IEC 62271-204:2022

IEC 62271-204 EXV ®
Edition 2.0 2022-09
EXTENDED VERSION
INTERNATIONAL
STANDARD
colour
inside
This extended version of IEC 62271-204:2022 includes the content of the references made to
IEC 62271-1:2017+AMD1:2021 CSV and IEC 62271-203:2022
High-voltage switchgear and controlgear –
Part 204: Rigid gas-insulated transmission lines for rated voltage above 52 kV
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form
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IEC 62271-204 EXV ®
Edition 2.0 2022-09
EXTENDED VERSION
INTERNATIONAL
STANDARD
colour
inside
This extended version of IEC 62271-204:2022 includes the content of the references made to
IEC 62271-1:2017+AMD1:2021 CSV and IEC 62271-203:2022

High-voltage switchgear and controlgear –
Part 204: Rigid gas-insulated transmission lines for rated voltage above 52 kV
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 29.130.10 ISBN 978-2-8322-5677-0
IEC 62271-1:2017/ISH1:2021 – 1 –
© IEC 2021
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
IEC 62271-1
Edition 2.0  2017-07
HIGH-VOLTAGE SWITCHGEAR AND CONTROLGEAR –

Part 1: Common specifications for alternating
current switchgear and controlgear

INT ERPRET AT ION SHEET 1
This interpretation sheet has been prepared by IEC technical committee 17: High-voltage
switchgear and controlgear.
The text of this interpretation sheet is based on the following documents:
DISH Report on voting
17/1090/DISH 17/1095/RVDISH
Full information on the voting for the approval of this interpretation sheet can be found in the
report on voting indicated in the above table.

___________
Interpretation of 4.2.2 of IEC 62271-1:2017 regarding the altitude correction factor
Subclause 4.2.2 of IEC 62271-1:2017 contains two references for calculation of the required
insulation withstand level at altitudes higher than 1 000 m, IEC 60071-2:1996 and
IEC TR 62271-306. The two references are in conflict, as the altitude correction factor
according to IEC 60071-2:1996 starts at sea level and that of IEC TR 62271-306 starts at an
altitude of 1 000 m. This results in different altitude correction factors.
As already stated in 5.3 of IEC 62271-1:2017, the rated insulation levels refer to normal
service conditions. Altitudes up to 1 000 m above sea level are covered and need no altitude
correction.
For altitudes higher than 1 000 m the equation provided in 4.5.1.1 b) of
IEC TR 62271-306:2012 and in H.3.4 of IEC 60071-2:2018 shall be used, i.e.
H−1 000
m( )
8 150
k =e
alt
ICS 29.130.10; 29.130.99
IEC 62271-1:2017-07/ISH1:2021-05(en-fr)

– 2 – IEC 62271-1:2017/ISH1:2021
© IEC 2021
where
k is the altitude correction factor;
alt
H is the altitude in m above sea level;
m is an exponent.
Conservative values for the exponent m are provided in Table 4 of IEC TR 62271-306:2012.
For further details about the exponent m, see H.4 of IEC 60071-2:2018.

– 2 – IEC 62271-204:2022 EXV © IEC 2022
CONTENTS
FOREWORD . 10
1 Scope . 12
2 Normative references . 12
3 Terms and definitions . 15
3.1 General terms and definitions . 15
3.2 Assemblies of switchgear and controlgear . 18
3.3 Parts of assemblies . 18
3.4 Switching devices . 19
3.5 Parts of switchgear and controlgear . 19
3.6 Operational characteristics of switchgear and controlgear . 23
3.7 Characteristic quantities . 26
3.8 Index of definitions . 27
4 Normal and special service conditions . 31
4.1 Normal service conditions . 31
4.1.1 General . 31
4.1.2 Indoor switchgear and controlgear . 31
4.1.3 Outdoor switchgear and controlgear . 31
4.2 Special service conditions . 32
4.2.1 General . 32
4.2.2 Altitude . 32
4.2.3 Exposure to pollution . 32
4.2.4 Temperature and humidity . 33
4.2.5 Exposure to abnormal vibrations, shock or tilting . 33
4.2.6 Wind speed . 33
4.2.7 Other parameters . 33
4.101 Installation in open air. 33
4.102 Buried installation . 33
4.103 Installation in tunnel, shaft or similar situation . 34
5 Ratings . 34
5.1 General . 34
5.2 Rated voltage (U ) . 34
r
5.2.1 General . 34
5.2.2 Range I for rated voltages of 245 kV and below . 35
5.2.3 Range II for rated voltages above 245 kV . 35
5.3 Rated insulation level (U , U , U ) . 35
d p s
5.4 Rated frequency (f ) . 39
r
5.5 Rated continuous current (I ) . 39
r
5.6 Rated short-time withstand current (I ) . 40
k
5.7 Rated peak withstand current (I ) . 40
p
5.8 Rated duration of short-circuit (t ) . 40
k
5.9 Rated supply voltage of auxiliary and control circuits (U ) . 41
a
5.9.1 General . 41
5.9.2 Rated supply voltage (U ). 41
a
5.10 Rated supply frequency of auxiliary and control circuits . 41
5.11 Rated pressure of compressed gas supply for controlled pressure systems . 41
6 Design and construction . 42
6.1 Requirements for liquids in GIL . 42
6.2 Requirements for gases in GIL . 42
6.3 Earthing . 42
6.3.101 Earthing of the main circuits . 43
6.3.102 Earthing of the enclosure . 43
6.4 Auxiliary and control equipment . 43
6.4.1 General . 43
6.4.2 Protection against electric shock . 44
6.4.3 Components installed in enclosures . 45
6.5 Dependent power operation . 47
6.6 Stored energy operation. 47
6.7 Independent manual or power operation (independent unlatched operation) . 48
6.8 Manually operated actuators . 48
6.9 Operation of releases . 48
6.10 Pressure/level indication . 48
6.10.1 Gas pressure. 48
6.10.2 Liquid level . 48
6.11 Nameplates . 48
6.11.1 General . 48
6.11.2 Application . 49
6.12 Locking devices . 49
6.13 Position indication . 49
6.14 Degree of protection provided by enclosures . 49
6.14.1 General . 49
6.14.2 Protection of persons against access to hazardous parts and protection of
the equipment against ingress of solid foreign objects (IP coding) . 49
6.14.3 Protection against ingress of water (IP coding) . 50
6.14.4 Protection against mechanical impact under normal service conditions
(IK coding) . 50
6.15 Creepage distances for outdoor insulators . 50
6.16 Gas and vacuum tightness . 50
6.16.1 General . 50
6.16.2 Controlled pressure systems for gas .
...

IEC 62271-204 ®
Edition 2.0 2022-05
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
High-voltage switchgear and controlgear –
Part 204: Rigid gas-insulated transmission lines for rated voltage above 52 kV

Appareillage à haute tension –
Partie 204: Lignes de transport rigides à isolation gazeuse de tension assignée
supérieure à 52 kV
All rights reserved. Unless otherwise specified, 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
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About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.

About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigendum or an amendment might have been published.

IEC publications search - webstore.iec.ch/advsearchform IEC Products & Services Portal - products.iec.ch
The advanced search enables to find IEC publications by a Discover our powerful search engine and read freely all the
variety of criteria (reference number, text, technical publications previews. With a subscription you will always
committee, …). It also gives information on projects, replaced have access to up to date content tailored to your needs.
and withdrawn publications.
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containing more than 22 300 terminological entries in English
details all new publications released. Available online and
and French, with equivalent terms in 19 additional languages.
once a month by email.
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(IEV) online.
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IEC 62271-204 ®
Edition 2.0 2022-05
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
High-voltage switchgear and controlgear –
Part 204: Rigid gas-insulated transmission lines for rated voltage above 52 kV
Appareillage à haute tension –
Partie 204: Lignes de transport rigides à isolation gazeuse de tension assignée
supérieure à 52 kV
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.130.10 ISBN 978-2-8322-3804-2
– 2 – IEC 62271-204:2022 © IEC 2022
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 6
4 Normal and special service conditions . 8
5 Ratings . 9
6 Design and construction . 10
7 Type tests . 21
8 Routine tests . 28
9 Guide to the selection of GIL (informative) . 29
10 Information to be given with enquiries, tenders and orders (informative) . 30
11 Transport, storage, installation, operating instructions and maintenance. 32
12 Safety . 38
13 Influence of the product on the environment . 39
Annex A (informative) Estimation of continuous current . 40
Annex B (informative) Earthing . 45
Annex C (informative) Long-term testing of buried installations . 49
Annex D (normative) Requirements for welds on pressurized parts . 51
Bibliography . 53

Figure B.1 – Example of earthing system together with active anti-corrosion system in
the case of solid bonding of the enclosure at both ends . 48

Table 1 – Second characteristic numeral of IP coding . 14
Table D.1 – Quantity of NDTs . 51
Table D.2 – Acceptance criteria of imperfections . 52

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
HIGH-VOLTAGE SWITCHGEAR AND CONTROLGEAR –

Part 204: Rigid gas-insulated transmission lines
for rated voltage 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 this end and
in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports,
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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.
IEC 62271-204 has been prepared by subcommittee 17C: Assemblies, of IEC technical
committee 17: High-voltage switchgear and controlgear. It is an International Standard.
This second edition cancels and replaces the first edition published in 2011. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) update to be in line with IEC 62271-1:2017 and alignment of the voltage ratings and the test
voltages.
b) addition of new information for welds on pressurized parts and gas tightness.

– 4 – IEC 62271-204:2022 © IEC 2022
The text of this document is based on the following documents:
Draft Report on voting
17C/840/FDIS 17C/846/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/standardsdev/publications.
This document is to be read in conjunction with IEC 62271-1:2017 and IEC 62271-203:2022, to
which it refers and which are 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 62271-1:2017 and IEC 62271-203:2022. Amendments to these clauses and
subclauses are given under the same numbering, whilst additional subclauses are numbered
from 101.
A list of all parts of the 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 document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
HIGH-VOLTAGE SWITCHGEAR AND CONTROLGEAR –

Part 204: Rigid gas-insulated
...