IEC 62991:2022

Particular requirements for source switching equipment (SSE)

IEC 62991:2022 applies to source switching equipment, hereafter referred to as SSE, for household and similar uses, primarily intended to be used for energy efficiency (EE) purposes with local production and/or storage of energy.
SSE is intended to be installed in low voltage prosumer electrical installations (PEI) to deliver the electrical energy:
either to current-using equipment (direct feeding mode or island mode);
or to the grid (reverse feeding mode).

Exigences particulières relatives au matériel de commutation de source (SSE)

L'IEC 62291:2022 s'applique au matériel de commutation de source, ci-après dénommé "SSE", destiné à un usage domestique ou analogue, essentiellement prévu pour être utilisé pour les besoins de l'efficacité énergétique (EE) avec la production locale et/ou le stockage local de l'énergie.
Le SSE est destiné à être installé dans des installations électriques de prosommateurs (PEI - prosumer electrical installation) à basse tension pour délivrer l'énergie électrique:
au matériel d'utilisation (mode d'alimentation directe ou mode en réseau séparé);
ou au réseau (mode d'alimentation inverse).

General Information

• Status: Published
• Publication Date: 06-Dec-2022
• ICS: 03.100.70 - Management systems
• ICS: 27.015 - Energy efficiency. Energy conservation in general
• ICS: 29.020 - Electrical engineering in general
• Technical Committee: SC 23K - Electrical Energy Efficiency products
• Drafting Committee: WG 1 - TC 23/SC 23K/WG 1
• Current Stage: PPUB - Publication issued
• Start Date: 06-Jan-2023
• Completion Date: 07-Dec-2022

Standards Content (Sample)

IEC 62991 ®
Edition 1.0 2022-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Particular requirements for source switching equipment (SSE)

Exigences particulières relatives au matériel de commutation de source (SSE)

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
either IEC or IEC's member National Committee in the country of the requester. If you have any questions about IEC
copyright or have an enquiry about obtaining additional rights to this publication, please contact the address below or
your local IEC member National Committee for further information.

Droits de reproduction réservés. Sauf indication contraire, aucune partie de cette publication ne peut être reproduite
ni utilisée sous quelque forme que ce soit et par aucun procédé, électronique ou mécanique, y compris la photocopie
et les microfilms, sans l'accord écrit de l'IEC ou du Comité national de l'IEC du pays du demandeur. Si vous avez des
questions sur le copyright de l'IEC ou si vous désirez obtenir des droits supplémentaires sur cette publication, utilisez
les coordonnées ci-après ou contactez le Comité national de l'IEC de votre pays de résidence.

IEC Secretariat Tel.: [phone]
3, rue de Varembé [e-mail]
CH-1211 Geneva 20 www.iec.ch
Switzerland
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.
Electropedia - www.electropedia.org
IEC Just Published - webstore.iec.ch/justpublished
The world's leading online dictionary on electrotechnology,
Stay up to date on all new IEC publications. Just Published
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.
Also known as the International Electrotechnical Vocabulary

(IEV) online.
IEC Customer Service Centre - webstore.iec.ch/csc
If you wish to give us your feedback on this publication or
need further assistance, please contact the Customer Service
Centre: [e-mail].
A propos de l'IEC
La Commission Electrotechnique Internationale (IEC) est la première organisation mondiale qui élabore et publie des
Normes internationales pour tout ce qui a trait à l'électricité, à l'électronique et aux technologies apparentées.

A propos des publications IEC
Le contenu technique des publications IEC est constamment revu. Veuillez vous assurer que vous possédez l’édition la
plus récente, un corrigendum ou amendement peut avoir été publié.

Recherche de publications IEC - IEC Products & Services Portal - products.iec.ch
webstore.iec.ch/advsearchform Découvrez notre puissant moteur de recherche et consultez
La recherche avancée permet de trouver des publications IEC gratuitement tous les aperçus des publications. Avec un
en utilisant différents critères (numéro de référence, texte, abonnement, vous aurez toujours accès à un contenu à jour
comité d’études, …). Elle donne aussi des informations sur adapté à vos besoins.
les projets et les publications remplacées ou retirées.

Electropedia - www.electropedia.org
IEC Just Published - webstore.iec.ch/justpublished
Le premier dictionnaire d'électrotechnologie en ligne au
Restez informé sur les nouvelles publications IEC. Just
monde, avec plus de 22 300 articles terminologiques en
Published détaille les nouvelles publications parues.
anglais et en français, ainsi que les termes équivalents dans
Disponible en ligne et une fois par mois par email.
19 langues additionnelles. Egalement appelé Vocabulaire

Electrotechnique International (IEV) en ligne.
Service Clients - webstore.iec.ch/csc

Si vous désirez nous donner des commentaires sur cette
publication ou si vous avez des questions contactez-nous:
[e-mail].
IEC 62991 ®
Edition 1.0 2022-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Particular requirements for source switching equipment (SSE)

Exigences particulières relatives au matériel de commutation de source (SSE)

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 03.100.70; 27.015; 29.020 ISBN 978-2-8322-6198-9

– 2 – IEC 62991:2022 © IEC 2022
CONTENTS
FOREWORD . 8
INTRODUCTION . 10
1 Scope . 12
2 Normative references . 13
3 Terms and definitions . 15
3.1 General definitions . 15
3.2 Additional definitions for NC-SSE and SSE control units (controllers) of
C-SSE . 25
3.3 Additional definitions dedicated to C-SSE . 26
4 Classification . 27
4.1 According to the method of operation . 27
4.2 According to the construction . 27
4.3 According to the kind of current . 28
4.4 According to the number of switched poles . 28
4.5 According to the type of terminals . 28
4.6 According to the SSE's intended application . 28
4.7 According to coupling method . 28
4.7.1 SSE with synchronization . 28
4.7.2 SSE with interlock . 28
4.7.3 SSE with synchronization and interlock . 28
4.8 According to the transition type . 28
4.9 According to the possibility to select sources . 28
4.10 According to the utilization category . 28
4.11 According to the possibility to provide an OFF position . 28
4.12 According to the method of mounting . 29
4.13 According to the protection against external influences . 29
4.14 According to functional categories . 29
5 Characteristics . 31
5.1 General . 31
5.2 Type and characteristics of the equipment . 32
5.3 Characteristics of NC-SSE . 32
5.3.1 General . 32
5.3.2 Characteristics of main circuits . 32
5.3.3 Utilization categories . 35
5.3.4 Characteristics of control circuits, including electrical interlocks . 35
5.3.5 Characteristics of auxiliary circuits . 37
5.4 Characteristics of C-SSE . 37
5.4.1 General . 37
5.4.2 Characteristics of main circuits . 37
5.4.3 Utilization categories . 38
5.4.4 Characteristics of control circuits, including electrical interlocks . 38
5.4.5 Characteristics of auxiliary circuits . 39
6 Markings and product information . 39
7 Standard conditions for operation in service . 40
7.1 General . 40
7.2 Ambient temperature range in normal use . 41

7.3 Relative humidity . 41
7.4 Altitude . 41
7.5 Conditions of installation . 41
7.6 Pollution degree . 41
8 Requirements for construction and operation . 41
8.1 General . 41
8.2 Mechanical design . 42
8.2.1 General . 42
8.2.2 Constructional requirements . 42
8.2.3 Mechanism and operating means. 44
8.2.4 Clearances and creepage distances and distances through sealing
compound . 46
8.2.5 Screws, current-carrying parts and connections . 49
8.2.6 Terminals for external conductors . 50
8.3 Protection against electric shock . 52
8.4 Dielectric properties . 52
8.4.1 General . 52
8.4.2 Dielectric properties . 52
8.5 Temperature-rise . 52
8.6 Making and breaking capacity . 53
8.7 Performances . 54
8.7.1 General . 54
8.7.2 Operating conditions . 55
8.7.3 Operational performance . 57
8.8 Resistance to heat . 58
8.9 Resistance of insulating material to abnormal heat and to fire . 58
8.10 Resistance to rusting . 59
8.11 Coordination with short-circuit protective devices (SCPDs) . 59
8.12 EMC . 59
8.13 Resistance to abnormal conditions .
...