SIST EN IEC 61936-1:2021

Power installations exceeding 1 kV AC and 1,5 kV DC - Part 1: AC

This part of IEC 61936 provides requirements for the design and the erection of electrical power
installations in systems with nominal voltages exceeding 1 kV AC and nominal frequency up to
and including 60 Hz, so as to provide safety and proper functioning for the use intended.
For the purpose of interpreting this document, an electrical power installation is considered to
be one of the following:
a) substation, including substation for railway power supply;
b) electrical power installations on mast, pole and tower, switchgear and/or transformers
located outside a closed electrical operating area;
c) one (or more) power station(s) located on a single site, the electrical power installation
includes generators and transformers with all associated switchgear and all electrical
auxiliary systems. Connections between generating stations located on different sites are
excluded;
d) the electrical system of a factory, industrial plant or other industrial, agricultural, commercial
or public premises;
e) electrical power installations on offshore facilities for the purpose of generation,
transmission, distribution and/or storage of electricity;
f) transition towers/poles (between overhead lines and underground lines).
The electrical power installation includes, among others, the following equipment:
– rotating electrical machines;
– switchgear;
– transformers and reactors;
– converters;
– cables;
– wiring systems;
– batteries;
– capacitors;
– earthing systems;
– buildings and fences which are part of a closed electrical operating area;
– associated protection, control and auxiliary systems;
– large air core reactor.
NOTE 1 In general, equipment standards take precedence over the requirements of this document.
This document does not apply to the design and erection of any of the following:
– overhead and underground lines between separate electrical power installations;
– electrified railway tracks and rolling stock;
– mining equipment and installations;
fluorescent lamp installations;
– installations on ships according to IEC 60092 (all parts) and offshore units according to
IEC 61892 (all parts), which are used in the offshore petroleum industry for drilling,
processing and storage purposes;
– electrostatic equipment (e.g. electrostatic precipitators, spray-painting units);
– test sites;
– medical equipment, e.g. medical X-ray equipment.
This document does not apply to the design of prefabricated, type-tested switchgear and high
voltage/low voltage prefabricated substation, for which separate IEC standards exist.
NOTE 2 The scope of this document does not include the requirements for carrying out live working on electrical
power installations.
NOTE 3 The scope of this document considers safety requirements for HV installations and the influences of HV
installations on LV installations. For electrical installations up to 1 kV, IEC 60364 (all parts) applies.

Starkstromanlagen mit Nennwechselspannungen über 1 kV AC und 1,5 kV DC - Teil 1: Wechselstrom

Installations électriques de puissance de tension supérieure à 1 kV en courant alternatif et 1,5 kV en courant continu - Partie 1: Courant alternatif

L’IEC 61936-1:2021 fournit des exigences relatives à la conception et au montage des installations électriques dans des systèmes dont les tensions nominales sont supérieures à 1 kV en courant alternatif et la fréquence nominale inférieure ou égale à 60 Hz, afin d'assurer la sécurité et le fonctionnement correct pour l'utilisation prévue.
L'installation électrique comprend notamment les matériels suivants:

   
• machines électriques tournantes;

   
• appareillage;

   
• transformateurs et réactances;

   
• convertisseurs;

   
• câbles;

   
• canalisations électriques;

   
• batteries;

   
• condensateurs;

   
• installations de mise à la terre;

   
• bâtiments et clôtures qui font partie d'une installation électrique fermée;

   
• systèmes associés de protection, de commande et auxiliaires;

   
• réactance élevée à noyau d’air.

Le présent document ne s'applique pas à la conception des appareillages préfabriqués soumis à un essai de type et des postes préfabriqués à haute tension/basse tension, pour lesquels des normes IEC spécifiques existent.
Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:

   
1. l’introduction a été remaniée pour refléter la réalité au moment de la rédaction du présent document;

   
2. le domaine d’application a été amélioré pour clarifier l’application du présent document;

   
3. les termes et définitions manquants et obsolètes ont été mis à jour, et les termes existants ont été améliorés;

   
4. le Tableau 1 a été mis à jour pour tenir compte des situations qui nécessitent des accords entre le fournisseur et l’utilisateur;

   
5. les exigences en matière de compatibilité électromagnétique ont été clarifiées;

   
6. la formulation de l’Article 5) relatif à la coordination de l’isolement a été améliorée et la coordination de son contenu technique avec les dernières versions des normes de coordination de l’isolement a été mise à jour;

   
7. la formulation concernant les matériels électriques a été améliorée et clarifiée;

   
8. le paragraphe relatif aux fusibles a été amélioré et reformulé;

   
9. des exigences en matière d’étiquetage ont été introduites lorsque des sources multiples doivent être déconnectées;

   
10. les exigences manquantes pour les postes sous enveloppe métallique (PSEM) ont été réintroduites;

   
11. amélioration du paragraphe relatif à la ventilation

Elektroenergetski postroji za izmenične napetosti nad 1 kV in enosmerne napetosti nad 1,5 kV - 1. del: Izmenična napetost

General Information

• Status: Published
• Publication Date: 04-Oct-2021
• ICS: 29.020 - Electrical engineering in general
• ICS: 29.080.01 - Electrical insulation in general
• ICS: 29.240.01 - Power transmission and distribution networks in general
• Technical Committee: IVNI - High voltage power installations
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 01-Sep-2021
• Due Date: 06-Nov-2021
• Completion Date: 05-Oct-2021
• Directive: TP170 - Pravilnik o zaščiti nizkonapetostnih omrežij in pripadajočih transformatorskih postaj
• Directive: TP225 - Pravilnik o elektroenergetskih postrojih izmenične napetosti nad 1 kV
• Ref Project: EN IEC 61936-1:2021 - Power installations exceeding 1 kV AC and 1,5 kV DC - Part 1: AC

Relations

• Revised: SIST EN 61936-1:2011/A1:2014 - Power installations exceeding 1 kV a.c. - Part 1: Common rules
• Effective Date: 28-Apr-2020
• Revised: SIST EN 61936-1:2011/AC:2013 - Power installations exceeding 1 kV a.c. - Part 1: Common rules
• Effective Date: 28-Apr-2020
• Revised: SIST EN 61936-1:2011 - Power installations exceeding 1 kV a.c. - Part 1: Common rules (IEC 61936-1:2010, modified)
• Effective Date: 05-Feb-2019
• Replaces: SIST EN 61936-1:2011/AC:2012 - Power installations exceeding 1 kV a.c. -- Part 1: Common rules
• Effective Date: 31-Aug-2021
• Replaces: SIST EN 61936-1:2011/A1:2014 - Power installations exceeding 1 kV a.c. - Part 1: Common rules
• Effective Date: 31-Aug-2021
• Replaces: SIST EN 61936-1:2011/AC:2013 - Power installations exceeding 1 kV a.c. - Part 1: Common rules
• Effective Date: 31-Aug-2021
• Replaces: SIST EN 61936-1:2011 - Power installations exceeding 1 kV a.c. - Part 1: Common rules (IEC 61936-1:2010, modified)
• Effective Date: 31-Aug-2021
• Replaces: SIST EN 61936-1:2011/AC:2012 - Power installations exceeding 1 kV a.c. -- Part 1: Common rules
• Effective Date: 07-Jun-2022
• Replaces: SIST EN 61936-1:2011 - Power installations exceeding 1 kV a.c. - Part 1: Common rules (IEC 61936-1:2010, modified)
• Effective Date: 07-Jun-2022

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN IEC 61936-1:2021
01-november-2021
Nadomešča:
SIST EN 61936-1:2011
SIST EN 61936-1:2011/A1:2014
SIST EN 61936-1:2011/AC:2012
SIST EN 61936-1:2011/AC:2013
Elektroenergetski postroji za izmenične napetosti nad 1 kV in enosmerne
napetosti nad 1,5 kV - 1. del: Izmenična napetost
Power installations exceeding 1 kV AC and 1,5 kV DC - Part 1: AC
Ta slovenski standard je istoveten z: EN IEC 61936-1:2021
ICS:
29.240.01 Omrežja za prenos in Power transmission and
distribucijo električne energije distribution networks in
na splošno general
SIST EN IEC 61936-1:2021 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN IEC 61936-1:2021

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SIST EN IEC 61936-1:2021


EUROPEAN STANDARD EN IEC 61936-1

NORME EUROPÉENNE

EUROPÄISCHE NORM
August 2021
ICS 29.020; 29.080.01 Supersedes EN 61936-1:2010 and all of its amendments
and corrigenda (if any)
English Version
Power installations exceeding 1 kV AC and 1,5 kV DC - Part 1:
AC
(IEC 61936-1:2021)
Installations électriques de puissance de tension supérieure Starkstromanlagen mit Nennwechselspannungen über 1 kV
à 1 kV en courant alternatif et 1,5 kV en courant continu - AC und 1,5 kV DC - Teil 1: Wechselstrom
Partie 1: Courant alternatif (IEC 61936-1:2021)
(IEC 61936-1:2021)
This European Standard was approved by CENELEC on 2021-08-11. CENELEC members are bound to comply with the CEN/CENELEC
Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.
Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC
Management Centre or to any CENELEC member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the
same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the
Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.


European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2021 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
 Ref. No. EN IEC 61936-1:2021 E

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SIST EN IEC 61936-1:2021
EN IEC 61936-1:2021 (E)
European foreword
The text of document 99/311/FDIS, future edition 3 of IEC 61936-1, prepared by IEC/TC 99 “Insulation
co-ordination and system engineering of high voltage electrical power installations above 1,0 kV AC
and 1,5 kV DC” was submitted to the IEC-CENELEC parallel vote and approved by CENELEC as
EN IEC 61936-1:2021.
The following dates are fixed:
• latest date by which the document has to be implemented at national (dop) 2022–05–11
level by publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2024–08–11
document have to be withdrawn
This document supersedes EN 61936-1:2010 and all of its amendments and corrigenda (if any).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC shall not be held responsible for identifying any or all such patent rights.
Any feedback and questions on this document should be directed to the users’ national committee. A
complete listing of these bodies can be found on the CENELEC website.
Endorsement notice
The text of the International Standard IEC 61936-1:2021 was approved by CENELEC as a European
Standard without any modification.
In the official version, for Bibliography, the following notes have to be added for the standards
indicated:
IEC 60034-3 NOTE Harmonized as EN IEC 60034-3
IEC 60038 NOTE Harmonized as EN 60038
IEC 60068 (series) NOTE Harmonized as EN 60068 (series)
IEC 60076-13 NOTE Harmonized as EN 60076-13
IEC 60092 (series) NOTE Harmonized as EN 60092 (series)
IEC 60282-1 NOTE Harmonized as EN IEC 60282-1
IEC 60364-4-41 NOTE Harmonized as HD 60364-4-41
IEC 60364-7-729 NOTE Harmonized as HD 60364-7-729
IEC 60376 NOTE Harmonized as EN IEC 60376
IEC 60480 NOTE Harmonized as EN IEC 60480
IEC 60664-1 NOTE Harmonized as EN IEC 60664-1
IEC 60721 (series) NOTE Harmonized as EN 60721 (series)
IEC 60721-2-2 NOTE Harmonized as EN 60721-2-2
2

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SIST EN IEC 61936-1:2021
EN IEC 61936-1:2021 (E)
IEC 60721-2-3 NOTE Harmonized as EN 60721-2-3
IEC 60721-2-4 NOTE Harmonized as EN IEC 60721-2-4
IEC 60721-2-7 NOTE Harmonized as EN IEC 60721-2-7
IEC 60721-3-1 NOTE Harmonized as EN IEC 60721-3-1
IEC 60721-3-2 NOTE Harmonized as EN IEC 60721-3-2
IEC 60832 (series) NOTE Harmonized as EN 60832 (series)
IEC 60855-1 NOTE Harmonized as EN 60855-1
IEC 60865-1 NOTE Harmonized as EN 60865-1
IEC 60909 (series) NOTE Harmonized as EN 60909 (series)
IEC 61000 (series) NOTE Harmonized as EN IEC 61000 (series)
IEC 61039 NOTE Harmonized as EN 61039
IEC 61082-1 NOTE Harmonized as EN 61082-1
IEC 61243 (series) NOTE Harmonized as EN 61243 (series)
IEC 61355-1 NOTE Harmonized as EN 61355-1
IEC 61869 (series) NOTE Harmonized as EN IEC 61869 (series)
IEC 62271-4 NOTE Harmonized as EN 62271-4
IEC 62271-100 NOTE Harmonized as EN 62271-100
IEC 62271-102 NOTE Harmonized as EN IEC 62271-102
IEC 62271-103 NOTE Harmonized as EN 62271-103
IEC 62271-104 NOTE Harmonized as EN IEC 62271-104
IEC 62271-105 NOTE Harmonized as EN 62271-105
IEC 62271-206 NOTE Harmonized as EN 62271-206
IEC 62305 (series) NOTE Harmonized as EN 62305 (series)
IEC 81346 (series) NOTE Harmonized as EN IEC 81346 (series)
ISO 26800 NOTE Harmonized as EN ISO 26800
3

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SIST EN IEC 61936-1:2021
EN IEC 61936-1:2021 (E)
Annex ZA
(normative)

Normative references to international publications
with their corresponding European publications
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements 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.
NOTE 1 Where an International Publication has been modified by common modifications, indicated by (mod), the
relevant EN/HD applies.
NOTE 2 Up-to-date information on the latest versions of the European Standards listed in this annex is available
here: www.cenelec.eu.
Publication Year Title EN/HD Year
IEC 60034-1 - Rotating electrical machines - Part 1: - -
Rating and performance
IEC 60060-1 - High-voltage test techniques - Part 1: EN 60060-1 -
General definitions and test requirements
IEC 60071-1 2019 Insulation co-ordination - Part 1: EN IEC 60071-1 2019
Definitions, principles and rules
IEC 60071-2 - Insulation co-ordination – Part 2: EN IEC 60071-2 -
Application guidelines
IEC 60076 series Power transformers EN 60076 series
IEC 60079-0 - Explosive atmospheres - Part 0: EN IEC 60079-0 -
Equipment - General requirements
IEC 60079-10-1 - Explosive atmospheres - Part 10–1: EN IEC 60079-10-1 -
Classification of areas - Explosive gas
atmospheres
IEC 60079-10-2  Explosive atmospheres - Part 10–2: EN 60079-10-2
Classification of areas - Explosive dust
atmospheres
IEC 60255 series Measuring relays and protection equipment EN 60255 series
IEC 60331-1 - Tests for electric cables under fire EN IEC 60331-1 -
conditions - Circuit integrity - Part 1: Test
method for fire with shock at a temperature
of at least 830 °C for cables of rated
voltage up to and including 0,6/1,0 kV and
with an overall diameter exceeding 20 mm
IEC 60331-21 - Tests for electric cables under fire - -
conditions - Circuit integrity - Part 21:
Procedures and requirements - Cables of
rated voltage up to and including
0,6/1,0 kV
IEC 60332 series Tests on electric cables under fire EN 60332 series
conditions
4

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SIST EN IEC 61936-1:2021
EN IEC 61936-1:2021 (E)
IEC 60364 series Low-voltage electrical installations HD 60364 series
IEC 60479-1 2018 Effects of current on human beings and - -
livestock - Part 1: General aspects
IEC 60529 - Degrees of protection provided by - -
enclosures (IP Code)
IEC 60754 series Test on gases evolved during combustion EN 60754 series
of materials from cables
IEC 61034-1 - Measurement of smoke density of cables EN 61034-1 -
burning under defined conditions - Part 1:
Test apparatus
IEC 61219 - Live working - Earthing or earthing and EN 61219 -
short-circuiting equipment using lances as
a short-circuiting device - Lance earthing
IEC 61230 - Live working - Portable equipment for EN 61230 -
earthing or earthing and short-circuiting
IEC 62271-1 2017 High-voltage switchgear and controlgear - EN 62271-1 2017
Part 1: Common specifications for
alternating current switchgear and
controlgear
IEC 62271-200 - High-voltage switchgear and controlgear - EN IEC 62271-200 -
Part 200: AC metal-enclosed switchgear
and controlgear for rated voltages above
1 kV and up to and including 52 kV
IEC 62271-201 - High-voltage switchgear and controlgear - EN 62271-201 -
Part 201: AC solid-insulation enclosed
switchgear and controlgear for rated
voltages above 1 kV and up to and
including 52 kV
IEC 62271-202 - High-voltage switchgear and controlgear - EN 62271-202 -
Part 202: High-voltage/ low-voltage
prefabricated substation
IEC 62271-203 - High-voltage switchgear and controlgear - EN 62271-203 -
Part 203: Gas-insulated metal-enclosed
switchgear for rated voltages above 52 kV
IEC 62271-207 - High-voltage switchgear and controlgear - EN 62271-207 -
Part 207: Seismic qualification for gas-
insulated switchgear assemblies for rated
voltages above 52 kV
IEC 62305 series Protection against lightning EN 62305 series
IEC/TR 61000-5-2 - Electromagnetic compatibility (EMC) - Part - -
5: Installation and mitigation guidelines -
Section 2: Earthing and cabling
IEC/TR 62271-300 - High-voltage switchgear and controlgear - - -
Part 300: Seismic qualification of
alternating current circuit-breakers
IEC/TS 60815-1 - Selection and dimensioning of high-voltage - -
insulators intended for use in polluted
conditions - Part 1: Definitions, information
and general principles
5

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SIST EN IEC 61936-1:2021
EN IEC 61936-1:2021 (E)
IEC/TS 60815-2 - Selection and dimensioning of high-voltage - -
insulators intended for use in polluted
conditions - Part 2: Ceramic and glass
insulators for a.c. systems
IEC/TS 60815-3 - Selection and dimensioning of high-voltage - -
insulators intended for use in polluted
conditions - Part 3: Polymer insulators for
a.c. systems
IEC/TS 61463 - Bushings - Seismic qualification - -
IEC/IEEE 82079-1 - Preparation of information for use EN -
(instructions for use) of products - Part 1: IEC/IEEE 82079-1
Principles and general requirements


6

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SIST EN IEC 61936-1:2021
IEC 61936-1
®

Edition 3.0 2021-07
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Power installations exceeding 1 kV AC and 1,5 kV DC –
Part 1: AC
Installations électriques de puissance de tension supérieure à 1 kV en courant
alternatif et 1,5 kV en courant continu –
Partie 1: Courant alternatif
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.020; 29.080.01 ISBN 978-2-8322-9887-9
Warning! Make sure that you obtained this publication from an authorized distributor.
Attention! Veuillez vous assurer que vous avez obtenu cette publication via un distributeur agréé.
® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale

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SIST EN IEC 61936-1:2021
– 2 – IEC 61936-1:2021 © IEC 2021
CONTENTS
FOREWORD . 8
INTRODUCTION . 11
1 Scope . 12
2 Normative references . 13
3 Terms and definitions . 15
3.1 General definitions . 15
3.2 Definitions concerning electrical power installations . 17
3.3 Definitions concerning types of electrical power installations. 18
3.4 Definitions concerning safety measures against electric shock . 18
3.5 Definitions concerning clearances . 19
3.6 Definitions concerning control and protection . 21
3.7 Definitions concerning earthing . 21
4 Fundamental requirements . 25
4.1 General . 25
4.1.1 General requirements . 25
4.1.2 Agreements between supplier and user . 26
4.2 Electrical requirements . 28
4.2.1 Methods of neutral earthing . 28
4.2.2 Voltage classification . 28
4.2.3 Current in normal operation . 28
4.2.4 Short-circuit current . 28
4.2.5 Rated frequency . 29
4.2.6 Corona . 29
4.2.7 Electric and magnetic fields . 29
4.2.8 Overvoltages . 30
4.2.9 Harmonics . 30
4.2.10 Electromagnetic compatibility . 30
4.3 Mechanical requirements . 30
4.3.1 General . 30
4.3.2 Tension load . 31
4.3.3 Erection load . 31
4.3.4 Ice load . 31
4.3.5 Wind load . 31
4.3.6 Switching forces . 31
4.3.7 Short-circuit forces . 31
4.3.8 Loss of conductor tension . 31
4.3.9 Seismic loads . 31
4.3.10 Dimensioning of structures . 32
4.4 Climatic and environmental conditions . 32
4.4.1 General . 32
4.4.2 Normal conditions . 32
4.4.3 Special conditions . 34
4.5 Particular requirements . 35
4.5.1 Effects of small animals and micro-organisms. 35
4.5.2 Noise level . 35
4.5.3 Transport . 35

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SIST EN IEC 61936-1:2021
IEC 61936-1:2021 © IEC 2021 – 3 –
5 Insulation . 35
5.1 General . 35
5.2 Selection of insulation level. 36
5.2.1 General . 36
5.2.2 Consideration of methods of neutral earthing . 36
5.2.3 Consideration of rated withstand voltages . 36
5.3 Verification of withstand values . 36
5.4 Minimum clearances of live parts . 37
5.4.1 General . 37
5.4.2 Minimum clearances in voltage range I . 37
5.4.3 Minimum clearances in voltage range II . 37
5.5 Minimum clearances between parts under special conditions . 40
5.6 Tested connection zones . 40
6 Electrical equipment . 40
6.1 General requirements . 40
6.1.1 Electrical equipment safety . 40
6.1.2 User safety . 40
6.2 Specific requirements . 41
6.2.1 Switching devices . 41
6.2.2 Power transformers and reactors . 41
6.2.3 Prefabricated type-tested switchgear . 42
6.2.4 Instrument transformers . 42
6.2.5 Surge arresters . 43
6.2.6 Capacitors . 43
6.2.7 Line traps . 44
6.2.8 Insulators . 44
6.2.9 Insulated cables . 44
6.2.10 Conductors and accessories . 47
6.2.11 Rotating electrical machines . 47
6.2.12 Generating units . 48
6.2.13 Generating unit main connections . 48
6.2.14 Static converters . 48
6.2.15 Fuses . 49
6.2.16 Electrical and mechanical interlocking . 49
7 Electrical power installations . 49
7.1 General . 49
7.1.1 Common requirements . 49
7.1.2 Circuit arrangement . 50
7.1.3 Documentation . 51
7.1.4 Transport routes . 51
7.1.5 Aisles and access areas . 52
7.1.6 Lighting . 53
7.1.7 Operational safety . 53
7.1.8 Labelling . 53
7.2 Outdoor electrical power installations of open design . 53
7.2.1 General . 53
7.2.2 Protective barrier clearances . 54
7.2.3 Protective obstacle clearances . 54
7.2.4 Boundary clearances . 55

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SIST EN IEC 61936-1:2021
– 4 – IEC 61936-1:2021 © IEC 2021
7.2.5 Minimum height over access area . 56
7.2.6 Clearances to buildings . 57
7.2.7 External fences or walls and access doors . 59
7.3 Indoor electrical power installations of open design . 59
7.4 Installation of prefabricated type-tested switchgear . 60
7.4.1 General . 60
7.4.2 Additional requirements for gas-insulated metal-enclosed switchgear . 60
7.5 Requirements for buildings . 62
7.5.1 General . 62
7.5.2 Structural provisions . 62
7.5.3 Rooms for switchgear . 63
7.5.4 Maintenance and operating areas . 63
7.5.5 Doors . 63
7.5.6 Draining of insulating liquids . 64
7.5.7 Heating, ventilation and air conditioning (HVAC) . 64
7.5.8 Buildings which require special consideration . 65
7.6 High voltage/low voltage prefabricated substations . 65
7.7 Electrical power installations on mast, pole and tower . 65
8 Safety measures . 65
8.1 General . 65
8.2 Protection against direct contact . 66
8.2.1 General . 66
8.2.2 Measures for protection against direct contact . 66
8.2.3 Protection requirements . 67
8.3 Means to protect persons in case of indirect contact . 68
8.4 Means to protect persons working on or near electrical power installations . 68
8.4.1 General . 68
8.4.2 Electrical equipment for isolating installations or apparatus . 68
8.4.3 Devices to prevent reclosing of isolating devices . 69
8.4.4 Devices for determining the de-energized state . 69
8.4.5 Devices for earthing and short-circuiting . 69
8.4.6 Equipment acting as protective barriers against adjacent live parts . 70
8.4.7 Storage of personal protection equipment . 71
8.5 Protection from danger resulting from arc fault . 71
8.6 Protection against direct lightning strokes . 71
8.7 Protection against fire . 72
8.7.1 General . 72
8.7.2 Transformers, reactors . 73
8.7.3 Cables . 79
8.7.4 Other equipment with flammable liquid . 79
8.8 Protection against leakage of insulating liquid and SF . 80
6
8.8.1 Insulating liquid leakage and subsoil water protection . 80
8.8.2 SF leakage . 82
6
8.8.3 Failure with loss of SF and its decomposition products . 83
6
8.9 Identification and marking . 83
8.9.1 General . 83
8.9.2 Information plates and warning plates . 84
8.9.3 Electrical hazard warning . 84

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SIST EN IEC 61936-1:2021
IEC 61936-1:2021 © IEC 2021 – 5 –
8.9.4 Electrical power installations with incorporated capacitors . 84
8.9.5 Emergency sign
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