Fire hazard (flammability) . 19
5.18 Electromagnetic compatibility (EMC) . 19

62271-203  IEC:2011 – 3 –
5.19 X-Ray emission . 20
5.20 Corrosion . 20
5.101 Pressure coordination . 20
5.102 Internal fault . 21
5.103 Enclosures . 22
5.104 Partitions . 23
5.105 Pressure relief . 25
5.106 Noise . 26
5.107 Interfaces . 26
6 Type tests . 27
6.1 General . 27
6.1.1 Grouping of tests . 27
6.1.2 Information for identification of specimens . 28
6.1.3 Information to be included in type-tests reports . 29
6.2 Dielectric tests . 29
6.2.1 Ambient air conditions during tests . 29
6.2.2 Wet test procedure . 29
6.2.3 Conditions of switchgear and controlgear during dielectric tests. 29
6.2.4 Criteria to pass the test . 29
6.2.5 Application of the test voltage and test conditions . 29
6.2.6 Tests of switchgear and controlgear of U ≤ 245 kV . 30
r
6.2.7 Tests of switchgear and controlgear of rated voltage U >245 kV . 30
r
6.2.8 Artificial pollution tests for outdoor insulators . 31
6.2.9 Partial discharge tests . 31
6.2.10 Dielectric tests on auxiliary and control circuits . 32
6.2.11 Voltage test as condition check . 32
6.3 Radio interference voltage (r.i.v.) test . 32
6.4 Measurement of the resistance of circuits . 32
6.4.1 Main circuit . 32
6.4.2 Auxiliary circuits . 32
6.5 Temperature-rise tests. 32
6.5.1 Conditions of the switchgear and controlgear to be tested . 32
6.5.2 Arrangement of the equipment . 32
6.5.3 Measurement of the temperature and the temperature rise . 33
6.5.4 Ambient air temperature . 33
6.5.5 Temperature-rise test of the auxiliary and control equipment . 33
6.5.6 Interpretation of the temperature-rise tests . 33
6.6 Short-time withstand current and peak withstand current tests. 33
6.6.1 Arrangement of the switchgear and controlgear and of the test circuit . 33
6.6.2 Test current and duration . 33
6.6.3 Behaviour of switchgear and controlgear during test . 33
6.6.4 Conditions of switchgear and controlgear after test. 34
6.7 Verification of the protection . 34
6.7.1 Verification of the IP coding . 34
6.7.2 Verification of the IK coding . 34
6.8 Tightness tests . 34
6.8.1 Controlled pressure systems for gas . 34
6.8.2 Closed pressure systems for gas . 34
6.8.3 Sealed pressure systems . 35

– 4 – 62271-203  IEC:2011
6.8.4 Liquid tightness tests . 35
6.9 Electromagnetic compatibility tests (EMC) . 35
6.10 Additional tests on auxiliary and control circuits . 35
6.11 X-radiation test procedure for vacuum interrupters . 35
6.101 Verification of making and breaking capacities . 35
6.102 Mechanical and environmental tests. 35
6.103 Proof tests for enclosures . 36
6.104 Pressure test on partitions . 37
6.105 Test under conditions of arcing due to an internal fault . 37
6.106 Insulator tests . 38
6.107 Corrosion test on earthing connections . 38
6.108 Corrosion tests on enclosures . 39
7 Routine tests . 39
7.1 Dielectric test on the main circuit . 39
7.1.101 Power-frequency voltage tests on the main circuit . 40
7.1.102 Partial discharge measurement . 40
7.2 Tests on auxiliary and control circuits . 40
7.3 Measurement of the resistance of the main circuit . 40
7.4 Tightness test . 40
7.5 Design and visual checks. 40
7.101 Pressure tests of enclosures . 40
7.102 Mechanical operation tests . 41
7.103 Tests on auxiliary circuits, equipment and interlocks in the control mechanism . 41
7.104 Pressure test on partitions . 41
8 Guide to the selection of switchgear and controlgear . 41
8.1 Selection of rated values . 41
8.2 Continuous or temporary overload due to changed service conditions . 41
9 Information to be given with enquiries, tenders and orders . 42
9.1 Information with enquiries and orders . 42
9.2 Information with tenders . 42
10 Transport, storage, installation, operation and maintenance . 42
10.1 Conditions during transport, storage and installation . 42
10.2 Installation . 42
10.3 Operation . 47
10.4 Maintenance . 48
11 Safety . 48
12 Influence of the product on the environment . 48
Annex A (normative) Test procedure for dielectric test on three-phase encapsulated
GIS, range II . 49
Annex B (normative) Methods for testing gas-insulated metal-enclosed switchgear
under conditions of arcing due to an internal fault . 50
Annex C (informative) Technical and practical considerations of site testing . 53
Annex D (informative) Calculation of pressure rise due to an internal fault . 58
Annex E (informative) Information to be given with enquiries, tenders and orders . 59
Annex F (informative) Service continuity . 65
Annex G (informative) Insulation levels for GIS with rated voltages higher than 800 kV . 74
Annex H (informative) List of notes concerning certain countries . 75

62271-203  IEC:2011 – 5 –
Bibliography . 76

Figure 1 – Pressure coordination . 20
Figure 2 – Example of arrangement of enclosures and gas compartments . 25
Figure F.1 – Impact due to the removal of common partition between busbar-
disconnector . 66
Figure F.2 – Impact of GIS partitioning on service continuity . 67
Figure F.3 – Single line diagram with gas partitioning scheme . 67
Figure F.4 – Localisation and isolation . 69
Figure F.5 – Removal of busbar disconnector in SECTION-1 . 69
Figure F.6 – Removal of busbar disconnector in SECTION-3 . 70
Figure F.7 – Extension . 70
Figure F.8 – On-site dielectric test . 71

Table 1 – Reference table of service conditions relevant to GIS . 10
Table 2 – Rated insulation levels for rated voltages for equipment of range I. 14
Table 3 – Rated insulation levels for rated voltages for equipment of range II. 14
Table 4 – Performance criteria . 22
Table 5 – Example of grouping of type tests . 28
Table 6 – Test voltage for measuring PD intensity . 31
Table 7 – On site test voltages . 45
Table A.1 – Switching impulse test conditions above 245 kV . 49
Table E.1 – Normal and special service conditions . 59
Table E.2 – Ratings . 60
Table E.3 – Design and construction . 61
Table E.4 – Bus ducts . 62
Table E.5 – Bushing . 62
Table E.6 – Cable connection . 63
Table E.7 – Transformer connection . 63
Table E.8 – Current transformer . 63
Table E.9 – Inductive voltage transformer . 63
Table E.10 – Documentation for enquiries and tenders . 64
Table F.1 – Example for service continuity requirements . 72
Table G.1 – Insulation levels used for GIS with rated voltages higher than 800 kV in
different countries . 74

– 6 – 62271-203  IEC:2011
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
HIGH-VOLTAGE SWITCHGEAR AND CONTROLGEAR –

Part 203: Gas-insulated metal-enclosed switchgear
for rated voltages above 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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2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
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3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
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4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
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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 62271-203 has been prepared by subcommittee 17C: High-voltage
switchgear and controlgear assemblies, of IEC technical committee 17: Switchgear and
controlgear.
This second edition of IEC 62271-203 cancels and replaces the first edition of IEC 62271-203,
published in 2003, and constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
• adopting the structure and the content to IEC 62271-1,
• harmonisation with IEEE C37.122,
• addition of the new Annex F and the new Annex G.

62271-203  IEC:2011 – 7 –
The text of this standard is based on the following documents:
FDIS Report on voting
17C/512/FDIS 17C/524/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.
The reader's attention is drawn to the fact that Annex H lists all of the 'in-some-country' clauses
on differing practices of a less permanent nature relating to the subject of this standard.
This International Standard should be read in conjunction with IEC 62271-1:2007, to which it
refers and which is applicable unless otherwise specified. In order to simplify the indication of
corresponding requirements, the same numbering of clauses and subclauses is used as in
IEC 62271-1. Amendments to these clauses and subclauses are given under the same
numbering, whilst additional subclauses, are numbered from 101.
A list of all the parts of IEC 62271 series can be found under the general title High-voltage
switchgear and controlgear, 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 – 62271-203  IEC:2011
HIGH-VOLTAGE SWITCHGEAR AND CONTROLGEAR –

Part 203: Gas-insulated metal-enclosed switchgear
for rated voltages above 52 kV

1 General
1.1 Scope
This part of IEC 62271 specifies requirements for gas-insulated metal-enclosed switchgear in
which the insulation is obtained, at least partly, by an insulating gas other than air at
atmospheric pressure, for alternating current of rated voltages above 52 kV, for indoor and
outdoor installation, and for service frequencies up to and including 60 Hz.
For the purpose of this standard, the terms “GIS” and “switchgear” are used for “gas-insulated
metal-enclosed switchgear”.
The gas-insulated metal-enclosed switchgear covered by this standard consists of individual
components intended to be directly connected together and able to operate only in this manner.
This standard completes and amends, if necessary, the various relevant standards applying to
the individual components constituting GIS.
1.2 Normative references
The following referenced documents are indispensable for the application of this document.
For dated references, only the edition cited applies. For undated references, the latest edition
of the referenced document (including any amendments) applies.
IEC 60044-1:1996, Instrument transformers – Part 1: Current transformers
IEC 60044-2:1997, Instrument transformers – Part 2: Inductive voltage transformers
IEC 60068-2-11, Basic environmental testing procedures – Part 2-11: Tests – Test Ka: Salt
mist
IEC 60137:2008, Insulating bushings for alternating voltages above 1 000 V
IEC 60141-1, Tests on oil-filled and gas-pressure cables and their accessories – Part 1: Oil-
filled, paper-insulated, metal-sheathed cables and accessories for alternating voltages up to
and including 400 kV
IEC 60270, High-voltage test techniques – Partial discharge measurements
IEC 60376, Specification of technical grade sulfur hexafluoride (SF ) for use in electrical
equipment
IEC 60480, Guidelines for the checking and treatment of sulfur hexafluoride (SF ) taken from
electrical equipment and specification for its re-use
IEC 60840, Power cables with extruded insulation and their accessories for rated voltages
above 30 kV (U = 36 kV) up to 150 kV (U = 170 kV) – Test methods and requirements
m m
62271-203  IEC:2011 – 9 –
IEC/TR 61639:1996, Direct connection between power transformers and gas-insulated metal-
enclosed switchgear for rated voltages of 72,5 kV and above
IEC 62067, Power cables with extruded insulation and their accessories for rated voltages
above 150 kV (U = 170 kV) up to 500 kV (U = 550 kV) – Test methods and requirements
m m
IEC 62271-1:2007, High-voltage switchgear and controlgear – Part 1: Common specifications
IEC 62271-100:2008, High-voltage switchgear and controlgear – Part 100: Alternating-current
circuit-breakers
IEC 62271-102:2001, High-voltage switchgear and controlgear – Part 102: Alternating current
disconnectors and earthing switches
IEC 62271-209:2007, High-voltage switchgear and controlgear – Part 209: Cable connections
for gas-insulated metal-enclosed switchgear for rated voltages above 52 kV – Fluid-filled and
extruded insulation cables – Fluid-filled and dry-type cable-terminations
IEC/TR 62271-303, High-voltage switchgear and controlgear – Part 303: Use and handling of
sulphur hexafluoride (SF )
ISO 3231, Paints and varnishes – Determination of resistance to humid atmospheres
containing sulfur dioxide
2 Normal and special service conditions
Clause 2 of IEC 62271-1 is applicable with the following additions:
At any altitude the dielectric characteristics of the internal insulation are identical with those
measured at sea-level. For this internal insulation, therefore, no specific requirements
concerning the altitude are applicable.
Some items of a GIS such as pressure relief devices and pressure and density monitoring
devices may be affected by altitude. The manufacturer shall take appropriate measures if
necessary.
2.1 Normal service conditions
Subclause 2.1 of IEC 62271-1 is applicable, taking into account Table 1 of this standard.
2.2 Special service conditions
Subclause 2.2 of IEC 62271-1 is applicable, taking into account Table 1 of this standard.
In the cases where higher than (>) is used in the table the values shall be specified by the user
as described in IEC 62271-1.
– 10 – 62271-203  IEC:2011
Table 1 – Reference table of service conditions relevant to GIS
Normal Special
Item
Indoor Outdoor Indoor Outdoor
Ambient air temperature:
–5 or –25 –25 or –40 –25 –50
Minimum (°C)
+40 +40 +50 +50
Maximum (°C)
Solar radiation (W/m ) Not applicable 1 000 Not applicable >1 000
Altitude (m) 1 000 1 000 >1 000 >1 000
a
Site pollution severity Not applicable c c, d or e d or e
Ice coating (mm) Not applicable 1, 10 or 20 Not applicable >20
Wind (m/s) Not applicable 34 Not applicable >34
Humidity (%) 95 100 98 100
Condensation or precipitation Occasional Yes Yes Yes
Vibration class Not applicable Not applicable IEC 62271-207 IEC 62271-207
IEC/TR 62271- IEC/TR 62271-
300 300
NOTE The user’s specification may use any combination of normal or special service conditions above.
a
Site pollution severity c, d or e according to IEC/TS 60815-1:2008, 8.3.
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 62271-1, as well as
the following, apply.
3.101
metal-enclosed switchgear and controlgear
switchgear and controlgear assemblies with an external metal enclosure intended to be
earthed, and complete except for external connections
[IEC 60050-441:1984, 441-12-04]
3.102
gas-insulated metal-enclosed switchgear
metal-enclosed switchgear in which the insulation is obtained, at least partly, by an insulating
gas other than air at atmospheric pressure
[IEC 60050-441:1984, 441-12-05]
NOTE 1 This term generally applies to high-voltage switchgear and controlgear.
NOTE 2 Three-phase enclosed gas-insulated switchgear applies to switchgear with the three phases enclosed in
a common enclosure.
NOTE 3 Single-phase enclosed gas-insulated switchgear applies to switchgear with each phase enclosed in a
single independent enclosure.
3.103
gas-insulated switchgear enclosure
part of gas-insulated metal-enclosed switchgear retaining the insulating gas under the pre-
scribed conditions necessary to maintain safely the highest insulation level, protecting the
equipment against external influences and providing a high degree of protection to personnel
NOTE The enclosure can be single-phase or three-phase.

62271-203  IEC:2011 – 11 –
3.104
removable link
part of the conductor which can easily be removed in order to isolate two parts of the GIS from
each other
3.105
compartment
part of gas-insulated metal-enclosed switchgear, totally enclosed except for openings
necessary for interconnection and control
NOTE A compartment may be designated by the main component contained therein, e.g. circuit-breaker
compartment, busbar compartment.
3.106
component
essential part of the main or earthing circuits of gas-insulated metal-enclosed switchgear which
serves a specific function (for example circuit-breaker, disconnector, switch, fuse, instrument
transformer, bushing, busbar, etc.)
3.107
support insulator
internal insulator supporting one or more conductors
3.108
partition
support insulator of gas-insulated metal-enclosed switchgear separating one compartment from
other compartments
3.109
bushing
device that enables one or several conductors to pass through a partition such as a wall or a
tank, and insulate the conductors from it
NOTE The means of attachment (flange or fixing device) to the partition form part of the bushing.
[IEC 60050-471:2007, 471-02-01, modified]
3.110
main circuit
all the conductive parts of gas-insulated metal-enclosed switchgear included in a circuit which
is intended to transmit electrical energy
[IEC 60050-441:1984, 441-13-02, modified]
3.111
auxiliary circuit
all the conductive parts of gas-insulated metal-enclosed switchgear included in a circuit (other
than the main circuit) intended to control, measure, signal and regulate
NOTE The auxiliary circuits of gas-insulated metal-enclosed switchgear include the control and auxiliary circuits of
the switching devices.
3.112
design temperature of enclosures
maximum temperature that the enclosures can reach under specified maximum service
conditions
3.113
design pressure of enclosures
relative pressure used to determine the design of the enclosure

– 12 – 62271-203  IEC:2011
NOTE 1 It is at least equal to the maximum pressure in the enclosure at the highest temperature that the gas used
for insulation can reach under specified maximum service conditions.
NOTE 2 The transient pressure occurring during and after a breaking operation (e.g. circuit-breaker) is not to be
considered in the determination of the design pressure.
3.114
design pressure of partitions
relative pressure across the partition
NOTE 1 It is at least equal to the maximum relative pressure across the partition during maintenance activities.
NOTE 2 The transient pressure occurring during and after a breaking operation (e.g. circuit-breaker) is not to be
considered in the determination of the design pressure.
3.115
operating pressure of pressure relief device
relative pressure chosen for the opening operation of pressure relief devices
3.116
routine test pressure of enclosures and partitions
relative pressure to which all enclosures and partitions are subjected after manufacturing
3.117
type test pressure of enclosures and partitions
relative pressure to which all enclosures and partitions are subjected for type test
3.118
fragmentation
damage to enclosure due to pressure rise with projection of solid material
NOTE The term “no fragmentation of the enclosure” is interpreted as follows:
– no explosion of the compartment;
– no solid parts flying off from the compartment.
Exceptions are:
– parts of the pressure relief device, if their ejection is directed;
– glowing particles and molten material resulting from burn-through of the enclosure.
3.119
disruptive discharge
phenomena associated with the failure of insulation under electric stress, in which the
discharge completely bridges the insulation under test, reducing the voltage between the
electrodes to zero or almost zero
3.120
service period
time until a maintenance, including opening of the gas compartments, is required
3.121
transport unit
part of gas-insulated metal-enclosed switchgear suitable for shipment without being dismantled
4 Ratings
Clause 4 of IEC 62271-1 is applicable with the following modifications:

62271-203  IEC:2011 – 13 –
e) rated short-time withstand current (I ) (for main and earthing circuits);
k
f) rated peak withstand current (I ) (for main and earthing circuits);
p
and with the following addition:
l) rated values of the components forming part of gas-insulated metal-enclosed switchgear,
including their operating devices and auxiliary equipment.
4.1 Rated voltage (U )
r
Subclause 4.1 of IEC 62271-1 is applicable with the following addition:
NOTE Components forming part of the GIS may have individual values of rated voltage for equipment in
accordance with the relevant standards.
4.2 Rated insulation level
Subclause 4.2 of IEC 62271-1 is applicable with the following addition:
Tables 1 and 2 in Subclause 4.2 of IEC 62271-1 are replaced by Tables 2 and 3 below.
For rated voltages above 800 kV, see Annex G.
The GIS comprises components having a definite insulation level. Although internal faults can
largely be avoided by the choice of a suitable insulation level, measures to limit external
overvoltages (e.g. surge arresters,) should be considered.
NOTE 1 According to CIGRE studies the natural ratio between the withstand voltages under standard tests, for
SF gas insulation is U / U = 0,45 and U / U = 0,75. The values U shown in Table 3 are calculated with these
6 d p s p d
factors.
NOTE 2 Regarding the external parts of bushings (if any), refer to IEC 60137.
NOTE 3 The waveforms are standardized lightning impulse and switching impulse shapes, pending the results of
studies on the ability of this equipment to withstand other types of impulses.
NOTE 4 The choice between alternative insulation levels for a particular rated voltage for equipment should be
based on insulation coordination studies, taking into account also the self-generated transie
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