IEC 60364-4-42:2024
(Main)Low-voltage electrical installations - Part 4-42: Protection for safety - Protection against thermal effects
Low-voltage electrical installations - Part 4-42: Protection for safety - Protection against thermal effects
IEC 60364-4-42:2024 applies to electrical installations with regard to measures for the protection of persons, livestock and property against:
• thermal effects, risk of combustion or degradation of materials, and risk of burns caused by electrical equipment,
• flames in case of a fire hazard being propagated from electrical installations to other fire compartments segregated by barriers which are in the vicinity, and
• the impairment of the safe functioning of electrical equipment, including safety services due to thermal effects.
This group safety publication (GSP) focusing on safety essential requirements is primarily intended to be used as a product safety standard for the installations mentioned in the scope, but is also intended to be used by TCs in the preparation of publications for installations similar to those mentioned in the scope of this GSP, in accordance with the principles laid down in IEC Guide 104 and lSO/lEC Guide 51.
One of the responsibilities of a TC is, wherever applicable, to make use of basic safety publications and/or group safety publications in the preparation of its publications
This fourth edition cancels and replaces the third edition published in 2010 and Amendment 1:2014. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous edition:
a) the Scope now includes a new paragraph stating that IEC 60364-4-42 has become a group safety publication (GSP) following the Advisory Committee on Safety (ACOS) recommendation for approval of the group safety function "protection against thermal effects for any kind of low-voltage electrical installations" to TC 64; this GSP is primarily intended to be used as a product safety standard for the installations mentioned in the scope, but also to be used by TCs in the preparation of publications for installations similar to those mentioned in the scope of this GSP;
b) new terms and definitions have been added;
c) a new Subclause 421.6 regarding measures for preventing fires originating from the use of an electrical stove or cooker or hob has been added;
d) the previous Subclause 421.7 was expanded and moved to a new Clause 426: Additional protective measures against thermal effect for locations where consequences of fire are severe;
e) requirements for escape routes have been expanded and modified;
f) requirements for final circuits in BE2 locations have been expanded and modified;
g) requirements for locations with irreplaceable goods or with business critical facilities have been expanded and modified;
h) a new Clause 425 for protection against fire due to fault currents has been added;
i) a new Clause 427 for protection against assembly internal arc faults has been added
Installations électriques à basse tension - Partie 4-42: Protection pour assurer la sécurité - Protection contre les effets thermiques
IEC 60364-4-42 s’applique aux installations électriques en ce qui concerne les mesures de protection des personnes, du bétail et des biens contre:
• les effets thermiques, les risques de combustion ou de dégradation des matériaux, et les risques de brûlure provoqués par un matériel électrique;
• la propagation des flammes en cas de danger d’incendie, depuis les installations électriques vers d’autres compartiments feu séparés par des barrières se trouvant à proximité; et
• les atteintes à la sécurité de fonctionnement des matériels électriques, y compris les services de sécurité, dues aux effets thermiques.
La présente publication groupée de sécurité (GSP), qui met l’accent sur les exigences essentielles de sécurité, est avant tout destinée à être utilisée en tant que norme sécurité des produits pour les installations citées dans le domaine d’application, mais elle est également destinée à être utilisée par les CE dans le cadre de l’élaboration de publications pour des installations similaires à celles mentionnées dans le domaine d’application de cette GSP, conformément aux principes établis dans l’IEC Guide 104 et l’lSO/lEC Guide 51.
L’une des responsabilités d’un CE consiste, le cas échéant, à utiliser les publications fondamentales de sécurité et/ou les publications groupées de sécurité dans le cadre de l’élaboration de ses publications.
Cette quatrième édition annule et remplace la troisième édition parue en 2010 et son Amendement 1:2014. Cette édition constitue une révision technique.
Cette édition inclut les modifications techniques majeures suivantes par rapport à l’édition précédente:
a) le Domaine d’application contient maintenant un nouvel alinéa indiquant que l’IEC 60364 4 42 est devenue une publication groupée de sécurité (GSP, Group Safety Publication) qui suit la recommandation du Comité consultatif de la sécurité (ACOS, Advisory Committee on Safety) concernant l’approbation de la fonction groupée de sécurité "protection contre les effets thermiques pour tout type d’installation électrique basse tension" conformément au TC 64; cette GSP est avant tout destinée à être utilisée en tant que norme de sécurité des produits pour les installations citées dans le domaine d’application, mais elle est également destinée à être utilisée par les comités techniques dans le cadre de l’élaboration de publications pour des installations similaires à celles mentionnées dans le domaine d’application de cette GSP;
b) de nouveaux termes et de nouvelles définitions ont été ajoutés
c) un nouveau paragraphe 421.6, qui concerne les mesures pour la prévention des incendies dus à l’utilisation d’une cuisinière, d’un réchaud ou d’un plan de cuisson électrique, a été ajouté;
d) le paragraphe 421.7 précédent a été rallongé et déplacé vers un nouvel Article 426: Mesures de protection supplémentaires contre les effets thermiques pour les emplacements dans lesquels les conséquences d’un incendie sont graves;
e) les exigences concernant les issues de secours ont été développées et modifiées;
f) les exigences concernant les circuits terminaux dans les locaux BE2 ont été développées et modifiées;
g) les exigences concernant les emplacements contenant des biens irremplaçables ou les installations essentielles pour l’activité ont été développées et modifiées;
h) un nouvel Article 425 concernant la protection contre les incendies dus aux courants de défaut a été ajouté;
i) un nouvel Article 427 concernant les défauts d’arc internes dans un ensemble a été ajouté.
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Standards Content (Sample)
IEC 60364-4-42 ®
Edition 4.0 2024-11
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
HORIZONTAL PUBLICATION
PUBLICATION HORIZONTALE
Low-voltage electrical installations –
Part 4-42: Protection for safety – Protection against thermal effects
Installations électriques à basse tension –
Partie 4-42: Protection pour assurer la sécurité – Protection contre les effets
thermiques
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IEC 60364-4-42 ®
Edition 4.0 2024-11
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Low-voltage electrical installations –
Part 4-42: Protection for safety – Protection against thermal effects
Installations électriques à basse tension –
Partie 4-42: Protection pour assurer la sécurité – Protection contre les effets
thermiques
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.120.50, 91.140.50 ISBN 978-2-8322-9909-8
– 2 – IEC 60364-4-42:2024 © IEC 2024
CONTENTS
FOREWORD . 3
INTRODUCTION . 6
420 Protection against thermal effects . 7
420.1 Scope . 7
420.2 Normative references . 7
420.3 Terms and definitions . 8
421 Protection against fire caused by electrical equipment . 10
422 Requirements where external influences present particular risks during a fire . 11
423 Protection against burns. 16
424 Protection against overheating . 16
425 Protection against fire due to fault currents . 17
426 Additional protective measures against thermal effects for locations where
consequences of fire are severe . 17
427 Protection against assembly internal arc faults . 19
Annex A (informative) List of notes concerning certain countries . 21
Bibliography . 29
Table 1 – Temperature limits in normal service for accessible parts of equipment within
arm's reach . 16
Table A.1 – List of notes concerning certain countries . 21
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
LOW-VOLTAGE ELECTRICAL INSTALLATIONS –
Part 4-42: Protection for safety – Protection against thermal effects
FOREWORD
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shall not be held responsible for identifying any or all such patent rights.
IEC 60364-4-42 has been prepared by IEC technical committee 64: Electrical installations and
protection against electrical shock. It is an International Standard.
This fourth edition cancels and replaces the third edition published in 2010 and
Amendment 1:2014. This edition constitutes a technical revision.
– 4 – IEC 60364-4-42:2024 © IEC 2024
This edition includes the following significant technical changes with respect to the previous
edition:
a) the Scope now includes a new paragraph stating that IEC 60364-4-42 has become a group
safety publication (GSP) following the Advisory Committee on Safety (ACOS)
recommendation for approval of the group safety function "protection against thermal effects
for any kind of low-voltage electrical installations" to TC 64; this GSP is primarily intended
to be used as a product safety standard for the installations mentioned in the scope, but
also to be used by TCs in the preparation of publications for installations similar to those
mentioned in the scope of this GSP;
b) new terms and definitions have been added, for:
– arcing;
– arc fault;
– assembly internal arc fault;
– burn;
– combustion;
– escape route;
– final circuit arc fault;
– flame;
– flammable;
– flaming combustion;
– low-voltage switchgear and controlgear assembly;
c) a new Subclause 421.6 regarding measures for preventing fires originating from the use of
an electrical stove or cooker or hob has been added;
d) the previous Subclause 421.7 was expanded and moved to a new Clause 426: Additional
protective measures against thermal effect for locations where consequences of fire are
severe;
e) requirements for escape routes have been expanded and modified;
f) requirements for final circuits in BE2 locations have been expanded and modified;
g) requirements for locations with irreplaceable goods or with business critical facilities have
been expanded and modified;
h) a new Clause 425 for protection against fire due to fault currents has been added;
i) a new Clause 427 for protection against assembly internal arc faults has been added.
The text of this International Standard is based on the following documents:
Draft Report on voting
64/2686/FDIS 64/2697/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 Engl
...
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