IEC 60757:2021

Code for designation of colours

IEC 60757:2021 specifies letter codes for designation of colours and provides rules for their combination to designate colour combinations. The letter codes are intended to be applied in the technical documentation of electrical installations, electrical equipment and products, and in markings of electrical equipment and products.
This basic safety publication focusing on safety essential requirements is primarily intended for use by technical committees in the preparation of safety publications in accordance with the principles laid down in IEC Guide 104 and ISO/IEC Guide 51.
It is not intended for use by manufacturers or certification bodies. One of the responsibilities of a technical committee is, wherever applicable, to make use of basic safety publications in the preparation of its publications. The requirements of this basic safety publication will not apply unless specifically referred to or included in the relevant publications.
This document does not specify any requirements for the encoding of colour properties, nor for their visual representation. Such requirements are under the responsibility of the different technical committees.
IEC 60757:2021 cancels and replaces the first edition published in 1983. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous edition:
a) codes restricted to letter codes;
b) removed old unnecessary notes;
c) added a new subclause on alternating colours of the same item;
d) added Annex A with examples of colours and their corresponding RGB (red, green, blue) encoding.

Code de désignation de couleurs

L'IEC 60757:2021 spécifie les codes littéraux de désignation de couleurs et donne des règles régissant leur combinaison, afin de désigner les combinaisons de couleurs. Les codes littéraux sont destinés à être appliqués dans la documentation technique des installations électriques, des équipements et produits électriques, ainsi que dans les marquages des équipements et produits électriques.
La présente publication fondamentale de sécurité portant sur des exigences essentielles de sécurité est avant tout destinée à être utilisée par les comités d’études dans le cadre de l’élaboration de publications de sécurité, conformément aux principes établis dans le Guide IEC 104 et le Guide lSO/lEC 51.
Elle n’est pas destinée à être utilisée par les fabricants ou les organismes de certification. L’une des responsabilités d’un comité d’études consiste, le cas échéant, à utiliser les publications fondamentales de sécurité dans le cadre de l’élaboration de ses publications. Les exigences de la présente publication fondamentale de sécurité ne s’appliquent pas tant qu’il n’y a pas été fait spécifiquement référence ou qu’elles n’ont pas été incluses dans les publications concernées.
Le présent document ne spécifie pas d’exigences relatives au codage des propriétés des couleurs, ni à leur représentation visuelle. De telles exigences relèvent de la responsabilité des différents comités d’études.
L'IEC 60757:2021 annule et remplace la première édition parue en 1983. Cette édition constitue une révision technique.
Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:
a) restriction des codes à des codes littéraux;
b) suppression des anciennes notes superflues;
c) ajout d’un paragraphe sur un élément utilisant différentes couleurs par alternance;
d) ajout de l'0 avec des exemples de couleurs et leur codage RVB (rouge, vert, bleu) correspondant.

General Information

• Status: Published
• Publication Date: 15-Jun-2021
• ICS: 01.070 - Colour coding
• ICS: 29.020 - Electrical engineering in general
• Technical Committee: TC 3 - Documentation, graphical symbols and representations of technical information
• Drafting Committee: MT 23 - TC 3/MT 23
• Current Stage: PPUB - Publication issued
• Start Date: 02-Jul-2021
• Completion Date: 16-Jun-2021

Standards Content (Sample)

IEC 60757 ®
Edition 2.0 2021-06
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
BASIC SAFETY PUBLICATION
PUBLICATION FONDAMENTALE DE SÉCURITÉ
Code for designation of colours

Code de désignation de couleurs

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IEC 60757 ®
Edition 2.0 2021-06
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
BASIC SAFETY PUBLICATION
PUBLICATION FONDAMENTALE DE SÉCURITÉ

Code for designation of colours

Code de désignation de couleurs

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 01.070; 29.020 ISBN 978-2-8322-9881-7

– 2 – IEC 60757:2021 © IEC 2021
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 Letter codes for colours . 5
5 Application of colour designations . 6
5.1 Multiple colours on the same item . 6
5.2 Alternating colours of the same item . 6
5.3 Colours on different subitems of an item . 6
Annex A (informative) Examples of colours . 7

Table 1 – Colours and their letter code . 6
Table A.1 – Examples of the colours and their RGB encoding . 7

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
CODE FOR DESIGNATION OF COLOURS

FOREWORD
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rights. IEC shall not be held responsible for identifying any or all such patent rights.
IEC 60757 has been prepared by IEC technical committee 3: Documentation, graphical symbols
and representations of technical information. It is an International Standard.
It has the status of a basic safety publication in accordance with IEC Guide 104.
This second edition cancels and replaces the first edition published in 1983. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) codes restricted to letter codes;
b) removed old unnecessary notes;
c) added a new subclause on alternating colours of the same item;
d) added Annex A with examples of colours and their corresponding RGB (red, green, blue)
encoding.
– 4 – IEC 60757:2021 © IEC 2021
The text of this International Standard is based on the following documents:
FDIS Report on voting
3/1486/FDIS 3/1513/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
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• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct understanding
of its contents. Users should therefore print this document using a colour printer.

CODE FOR DESIGNATION OF COLOURS

1 Scope
This document specifies letter codes for designation of colours and provides rules for their
combination to designate colour combinations. The letter codes are intended to be applied in
the technical documentation of electrical installations, electrical equipment and products, and
in markings of electrical equipment and products.
This basic safety publication focusing on safety essential requirements is primarily intended for
use by technical committees in the preparation of safety publications in accordance with the
principles laid down in IEC Guide 104 and ISO/IEC Guide 51.
It is not intended for use by manufacturers or certification bodies. One of the responsibilities of
a technical committee is, wherever applicable, to make use of basic safety publications in the
preparation of its publications. The requirements of this basic safety publication will not apply
unless specifically referred to or included in the relevant publications.
This document does not specify any requirements for the encoding of colour properties, nor for
their visual representation. Such requirements are under the responsibility of the different
technical committees.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies.
For undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 60445, Basic and safety principles for man-machine interface, marking and identification –
Identification of equipment terminals, conductor terminations and conductors
3 Terms and definitions
No terms and definitions are listed in this document.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO
...