FprEN IEC 61439-3:2023

SLOVENSKI STANDARD
oSIST prEN IEC 61439-3:2022
01-oktober-2022
Sestavi nizkonapetostnih stikalnih in krmilnih naprav - 3. del: Električni
razdelilniki, s katerimi lahko ravnajo nestrokovnjaki (DBO)
Low-voltage switchgear and controlgear assemblies - Part 3: Distribution boards
intended to be operated by ordinary persons (DBO)
Niederspannungs-Schaltgerätekombinationen - Teil 3: Installationsverteiler für die
Bedienung durch Laien (DBO)
Ensembles d'appareillage à basse tension - Partie 3: Tableaux de répartition destinés à
être utilisés par des personnes ordinaires (DBO)
Ta slovenski standard je istoveten z: prEN IEC 61439-3:2022
ICS:
29.130.20 Nizkonapetostne stikalne in Low voltage switchgear and
krmilne naprave controlgear
oSIST prEN IEC 61439-3:2022 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

oSIST prEN IEC 61439-3:2022
oSIST prEN IEC 61439-3:2022
121B/159/CDV
COMMITTEE DRAFT FOR VOTE (CDV)
PROJECT NUMBER:
IEC 61439-3 ED2
DATE OF CIRCULATION: CLOSING DATE FOR VOTING:
2022-07-15 2022-10-07
SUPERSEDES DOCUMENTS:
121B/139/CD, 121B/158/CC
IEC SC 121B : LOW-VOLTAGE SWITCHGEAR AND CONTROLGEAR ASSEMBLIES
SECRETARIAT: SECRETARY:
Germany Mr Jörg Hußmann
OF INTEREST TO THE FOLLOWING COMMITTEES: PROPOSED HORIZONTAL STANDARD:

TC 18,TC 44,TC 64,SC 121A
Other TC/SCs are requested to indicate their interest, if
any, in this CDV to the secretary.
FUNCTIONS CONCERNED:
EMC ENVIRONMENT QUALITY ASSURANCE SAFETY
SUBMITTED FOR CENELEC PARALLEL VOTING NOT SUBMITTED FOR CENELEC PARALLEL VOTING
Attention IEC-CENELEC parallel voting
The attention of IEC National Committees, members of
CENELEC, is drawn to the fact that this Committee Draft
for Vote (CDV) is submitted for parallel voting.
The CENELEC members are invited to vote through the
CENELEC online voting system.
This document is still under study and subject to change. It should not be used for reference purposes.
Recipients of this document are invited to submit, with their comments, notification of any relevant patent rights of
which they are aware and to provide supporting documentation.

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

PROPOSED STABILITY DATE: 2026
NOTE FROM TC/SC OFFICERS:
download this electronic file, to make a copy and to print out the content for the sole purpose of preparing National
Committee positions. You may not copy or "mirror" the file or printed version of the document, or any part of it, for
any other purpose without permission in writing from IEC.

oSIST prEN IEC 61439-3:2022
IEC CDV 61439-3 © IEC 2022 2 121B/159/CDV

1 CONTENTS
2 FOREWORD . 4
3 1 Scope . 6
4 2 Normative references . 6
5 3 Terms and definitions . 7
6 3.1 General terms . 7
7 4 Symbols and abbreviations . 8
8 5 Interface characteristics . 8
9 5.1 General . 8
10 5.2.4 Rated impulse withstand voltage (U ) (of the assembly ). 8
imp
11 5.4 Rated diversity factor (RDF) . 8
12 6 Information . 8
13 6.1 Assembly designation marking . 8
14 6.2.2 Instructions for handling, installation, operation and maintenance . 9
15 6.3 Device and/or component identification . 9
16 7 Service conditions . 9
17 7.1.2 Pollution degree . 9
18 8 Constructional requirements . 9
19 8.1.3.2.2 Resistance of insulating materials to normal heat . 9
20 8.2.1 Protection against mechanical impact (IK code) . 9
21 8.2.2 Protection against contact with live parts, ingress of solid foreign bodies and
22 water (IP code) . 9
23 IP 2XC shall be maintained when operating devices e.g. switching and operating
24 test buttons in normal use. The degree of protection can be temporarily
25 reduced when permitted in a product standard for use by ordinary / unskilled
26 persons e.g. IEC 60269-3 for replacing a fuse-link, the degree of protection
27 may temporarily be reduced to IP1X. . 9
28 8.4.2.3 Barriers or enclosures . 9
29 8.5.3 Selection of switching devices and components . 10
30 8.6.1 Main circuits . 10
31 8.8 Terminals for external cables . 10
32 9 Performance requirements . 10
33 9.1.1 General . 10
34 10 Design verification . 10
35 10.2.2.2Severity test A . 10
36 10.2.2.4Results to be obtained . 11
37 10.2.3.2.1 Verification by test . 11
38 10.2.6 Verification of protection against mechanical impact (IK code) . 11
39 10.2.7.1 Verification by test . 12
40 10.10.2.2.3 Functional units . 12
41 10.10.2.3.1General . 13
42 10.10.2.3.6 Verification considering individual functional units
43 separately and the complete assembly . 13
44 10.10.2.3.7 Verification considering individual functional units and the
45 main and distribution busbars separately as well as the complete assembly . 13
46 10.10.3.2Assemblies . 14
47 10.10.4.2.3Results to be obtained . 14
48 10.10.4.3.2Results to be obtained . 14
49 10.11.5.3.3Incoming circuit and main busbars . 14
50 11 Routine verification . 15

oSIST prEN IEC 61439-3:2022
IEC CDV 61439-3 © IEC 2022 3 121B/159/CDV

51 Annexes. 18
52 Annex AA (informative) Items subject to agreement between the DBO manufacturer
53 and the user . 19
54 Annex BB (informative) Effects upon a DBO design and related ratings, instructions
55 etc when used in a prosumer’s electrical installation (PEI) . 25
56 Annex CC (informative) . 26
57 Annex DD (informative) List of notes concerning certain countries . 27
58 Bibliography . 40
60 UK Figure 101 – Example of temperature rise verification by test of a complete
61 split-load DBO as in 10.10.2.3.6 . 31
63 Table 101 – Values of assumed loading . 16
64 Table 102 – Tightening torque values for the verification of mechanical strength . 17
65 Table AA.1 – Items subject to agreement between the DBO manufacturer and the user . 19
oSIST prEN IEC 61439-3:2022
IEC CDV 61439-3 © IEC 2022 4 121B/159/CDV

68 INTERNATIONAL ELECTROTECHNICAL COMMISSION
69 ____________
71 LOW-VOLTAGE SWITCHGEAR AND CONTROLGEAR ASSEMBLIES –
73 Part 3: Distribution boards intended to be operated
74 by ordinary persons (DBO)
76 FOREWORD
77 1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
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92 misinterpretation by any end user.
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105 8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
106 indispensable for the correct application of this publication.
107 9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of patent
108 rights. IEC shall not be held responsible for identifying any or all such patent rights.
109 International Standard IEC 61439-3 has been prepared by subcommittee 121B: Low-voltage
110 switchgear and controlgear assemblies, of IEC technical committee 121: Switchgear and
111 controlgear and their assemblies for low voltage.
112 This second edition cancels and replaces the first edition published in 2012, corrigendum 1
113 (2013) and corrigendum 2 (2019). It constitutes a technical revision.
114 This edition includes the following significant technical changes with respect to the previous
115 edition:
116 a) XX
117 b) XX
118 c) alignment with the structure of IEC 61439-1, 2020;
119 d) general editorial review.
120 The text of this standard is based on the following documents:
FDIS Report on voting
121B/XXX/FDIS 121B/XXX/RVD
...