IEC 60445:2006

INTERNATIONAL IEC
STANDARD 60445
Fourth edition
2006-11
BASIC SAFETY PUBLICATION
Basic and safety principles for man-machine
interface, marking and identification –
Identification of equipment terminals and
conductor terminations
Reference number
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INTERNATIONAL IEC
STANDARD 60445
Fourth edition
2006-11
BASIC SAFETY PUBLICATION
Basic and safety principles for man-machine
interface, marking and identification –
Identification of equipment terminals and
conductor terminations
© IEC 2006 ⎯ Copyright - all rights reserved
No part of this publication may be reproduced or utilized in any form or by any means, electronic or
mechanical, including photocopying and microfilm, without permission in writing from the publisher.
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Telephone: +41 22 919 02 11 Telefax: +41 22 919 03 00 E-mail: inmail@iec.ch Web: www.iec.ch
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For price, see current catalogue

– 2 – 60445 © IEC:2006(E)
CONTENTS
FOREWORD.3

INTRODUCTION.5

1 Scope.6

2 Normative references .6

3 Terms and definitions .6

4 Methods of identification.8

5 Application of identification means .8
6 General rules for an alphanumeric system.8
6.1 General .8
6.2 Marking principles .8
7 Marking of equipment terminals intended for certain designated conductors and of
terminations of these conductors .11

Bibliography.13

Figure 1 – Single element with two terminals .9
Figure 2 – Single element with four terminals: two endpoints and two intermediate
points .9
Figure 3 – Three-phase equipment with six terminals.9
Figure 4 – Three-element equipment with twelve terminals: six endpoints and six
intermediate points .10
Figure 5a – Three-phase equipment with two groups of elements .10
Figure 5b – Two-phase equipment with two groups of elements with four terminals
each .10
Figure 5 – Equipment with groups of elements.10
Figure 6 – Interconnection of equipment terminals and certain designated conductors.11

Table 1 – Marking of equipment terminals intended for certain designated conductors.12

60445 © IEC:2006(E) – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION

____________
BASIC AND SAFETY PRINCIPLES FOR MAN-MACHINE INTERFACE,

MARKING AND IDENTIFICATION –
IDENTIFICATION OF EQUIPMENT TERMINALS AND CONDUCTOR

TERMINATIONS
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,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
in the subject dealt with may participate in this preparatory work. International, governmental and non-
governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with an IEC Publication.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
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 60445 has been prepared by IEC technical committee 16: Basic
and safety principles for man-machine interface, marking and identification.
This fourth edition cancels and replaces the third edition published in 1999 and constitutes a
technical revision. This edition includes the following significant technical changes with
respect to the previous edition:
a) addition of Table 1 – Protective bonding conductor PB (earthed PBE, unearthed PBU);
b) addition of footnotes e and f in Table 1 indicating "UK special national conditions";
c) deletion of Annex A (informative): "Comparison of former and present designation".
It has the status of a basic safety publication in accordance with IEC Guide 104.

– 4 – 60445 © IEC:2006(E)
The text of this standard is based on the following documents:

FDIS Report on voting
16/458/FDIS 16/460/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 publication has been drafted in accordance with the ISO/IEC Directives, Part 2.

Table 1 of this standard includes UK special national conditions.
The committee has decided that the contents of this publication will remain unchanged until

the maintenance result 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.
A bilingual version of this publication may be issued at a later date.

60445 © IEC:2006(E) – 5 –
INTRODUCTION
This basic safety publication is intended for use by technical committees in the preparation

of standards in accordance with the principles laid down in IEC Guide 104 and in ISO/IEC

Guide 51.
It should be noted that one of the responsibilities of a technical committee is, wherever

possible, to include or refer to requirements of basic safety publications in standards for

equipment within its scope. Consequently, the requirements of this basic safety publication

apply only if they are included, or are referred to in those standards.

In this fourth edition of IEC 60445, the terminology has been aligned with IEC 60050-195.

– 6 – 60445 © IEC:2006(E)
BASIC AND SAFETY PRINCIPLES FOR MAN-MACHINE INTERFACE,

MARKING AND IDENTIFICATION –
IDENTIFICATION OF EQUIPMENT TERMINALS AND CONDUCTOR

TERMINATIONS
1 Scope
This International Standard applies to the identification and marking of terminals of electrical
equipment such as resistors, fuses, relays, contactors, transformers, rotating machines and,
wherever applicable, to combinations of such equipment (e.g. assemblies). It also applies to
the identification of terminations of certain designated conductors. This standard further
includes general rules for an alphanumeric system.
2 Normative references
The following referenced documents are indispensable for the application 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 60417, Graphical symbols for use on equipment
IEC 60446, Basic and safety principles for man-machine interface, marking and identification
– Identification of conductors by colours or numerals
IEC 60617, Graphical symbols for diagrams
IEC Guide 104, The preparation of safety publications and the use of basic safety publications
and group safety publications
ISO/IEC Guide 51, Safety aspects – Guidelines for their inclusion in standards
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.

NOTE The terms are sorted in alphabetical order.
3.1
functional bonding conductor
conductor provided for functional-equipotential-bonding
[IEV 195-02-16]
3.2
functional earthing conductor
functional grounding conductor (in US)
earthing conductor provided for functional earthing
[IEV 195-02-15]
60445 © IEC:2006(E) – 7 –
3.3
line conductor
phase conductor (in AC systems) (deprecated)

pole conductor (in DC systems) (deprecated)

conductor which is energized in normal operation and capable of contributing to the

transmission or distribution of electric energy but which is not a neutral or mid-point conductor

[IEV 195-02-08]
3.4
mid-point conductor
conductor electrically connected to the mid-point and capable of contributing to the
distribution of electric energy
[IEV 195-02-07]
3.5
neutral conductor
conductor electrically connected to the neutral point and capable of contributing to the
distribution of electric energy
[IEV 195-02-06]
3.6
PEL conductor
conductor combining the functions of both a protective earthing conductor and a line
conductor
[IEV 195-02-14]
3.7
PEM conductor
conductor combining the functions of both a protective earthing conducto
...