IEC 61439-1:2009

Low-voltage switchgear and controlgear assemblies - Part 1: General rules

IEC 61439-1:2009 lays down the definitions and states the service conditions, construction requirements, technical characteristics and verification requirements for low-voltage switchgear and controlgear assemblies. This standard applies to low-voltage switchgear and controlgear assemblies (ASSEMBLIES) only when required by the relevant ASSEMBLY standard. This first edition of IEC 61439-1 standard cancels and replaces the fourth edition of IEC 60439-1:1999. Significant technical changes with respect to the last edition of IEC 60439-1. IEC 61439-1 is a pure "general rules" standard to be referred to by subsidiary product parts of the IEC 61439 series; the product standard replacing IEC 60439-1 is IEC 61439-2; the discrimination between type-tested assemblies (TTA) and partially type-tested assemblies (PTTA) is eliminated by the verification approach; three different but equivalent types of verification of requirements are introduced: verification by testing, verification by calculation/measurement, or verification by satisfying design rules; the requirements regarding temperature rise have been clarified; the rated diversity factor (RDF) is covered in more detail; requirements from the standard for empty enclosures for assemblies (IEC 62208) have been incorporated; the whole structure of the standard is aligned with its new function as "general rules" standard. However, when a dated reference to IEC 60439-1 is made in another Part of the IEC 60439 series of assembly standards not yet transferred into the new IEC 61439 series, the superseded IEC 60439-1 still applies.

Ensembles d'appareillage à basse tension - Partie 1: Règles générales

La CEI 61439-1:2009 formule les définitions et indique les conditions d'emploi, les exigences de construction, les caractéristiques techniques et les exigences de vérification pour les ensembles d'appareillage à basse tension. La présente norme s'applique, uniquement lorsque la norme d'ENSEMBLES applicable l'exige, aux ensembles d'appareillage à basse tension (ensembles). Cette première édition de la CEI 61439-1 annule et remplace la quatrième édition de la CEI 60439-1 :1999. Les modifications techniques sont les suivantes par rapport à la dernière édition de la CEI 60439-1. La CEI 61439-1 est une norme purement de "règles générales" devant être appelée par les parties de produit subsidiaires de la série CEI 61439; la norme de produit remplaçant la CEI 60439-1 est la CEI 61439-2; la distinction entre les ensembles de série (ES) et les ensembles dérivés de série (EDS) est éliminée par l'approche de vérification; trois types différents mais équivalents de vérification des exigences sont introduits: la vérification par essai, la vérification par calcul/mesure, ou la vérification par la satisfaction de règles de conception; les exigences concernant les échauffements ont été clarifiées; le facteur de diversité assigné (RDF) est traité avec de plus amples détails; les exigences des enveloppes vides destinées aux ensembles (CEI 62208) ont été incorporées; la totalité de la structure de la norme est alignée avec sa nouvelle fonction comme norme de "règles générales". Toutefois, lorsqu'une référence datée à la CEI 60439-1 apparaît dans une autre partie de la série CEI 60439 applicable aux ensembles qui n'a pas encore été transposée dans la nouvelle série CEI 61439, c'est la norme annulée CEI 60439-1 qui continue de s'appliquer.

General Information

• Status: Published
• Publication Date: 21-Jan-2009
• ICS: 29.130.20 - Low voltage switchgear and controlgear
• Technical Committee: SC 121B - Low-voltage switchgear and controlgear assemblies
• Current Stage: DELPUB - Deleted Publication
• Completion Date: 19-Aug-2011

Relations

• Revised: IEC 61439-1:2011 - Low-voltage switchgear and controlgear assemblies - Part 1: General rules
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC 61439-1
Edition 1.0 2009-01
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE


Low-voltage switchgear and controlgear assemblies –
Part 1: General rules

Ensembles d'appareillage à basse tension –
Partie 1: Règles générales

IEC 61439-1:2009

---------------------- Page: 1 ----------------------
THIS PUBLICATION IS COPYRIGHT PROTECTED
Copyright © 2009 IEC, Geneva, Switzerland

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 la CEI ou du Comité national de la CEI du pays du demandeur.
Si vous avez des questions sur le copyright de la CEI ou si vous désirez obtenir des droits supplémentaires sur cette
publication, utilisez les coordonnées ci-après ou contactez le Comité national de la CEI de votre pays de résidence.

IEC Central Office
3, rue de Varembé
CH-1211 Geneva 20
Switzerland
Email: [e-mail]
Web: www.iec.ch

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 corrigenda or an amendment might have been published.
ƒ Catalogue of IEC publications: www.iec.ch/searchpub
The IEC on-line Catalogue enables you to search by a variety of criteria (reference number, text, technical committee,…).
It also gives information on projects, withdrawn and replaced publications.
ƒ IEC Just Published: www.iec.ch/online_news/justpub
Stay up to date on all new IEC publications. Just Published details twice a month all new publications released. Available
on-line and also by email.
ƒ Electropedia: www.electropedia.org
The world's leading online dictionary of electronic and electrical terms containing more than 20 000 terms and definitions
in English and French, with equivalent terms in additional languages. Also known as the International Electrotechnical
Vocabulary online.
ƒ Customer Service Centre: www.iec.ch/webstore/custserv
If you wish to give us your feedback on this publication or need further assistance, please visit the Customer Service
Centre FAQ or contact us:
Email: [e-mail]
Tel.: [phone]
Fax: [phone]


A propos de la CEI
La Commission Electrotechnique Internationale (CEI) 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 CEI
Le contenu technique des publications de la CEI est constamment revu. Veuillez vous assurer que vous possédez
l’édition la plus récente, un corrigendum ou amendement peut avoir été publié.
ƒ Catalogue des publications de la CEI: www.iec.ch/searchpub/cur_fut-f.htm
Le Catalogue en-ligne de la CEI vous permet d’effectuer des recherches en utilisant différents critères (numéro de référence,
texte, comité d’études,…). Il donne aussi des informations sur les projets et les publications retirées ou remplacées.
ƒ Just Published CEI: www.iec.ch/online_news/justpub
Restez informé sur les nouvelles publications de la CEI. Just Published détaille deux fois par mois les nouvelles
publications parues. Disponible en-ligne et aussi par email.
ƒ Electropedia: www.electropedia.org
Le premier dictionnaire en ligne au monde de termes électroniques et électriques. Il contient plus de 20 000 termes et
définitions en anglais et en français, ainsi que les termes équivalents dans les langues additionnelles. Egalement appelé
Vocabulaire Electrotechnique International en ligne.
ƒ Service Clients: www.iec.ch/webstore/custserv/custserv_entry-f.htm
Si vous désirez nous donner des commentaires sur cette publication ou si vous avez des questions, visitez le FAQ du
Service clients ou contactez-nous:
Email: [e-mail]
Tél.: [phone]
Fax: [phone]

---------------------- Page: 2 ----------------------
IEC 61439-1
Edition 1.0 2009-01
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE


Low-voltage switchgear and controlgear assemblies –
Part 1: General rules

Ensembles d'appareillage à basse tension –
Partie 1: Règles générales

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
XF
CODE PRIX
ICS 29.130.20 ISBN 978-2-88910-515-1
® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale

---------------------- Page: 3 ----------------------
– 2 – 61439-1 © IEC:2009
CONTENTS
FOREWORD.8
INTRODUCTION.11
1 Scope.12
2 Normative references .12
3 Terms and definitions .15
3.1 General terms .15
3.2 Constructional units of ASSEMBLIES .16
3.3 External design of ASSEMBLIES.17
3.4 Structural parts of ASSEMBLIES .18
3.5 Conditions of installation of ASSEMBLIES.20
3.6 Insulation characteristics .20
3.7 Protection against electric shock .23
3.8 Characteristics .24
3.9 Verification .27
3.10 Manufacturer .27
4 Symbols and abbreviations.27
5 Interface characteristics .29
5.1 General .29
5.2 Voltage ratings .29
5.2.1 Rated voltage (U ) (of the ASSEMBLY) .29
n
5.2.2 Rated operational voltage (U ) (of a circuit of an ASSEMBLY).29
e
5.2.3 Rated insulation voltage (U ) (of a circuit of an ASSEMBLY) .29
i
5.2.4 Rated impulse withstand voltage (U ) (of the ASSEMBLY) .29
imp
5.3 Current ratings .29
5.3.1 Rated current of the ASSEMBLY (I ) .29
nA
5.3.2 Rated current of a circuit (I ) .30
nc
5.3.3 Rated diversity factor (RDF) .30
5.3.4 Rated peak withstand current (I ) .30
pk
5.3.5 Rated short-time withstand current (I ) (of a circuit of an ASSEMBLY) .30
cw
5.3.6 Rated conditional short-circuit current of an ASSEMBLY (I ).30
cc
5.4 Rated frequency (f ).31
n
5.5 Other characteristics .31
6 Information .31
6.1 ASSEMBLY designation marking .31
6.2 Documentation .31
6.2.1 Information relating to the ASSEMBLY .31
6.2.2 Instructions for handling, installation, operation and maintenance .32
6.3 Device and/or component identification .33
7 Service conditions .33
7.1 Normal service conditions .33
7.1.1 Ambient air temperature .33
7.1.2 Atmospheric conditions.33
7.1.3 Pollution degree .33
7.1.4 Altitude.34
7.2 Special service conditions .34

---------------------- Page: 4 ----------------------
61439-1 © IEC:2009 – 3 –
7.3 Conditions during transport, storage and installation .35
8 Constructional requirements .35
8.1 Strength of materials and parts.35
8.1.1 General .35
8.1.2 Protection against corrosion .35
8.1.3 Thermal stability .35
8.1.4 Resistance to ultra-violet radiation.35
8.1.5 Resistance of insulating materials to heat and fire .35
8.1.6 Mechanical strength .36
8.1.7 Lifting provision .36
8.2 Degree of protection provided by an ASSEMBLY enclosure .36
8.2.1 Protection against mechanical impact.36
8.2.2 Protection against contact with live parts, ingress of solid foreign
bodies and liquids.36
8.2.3 Degree of protection of removable parts .37
8.3 Clearances and creepage distances .37
8.3.1 General .37
8.3.2 Clearances .38
8.3.3 Creepage distances.38
8.4 Protection against electric shock .38
8.4.1 General .38
8.4.2 Basic protection.39
8.4.3 Fault protection .40
8.4.4 Limitation of steady-state touch current and charge.43
8.4.5 Operating and servicing conditions .43
8.5 Incorporation of switching devices and components .45
8.5.1 Fixed parts .45
8.5.2 Removable parts .45
8.5.3 Selection of switching devices and components.45
8.5.4 Installation of switching devices and components .46
8.5.5 Accessibility .46
8.5.6 Barriers .46
8.5.7 Direction of operation and indication of switching positions.46
8.5.8 Indicator lights and push-buttons .46
8.6 Internal electrical circuits and connections .47
8.6.1 Main circuits .47
8.6.2 Auxiliary circuits .47
8.6.3 Bare and insulated conductors .47
8.6.4 Selection and installation of non-protected live conductors to reduce
the possibility of short-circuits .48
8.6.5 Identification of the conductors of main and auxiliary circuits.48
8.6.6 Identification of the protective conductor (PE, PEN) and of the
neutral conductor (N) of the main circuits .48
8.7 Cooling.49
8.8 Terminals for external conductors.49
9 Performance requirements .50
9.1 Dielectric properties .50
9.1.1 General .50
9.1.2 Power-frequency withstand voltage .50

---------------------- Page: 5 ----------------------
– 4 – 61439-1 © IEC:2009
9.1.3 Impulse withstand voltage .51
9.1.4 Protection of surge protective devices .51
9.2 Temperature rise limits.51
9.3 Short-circuit protection and short-circuit withstand strength.51
9.3.1 General .51
9.3.2 Information concerning short-circuit withstand strength .52
9.3.3 Relationship between peak current and short-time current.52
9.3.4 Co-ordination of protective devices.52
9.4 Electromagnetic compatibility (EMC) .53
10 Design verification.53
10.1 General .53
10.2 Strength of materials and parts.54
10.2.1 General .54
10.2.2 Resistance to corrosion .54
10.2.3 Properties of insulating materials.55
10.2.4 Resistance to ultra-violet (UV) radiation.57
10.2.5 Lifting .57
10.2.6 Mechanical impact.58
10.2.7 Marking .58
10.3 Degree of protection of ASSEMBLIES .58
10.4 Clearances and creepage distances .58
10.5 Protection against electric shock and integrity of protective circuits.59
10.5.1 Effectiveness of the protective circuit.59
10.5.2 Effective earth continuity between the exposed conductive parts of
the ASSEMBLY and the protective circuit.59
10.5.3 Short-circuit withstand strength of the protective circuit .59
10.6 Incorporation of switching devices and components .60
10.6.1 General .60
10.6.2 Electromagnetic compatibility .60
10.7 Internal electrical circuits and connections .60
10.8 Terminals for external conductors.60
10.9 Dielectric properties .60
10.9.1 General .60
10.9.2 Power-frequency withstand voltage .60
10.9.3 Impulse withstand voltage .61
10.9.4 Testing of enclosures made of insulating material.63
10.10 Verification of temperature rise.63
10.10.1 General .63
10.10.2 Verification by testing with current.63
10.10.3 Derivation of ratings for similar variants .69
10.10.4 Verification by calculation.70
10.11 Short-circuit withstand strength.72
10.11.1 General .72
10.11.2 Circuits of ASSEMBLIES which are exempted from the verification of
the short-circuit withstand strength.73
10.11.3 Verification by the application of design rules.73
10.11.4 Verification by comparison with a reference design .73
10.11.5 Verification by test .73
10.12 Electromagnetic compatibility (EMC) .78

---------------------- Page: 6 ----------------------
61439-1 © IEC:2009 – 5 –
10.13 Mechanical operation.78
11 Routine verification.79
11.1 General .79
11.2 Degree of protection of enclosures .79
11.3 Clearances and creepage distances .79
11.4 Protection against electric shock and integrity of protective circuits .80
11.5 Incorporation of built-in components .80
11.6 Internal electrical circuits and connections.80
11.7 Terminals for external conductors .80
11.8 Mechanical operation.80
11.9 Dielectric properties.80
11.10 Wiring, operational performance and function .80
Annex A (normative) Minimum and maximum cross-section of copper conductors
suitable for connection to terminals for external conductors (see 8.8) .88
Annex B (normative) Method of calculating the cross-sectional area of protective
conductors with regard to thermal stresses due to currents of short duration .89
Annex C (informative) Items subject to agreement between the ASSEMBLY
Manufacturer and the User .90
Annex D (informative) Design verification .93
Annex E (informative) Rated diversity factor .94
Annex F (normative) Measurement of clearances and creepage distances . 103
Annex G (normative) Correlation between the nominal voltage of the supply system
and the rated impulse withstand voltage of the equipment . 109
Annex H (informative) Operating current and power loss of copper conductors . 111
Annex J (normative) Electromagnetic compatibility (EMC). 115
Annex K (normative) Protection by electrical separation. 122
Annex L (informative) Clearances and creepage distances for North American region . 125
Annex M (informative) North American temperature rise limits . 126
Bibliography.127

Figure E.1 – Typical ASSEMBLY.95
Figure E.2 – Example 1: Table E.1 – Functional unit loading for an ASSEMBLY with a
rated diversity factor of 0,8 .97
Figure E.3 – Example 2: Table E.1 – Functional unit loading for an ASSEMBLY with a
rated diversity factor of 0,8 .98
Figure E.4 – Example 3: Table E.1 – Functional unit loading for an ASSEMBLY with a
rated diversity factor of 0,8 .99
Figure E.5 – Example 4: Table E.1 – Functional unit loading for an ASSEMBLY with a
rated diversity factor of 0,8 .100
Figure E.6 – Example of average heating effect calculation . 101
Figure E.7 – Example graph for the relation between the equivalent RDF and the
parameters at intermittent duty at t = 0,5 s, I = 7*I at different cycle times . 102
1 1 2
Figure E.8 – Example graph for the relation between the equivalent RDF and the
parameters at intermittent duty at I = I (no starting overcurrent). 102
1 2
Figure F.1 – Measurement of ribs .104
Figure J.1 – Examples of ports .115

---------------------- Page: 7 ----------------------
– 6 – 61439-1 © IEC:2009
a)
Table 1 – Minimum clearances in air (8.3.2).82
Table 2 – Minimum creepage distances (8.3.3) .82
Table 3 – Cross-sectional area of a copper protective conductor (8.4.3.2.2) .83
Table 4 – Conductor selection and installation requirements (8.6.4).83
Table 5 – Minimum terminal capacity for copper protective conductors (PE, PEN) (8.8) .83
Table 6 – Temperature-rise limits (9.2) .84
a)
Table 7 – Values for the factor n (9.3.3).85
Table 8 – Power-frequency withstand voltage for main circuits (10.9.2) .85
Table 9 – Power-frequency withstand voltage for auxiliary and control circuits (10.9.2).85
Table 10 – Impulse withstand test voltages (10.9.3).85
Table 11 – Copper test conductors for rated currents up to 400 A inclusive
(10.10.2.3.2) .86
Table 12 – Copper test conductors for rated currents from 400 A to 4 000 A
(10.10.2.3.2) .86
Table 13 – Short-circuit verification by design rules: check list.87
Table 14 – Relationship between prospective fault current and diameter of copper wire .87
Table A.1 – Cross-section of copper conductors suitable for connection to terminals
for external conductors .88
Table B.1 – Values of k for insulated protective conductors not incorporated in cables,
or bare protective conductors in contact with cable covering.89
Table C.1 – Items subject to agreement between the ASSEMBLY manufacturer and the
User.90
Table D.1 – List of design verifications to be performed .93
Table E.1 – Examples of loading for an ASSEMBLY with a rated diversity factor of 0,8 .96
Table E.2 – Example of loading of a group of circuits (Section B – Figure E.1) with a
rated diversity factor of 0,9 .101
Table E.3 – Example of loading of a group of circuits (Subdistribution board – Figure
E.1) with a rated diversity factor of 0,9.101
Table F.1 – Minimum width of grooves.103
Table G.1 – Correspondence between the nominal voltage of the supply system and
the equipment rated impulse withstand voltage, in the case of overvoltage p
...