IEC 61439-3:2012

Low-voltage switchgear and controlgear assemblies - Part 3: Distribution boards intended to be operated by ordinary persons (DBO)

IEC 61439-3:2012 defines the specific requirements for distribution boards intended to be operated by ordinary persons (DBO). DBOs have the following criteria:
- intended to be operated by ordinary persons (e.g. switching operations and replacing fuse-links), e.g. in domestic (household) applications;
- outgoing circuits contain protective devices, intended to be operated by ordinary persons, complying e.g. with IEC 60898-1, IEC 61008, IEC 61009, IEC 62423 and IEC 60269-3;
- rated voltage to earth does not exceed 300 V a.c.;
- rated current (Inc) of the outgoing circuits does not exceed 125 A and the rated current (InA) of the DBO does not exceed 250 A;
- intended for the distribution of electrical energy;
- enclosed, stationary;
- for indoor or outdoor use.
This first edition cancels and replaces the first edition of IEC 60439-3 (1990), Amendment 1 (1993) and Amendment 2 (2001). It constitutes a technical revision. This edition includes the following significant technical changes with respect to IEC 60439-3 (including the amendments):
- alignment with IEC 61439-1:2011.
This publication is to be read in conjunction with IEC 61439-1:2011. The contents of the corrigenda of September 2013 and March 2019 have been included in this copy.

Ensembles d'appareillage à basse tension - Partie 3: Tableaux de répartition destinés à être utilisés par des personnes ordinaires (DBO)

La CEI 61439-3:2012 définit les exigences spécifiques applicables aux tableaux de répartition destinés à être utilisés par des personnes ordinaires (DBO). Les DBO satisfont les critères suivants:
- destinés à être utilisés par des personnes ordinaires (par exemple, pour man uvrer des appareils de commande et remplacer des éléments de fusible), par exemple dans des applications domestiques;
- les circuits de départ contiennent des dispositifs de protection, destinés à être utilisés par des personnes ordinaires, satisfaisant par exemple à la CEI 60898-1, la CEI 61008, la CEI 61009, la CEI 62423 et la CEI 60269-3;
- la tension assignée par rapport à la terre ne dépasse pas 300 V en courant alternatif;
- le courant assigné (Inc) des circuits de départ ne dépasse pas 125 A, et le courant assigné (InA) du DBO ne dépasse pas 250 A;
- destinés à la distribution d'énergie électrique;
- sous enveloppe, fixes;
- pour utilisation intérieure ou extérieure.
Cette première édition annule et remplace la première édition de la CEI 60439-3 (1990), l'Amendement 1 (1993) et l'Amendement 2 (2001). Elle constitue une révision technique. Cette édition inclut les modifications techniques majeures suivantes par rapport à la CEI 60439-3 (y compris les amendements):
- alignement avec la CEI 61439-1:2011.
Cette publication doit être lue conjointement avec la CEI 61439-1:2011. Le contenu du corrigendum de septembre 2013 et mars 2019 a été pris en considération dans cet exemplaire.

General Information

• Status: Published
• Publication Date: 15-Feb-2012
• ICS: 01 - GENERALITIES. TERMINOLOGY. STANDARDIZATION. DOCUMENTATION
• ICS: 29.130.20 - Low voltage switchgear and controlgear
• Technical Committee: SC 121B - Low-voltage switchgear and controlgear assemblies
• Drafting Committee: MT 4 - TC 121/SC 121B/MT 4

Relations

• Replaces: IEC 60439-3:1990 - Low-voltage switchgear and controlgear assemblies. Part 3: Particular requirements for low-voltage switchgear and controlgear assemblies intended to be installed in places where unskilled persons have access for their use - Distribution boards
• Effective Date: 05-Sep-2023
• Replaces: IEC 60439-3:1990/AMD2:2001 - Amendment 2 - Low-voltage switchgear and controlgear assemblies. Part 3: Particular requirements for low-voltage switchgear and controlgear assemblies intended to be installed in places where unskilled persons have access for their use - Distribution boards
• Effective Date: 05-Sep-2023
• Corrected By: IEC 61439-3:2012/COR2:2019 - Corrigendum 2 - Low-voltage switchgear and controlgear assemblies - Part 3: Distribution boards intended to be operated by ordinary persons (DBO)
• Effective Date: 05-Sep-2023
• Corrected By: IEC 61439-3:2012/COR1:2013 - Corrigendum 1 - Low-voltage switchgear and controlgear assemblies - Part 3: Distribution boards intended to be operated by ordinary persons (DBO)
• Effective Date: 05-Sep-2023
• Revised: IEC 61439-3:2024 - Low-voltage switchgear and controlgear assemblies - Part 3: Distribution boards intended to be operated by ordinary persons (DBO)
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC 61439-3 ®
Edition 1.0 2012-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Low-voltage switchgear and controlgear assemblies –
Part 3: Distribution boards intended to be operated by ordinary persons (DBO)

Ensembles d'appareillage à basse tension –
Partie 3: Tableaux de répartition destinés à être utilisés par des personnes
ordinaires (DBO)
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IEC 61439-3 ®
Edition 1.0 2012-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Low-voltage switchgear and controlgear assemblies –

Part 3: Distribution boards intended to be operated by ordinary persons (DBO)

Ensembles d'appareillage à basse tension –

Partie 3: Tableaux de répartition destinés à être utilisés par des personnes

ordinaires (DBO)
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX R
ICS 29.130.20 ISBN 978-2-88912-922-5

– 2 – 61439-3 © IEC:2012
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 6
4 Symbols and abbreviations . 6
5 Interface characteristics . 6
6 Information . 7
7 Service conditions . 7
8 Constructional requirements . 8
9 Performance requirements . 9
10 Design verification . 9
11 Routine verification . 12
Annexes . 15
Annex AA (informative) Items subject to agreement between the ASSEMBLY
manufacturer and the user . 16
Bibliography . 20

Figure 101 – Example of temperature rise verification by test of a complete DBO
as in 10.10.2.3.6 . 14

Table 101 – Values of assumed loading . 12
Table 102 – Tightening torque values for the verification of mechanical strength . 13
Table AA.1 – Items subject to agreement between the ASSEMBLY manufacturer and the
user . 16

61439-3 © IEC:2012 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
LOW-VOLTAGE SWITCHGEAR AND CONTROLGEAR ASSEMBLIES –

Part 3: Distribution boards intended to be operated
by ordinary persons (DBO)
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
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2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 61439-3 has been prepared by subcommittee 17D: Low-voltage
switchgear and controlgear assemblies, of IEC technical committee 17: Switchgear and
controlgear.
This first edition cancels and replaces the first edition of IEC 60439-3 (1990), Amendment 1
(1993) and Amendment 2 (2001). It constitutes a technical revision.
This edition includes the following significant technical changes with respect to IEC 60439-3
(including the amendments):
– alignment with IEC 61439-1:2011.

– 4 – 61439-3 © IEC:2012
The text of this standard is based on the following documents:
FDIS Report on voting
17D/448/FDIS 17D/450/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This standard is to be read in conjunction with IEC 61439-1. The provisions of the general
rules dealt with in IEC 61439-1 (hereinafter referred to as Part 1) are applicable to this
standard where they are specifically cited. When this standard states “addition” “modification”
or “replacement”, the relevant text in Part 1 is to be adapted accordingly.
Subclauses that are numbered with a 101 (102, 103, etc.) suffix are additional to the same
subclause in Part 1.
Tables and figures in this Part 3 that are new are numbered starting with 101.
New annexes in this Part 3 are lettered AA, BB, etc.
The “in some countries” notes regarding differing national practices are contained in the
following subclauses:
3.1.102
6.1
8.2.1
8.5.3
8.6.1
8.8
A list of all parts of the IEC 61439 series, under the general title Low-voltage switchgear and
controlgear assemblies can be found on the IEC website.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
The contents of the corrigenda of September 2013 and March 2019 have been included in
this copy.
61439-3 © IEC:2012 – 5 –
LOW-VOLTAGE SWITCHGEAR AND CONTROLGEAR ASSEMBLIES –

Part 3: Distribution boards intended to be operated
by ordinary persons (DBO)
1 Scope
This part of IEC 61439 defines the specific requirements for distribution boards intended to be
operated by ordinary persons (DBO).
DBOs have the following criteria:
– intended to be operated by ordinary persons (e.g. switching operations and replacing
fuse-links), e.g. in domestic (household) applications;
– outgoing circuits contain protective devices, intended to
...