IEC 61439-1:2011

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

IEC 61439-1:2011 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 cannot be used alone to specify an ASSEMBLY or used for a purpose of determining conformity. ASSEMBLIES shall comply with the relevant part of the IEC 61439 series; Parts 2 onwards. This standard applies to low-voltage switchgear and controlgear assemblies (ASSEMBLIES) only when required by the relevant ASSEMBLY standard as follows:
- ASSEMBLIES for which the rated voltage does not exceed 1 000 V in case of a.c. or 1 500 V in case of d.c.;
- stationary or movable ASSEMBLIES with or without enclosure;
- ASSEMBLIES intended for use in connection with the generation, transmission, distribution and conversion of electric energy, and for the control of electric energy consuming equipment;
- ASSEMBLIES designed for use under special service conditions, for example in ships and in rail vehicles provided that the other relevant specific requirements are complied with;
- ASSEMBLIES designed for electrical equipment of machines provided that the other relevant specific requirements are complied with. This second edition cancels and replaces the first edition published in 2009. It constitutes a technical revision. This second edition includes the following significant technical changes with respect to the last edition of IEC 61439-1:
- revision of service conditions in Clause 7;
- numerous changes regarding verification methods in Clause 10;
- modification of routine verification in respect of clearances and creepage distances (see 11.3);
- adaption of the tables in Annex C and Annex D to the revised requirements and verification methods;
- revision of the EMC requirements in Annex J;
- shifting of tables from Annex H to new Annex N;
- new Annex O with guidance on temperature rise verification;
- new Annex P with a verification method for short-circuit withstand strength (integration of the content of IEC/TR 61117);
- update of normative references;
- general editorial review.

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

La CEI 61439-1:2011 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 ne peut pas être utilisée de manière isolée pour spécifier un ENSEMBLE ou dans le but d'établir la conformité. Les ENSEMBLES doivent être conformes à la partie applicable de la série CEI 61439, à partir de la Partie 2. La présente norme s'applique, uniquement lorsque la norme d'ENSEMBLES applicable l'exige, aux ensembles d'appareillage à basse tension (ENSEMBLES) tels que décrits ci-après:
- ENSEMBLES dont la tension assignée ne dépasse pas 1 000 V en courant alternatif ou 1 500 V en courant continu;
- ENSEMBLES fixes ou mobiles avec ou sans enveloppe;
- ENSEMBLES destinés à être utilisés avec des équipements conçus pour la production, le transport, la distribution et la conversion de l'énergie électrique et la commande des matériels consommant de l'énergie électrique;
- ENSEMBLES conçus pour être utilisés dans des conditions spéciales d'emploi, par exemple, à bord de navires et de véhicules ferroviaires, sous réserve que les autres exigences spécifiques correspondantes soient respectées;
- ENSEMBLES conçus pour l'équipement électrique des machines sous réserve que les autres exigences spécifiques correspondantes soient respectées.
Cette deuxième édition annule et remplace la première édition parue en 2009, dont elle constitue une révision technique. Cette deuxième édition inclut les modifications techniques importantes suivantes par rapport à la dernière édition de la CEI 61439-1:
- révision des conditions de service de l'Article 7;
- de nombreuses modifications apportées aux méthodes de vérification de l'Article 10;
- modification de la vérification individuelle de série concernant les distances d'isolement et les lignes de fuite (voir 11.3);
- adaptation des tableaux de l'Annexe C et de l'Annexe D aux exigences révisées et aux méthodes de vérification;
- révision des exigences CEM de l'Annexe J;
- déplacement des tableaux de l'Annexe H à la nouvelle Annexe N;
- nouvelle Annexe O avec recommandation sur la vérification de l'échauffement;
- nouvelles Annexe P avec une méthode de vérification de la tenue aux courts-circuits (intégration du contenu de la CEI/TR 61117);
- mise à jour des références normatives;
- revue éditoriale générale.

General Information

• Status: Published
• Publication Date: 18-Aug-2011
• ICS: 29.130.20 - Low voltage switchgear and controlgear
• Technical Committee: SC 121B - Low-voltage switchgear and controlgear assemblies
• Drafting Committee: MT 2 - TC 121/SC 121B/MT 2
• Current Stage: DELPUB - Deleted Publication
• Completion Date: 05-May-2020

Relations

• Revises: IEC 61439-1:2009 - Low-voltage switchgear and controlgear assemblies - Part 1: General rules
• Effective Date: 05-Sep-2023
• Revised: IEC 61439-1:2020 - Low-voltage switchgear and controlgear assemblies - Part 1: General rules
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC 61439-1


®


Edition 2.0 2011-08



INTERNATIONAL



STANDARD



NORME
INTERNATIONALE
colour
inside


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

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


IEC 61439-1:2011

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IEC 61439-1


®


Edition 2.0 2011-08



INTERNATIONAL



STANDARD



NORME
INTERNATIONALE
colour
inside


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
CODE PRIX XG
ICS 29.130.20 ISBN 978-2-88912-634-7

® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale

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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 . 17

3.3 External design of ASSEMBLIES . 18
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 . 25
3.9 Verification . 27
3.10 Manufacturer/user . 28
4 Symbols and abbreviations . 28
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 . 30
5.3.1 Rated current of the ASSEMBLY (I ) . 30
nA
5.3.2 Rated current of a circuit (I ) . 30
nc
5.3.3 Rated peak withstand current (I ) . 30
pk
5.3.4 Rated short-time withstand current (I ) (of a circuit of an ASSEMBLY) . 30
cw
5.3.5 Rated conditional short-circuit current of an ASSEMBLY (I ) . 30
cc
5.4 Rated diversity factor (RDF) . 31
5.5 Rated frequency (f ) . 31
n
5.6 Other characteristics . 31

6 Information . 32
6.1 ASSEMBLY designation marking . 32
6.2 Documentation . 32
6.2.1 Information relating to the ASSEMBLY . 32
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 Humidity conditions . 33
7.1.3 Pollution degree . 33
7.1.4 Altitude . 34
7.2 Special service conditions . 34
7.3 Conditions during transport, storage and installation . 35

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61439-1 © IEC:2011 – 3 –


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 Properties of insulating materials . 35

8.1.4 Resistance to ultra-violet radiation . 36

8.1.5 Mechanical strength . 36

8.1.6 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 water . 36
8.2.3 ASSEMBLY with 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 . 39
8.4.1 General . 39
8.4.2 Basic protection . 39
8.4.3 Fault protection . 40
8.4.4 Protection by total insulation . 42
8.4.5 Limitation of steady-state touch current and charge . 43
8.4.6 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 . 46
8.5.4 Installation of switching devices and components . 46
8.5.5 Accessibility . 46
8.5.6 Barriers . 47
8.5.7 Direction of operation and indication of switching positions. 47
8.5.8 Indicator lights and push-buttons . 47
8.6 Internal electrical circuits and connections . 47
8.6.1 Main circuits . 47

8.6.2 Auxiliary circuits . 48
8.6.3 Bare and insulated conductors . 48
8.6.4 Selection and installation of non-protected live conductors to reduce
the possibility of short-circuits . 49
8.6.5 Identification of the conductors of main and auxiliary circuits . 49
8.6.6 Identification of the protective conductor (PE, PEN) and of the
neutral conductor (N) of the main circuits . 49
8.7 Cooling . 49
8.8 Terminals for external conductors . 49
9 Performance requirements . 51
9.1 Dielectric properties . 51
9.1.1 General . 51
9.1.2 Power-frequency withstand voltage . 51
9.1.3 Impulse withstand voltage . 51

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9.1.4 Protection of surge protective devices . 51

9.2 Temperature rise limits . 52

9.3 Short-circuit protection and short-circuit withstand strength . 52

9.3.1 General . 52

9.3.2 Information concerning short-circuit withstand strength . 52

9.3.3 Relationship between peak current and short-time current . 53

9.3.4 Co-ordination of protective devices . 53

9.4 Electromagnetic compatibility (EMC) . 53

10 Design verification . 54


10.1 General . 54
10.2 Strength of materials and parts . 55
10.2.1 General . 55
10.2.2 Resistance to corrosion . 55
10.2.3 Properties of insulating materials . 56
10.2.4 Resistance to ultra-violet (UV) radiation. 58
10.2.5 Lifting . 58
10.2.6 Mechanical impact . 59
10.2.7 Marking . 59
10.3 Degree of protection of ASSEMBLIES . 59
10.4 Clearances and creepage distances . 59
10.5 Protection against electric shock and integrity of protective circuits . 60
10.5.1 Effectiveness of the protective circuit. 60
10.5.2 Effective earth continuity between the exposed conductive parts of
the ASSEMBLY and the protective circuit . 60
10.5.3 Short-circuit withstand strength of the protective circuit . 60
10.6 Incorporation of switching devices and components . 61
10.6.1 General . 61
10.6.2 Electromagnetic compatibility . 61
10.7 Internal electrical circuits and connections . 61
10.8 Terminals for external conductors . 61
10.9 Dielectric properties . 61
10.9.1 General . 61
10.9.2 Power-frequency withstand voltage . 61
10.9.3 Impulse withstand voltage . 62
10.9.4 Testing of enclosures made of insulating material . 64

10.9.5 External operating handles of insulating material . 64
10.10 Verification of temperature rise . 64
10.10.1 General . 64
10.10.2 Verification by testing . 64
10.10.3 Derivation of ratings for similar variants . 70
10.10.4 Verification assessment . 71
10.11 Short-circuit withstand strength . 74
10.11.1 General . 74
10.11.2 Circuits of ASSEMBLIES which are exempted from the verification of
the short-circuit withstand strength . 74
10.11.3 Verification by comparison with a reference design – Utilising a
check list . 75
10.11.4 Verification by comparison with a reference design – Utilising
calculation . 75
10.11.5 Verification by test . 75

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61439-1 © IEC:2011 – 5 –


10.12 Electromagnetic compatibility (EMC) . 80

10.13 Mechanical operation . 80

11 Routine verification . 80


11.1 General . 80

11.2 Degree of protection of enclosures . 81

11.3 Clearances and creepage distances . 81

11.4 Protection against electric shock and integrity of protective circuits . 81

11.5 Incorporation of built-in components . 81

11.6 Internal electrical circuits and connections . 81


11.7 Terminals for external conductors . 81
11.8 Mechanical operation . 82
11.9 Dielectric properties . 82
11.10 Wiring, operational performance and function . 82
Annex A (normative) Minimum and maximum cross-section of copper conductors
suitable for connection to terminals for external conductors (see 8.8) . 90
Annex B (normative) Method of calculating the cross-sectional area of protective
conductors with regard to thermal stresses due to currents of short duration . 91
Annex C (informative) User information template . 92
Annex D (informative) Design verification . 96
Annex E (informative) Rated diversity factor . 97
Annex F (normative) Measurement of clearances and creepage distances . 106
Annex G (normative) Correlation between the nominal voltage of the supply system
and the rated impulse withstand voltage of the equipment . 111
Annex H (informative) Operating current and power loss of copper conductors . 113
Annex I (Void) . 115
Annex J (normative) Electromagnetic compatibility (EMC). 116
Annex K (normative) Protection by electrical separation. 123
Annex L (informative) Clearances and creepage distances for North American region . 126
Annex M (informative) North American temperature rise limits . 127
Annex N (normative) Operating current and power loss of bare copper bars . 128
Annex O (informative) Guidance on temperature rise verification . 130
Annex P (normative) Verification of the short-circuit withstand strength of busbar
structures by comparison with a tested reference design by calculation . 135
Bibliography . 139


Figure E.1 – Typical ASSEMBLY . 98
Figure E.2 – Example 1: Table E.1 – Functional unit loading for an ASSEMBLY with a
rated diversity factor of 0,8 . 100
Figure E.3 – Example 2: Table E.1 – Functional unit loading for an ASSEMBLY with a
rated diversity factor of 0,8 . 101
Figure E.4 – Example 3: Table E.1 – Functional unit loading for an ASSEMBLY with a
rated diversity factor of 0,8 . 102
Figure E.5 – Example 4: Table E.1 – Functional unit loading for an ASSEMBLY with a
rated diversity factor of 0,8 . 103
Figure E.6 – Example of average heating effect calculation . 104
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 . 105
1 1 2

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Figure E.8 – Example graph for the relation between the equivalent RDF and the

parameters at intermittent duty at I = I (no starting overcurrent) . 105
1 2

Figure F.1 – Measurement of ribs . 110


Figure J.1 – Examples of ports . 116

Figure O.1 – Temperature rise verification methods . 134

Figure P.1 – Tested busbar structure (TS) . 135


Figure P.2 – Non tested busbar structure (NTS) . 136

Figure P.3 – Angular busbar configuration with supports at the corners . 138



a
Table 1 – Minimum clearances in air (8.3.2) . 82
Table 2 – Minimum creepage distances (8.3.3) . 83
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) . 84
Table 5 – Minimum terminal capacity for copper protective conductors (PE, PEN) (8.8) . 84
Table 6 – Temperature-rise limits (9.2) . 85
a
Table 7 – Values for the factor n (9.3.3) . 86
Table 8 – Power-frequency withstand voltage for main circuits (10.9.2) . 86
Table 9 – Power-frequency withstand voltage for auxiliary and control circuits (10.9.2) . 86
Table 10 – Impulse withstand test voltages (10.9.3) . 87
Table 11 – Copper test conductors for rated currents up to 400 A inclusive
(10.10.2.3.2) . 87
Table 12 – Copper test conductors for rated currents from 400 A to 4 000 A
(10.10.2.3.2) . 88
Table 13 – Short-circuit
...