IEC 62491:2008

IEC 62491
Edition 1.0 2008-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Industrial systems, installations and equipment and industrial products –
Labelling of cables and cores
Systèmes industriels, installations et appareils et produits industriels –
Etiquetage des câbles et des conducteurs isolés

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IEC 62491
Edition 1.0 2008-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Industrial systems, installations and equipment and industrial products –
Labelling of cables and cores
Systèmes industriels, installations et appareils et produits industriels –
Etiquetage des câbles et des conducteurs isolés

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX U
ICS 01.110; 29.020.20 ISBN 2-8318-9663-0

– 2 – 62491 © IEC:2008
CONTENTS
FOREWORD.4
INTRODUCTION.6
1 Scope.7
2 Normative references .7
3 Terms and definitions .8
4 Rules.9
4.1 General requirements.9
4.2 Use of designated cable cores.10
4.3 Use of additional labelling .10
5 Identification labelling.11
5.1 General .11
6 Connection labelling .14
6.1 General .14
6.2 Local-end connection labelling .14
6.3 Remote-end connection labelling.15
6.4 Both-end connection labelling.16
7 Signal labelling.17
7.1 General .17
7.2 Labelling by signal designation.17
7.3 Labelling of cables for certain designated conductors.18
8 Composite labelling .19
9 Arrangement of additional labelling.20
9.1 General .20
9.2 Relative positions of the labelling .20
9.3 Characters to be used .20
10 Correspondence between labelling and documentation.21
11 Conformance to this standard.21
Annex A (informative) Examples of labelling .22
Bibliography.30

Figure 1 – Example of identification labelling of a single core cable (W23) and of a
multi-core cable (W24) in which also the different cores are labelled .12
Figure 2 – Example of identification labelling of cores where the initial part of the
reference designation has been partly omitted .13
Figure 3 – Example of local-end connection labelling.14
Figure 4 – Example of remote-end connection labelling for a connection inside a unit.15
Figure 5 – Example of remote-end connection labelling for a cable between different
units .16
Figure 6 – Example of both-end connection labelling .17
Figure 7 – Example of local-end connection labelling combined with signal labelling.19
Figure 8 – Example of composite labelling in which both-end connection labelling is
used together with identification labelling and signal labelling.19
Figure 9 – Examples of arrangements of labelling on cores or cables. .20
Figure A.1 – Circuit diagram used as a basis for the examples .22

62491 © IEC:2008 – 3 –
Figure A.2 – Example of identification labelling .23
Figure A.3 – Example of local-end labelling .24
Figure A.4 – Example of both-end connection labelling .25
Figure A.5 – Example of local end connection labelling with additional information .26
Figure A.6 – Example of signal labelling .27
Figure A.7 – Example of composite labelling.28
Figure A.8 – Example where use is made of the cable colours .29

Table 1 – Example of connection table in which the cable cores are identified by
means of codes for their colour.10
Table 2 – Connection table corresponding to Figure 1 with labelling .12
Table 3 – Connection table corresponding to Figure 2 with labelling .13
Table 4 – Marking of certain designated conductors.18
Table 5 – Methods of labelling defined in this standard .21

– 4 – 62491 © IEC:2008
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
INDUSTRIAL SYSTEMS, INSTALLATIONS
AND EQUIPMENT AND INDUSTRIAL PRODUCTS –
LABELLING OF CABLES AND CORES
FOREWORD
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