IEC 61666:2010

IEC 61666 ®
Edition 2.0 2010-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
HORIZONTAL STANDARD
NORME HORIZONTALE
Industrial systems, installations and equipment and industrial products –
Identification of terminals within a system

Systèmes industriels, installations et appareils, et produits industriels –
Identification des bornes dans le cadre d’un système

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IEC 61666 ®
Edition 2.0 2010-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
HORIZONTAL STANDARD
NORME HORIZONTALE
Industrial systems, installations and equipment and industrial products –
Identification of terminals within a system

Systèmes industriels, installations et appareils, et produits industriels –
Identification des bornes dans le cadre d’un système

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 01.080.30 ISBN 978-2-88912-148-9
– 2 – 61666 © IEC:2010
CONTENTS
FOREWORD.3
1 Scope.5
2 Normative references .5
3 Terms and definitions .5
4 Terminal designation .7
4.1 General .7
4.2 Designation of terminals with respect to the product aspect.8
4.3 Designation of terminals with respect to the function aspect .9
4.4 Designation of terminals with respect to the location aspect .10
4.5 Terminal designation set .11
5 Classification of terminals.13
Annex A (informative) Examples of terminal designations not specified by a
manufacturer .14
Bibliography.16

Figure 1 – Principle of terminal designation .7
Figure 2 – Example of designation of terminals for a 3-phase squirrel-cage motor .9
Figure 3 – A device shown with function labels on which the terminal designations
related to the function aspect are based, as well as terminal designations (pins) related
to the product aspect .10
Figure 4 – Example of a symbol for a motor starter provided with terminal designations
related to the function aspect.10
Figure 5 – Example of a terminal board for cross-connection where the terminals are
designated related to their location aspect .11
Figure 6 – Example of a terminal designation set.12
Figure 7 – Example of a design with terminal designations related to the function
aspect.12
Figure 8 – Example of an implemented design based on Figure 7 with terminal
designations related to the product aspect.13
Figure 9 – Example of an implemented design based on Figure 7 with terminal
designation sets related to the function and product aspects .13
Figure A.1 – Four terminal blocks composing one terminal assembly (each terminal

block is considered as an object) .14
Figure A.2 – One terminal block with eight terminals (the complete unit is an object) .15
Figure A.3 – One terminal block with eight terminals with two entry points each .15

61666  IEC:2010 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
INDUSTRIAL SYSTEMS, INSTALLATIONS
AND EQUIPMENT AND INDUSTRIAL PRODUCTS –
IDENTIFICATION OF TERMINALS WITHIN A SYSTEM

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
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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 itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
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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 61666 has been prepared by IEC technical committee 3:
Information structures, documentation and graphical symbols
It has the status of a horizontal standard in accordance with IEC Guide 108.
This second edition cancels and replaces the first edition of IEC 61666 published in 1997.
This edition constitutes a technical revision.
This edition includes the following substantial changes with respect to the previous edition:
 the terminology used in the publication has been adapted to the one used in IEC 81346-1 Ed.2;
 a more comprehensive description of the designation principles is provided;
 additional examples illustrating terminal designations related to the function aspect and
location aspect are provided;
 an additional example illustrating the use of terminal designation sets is provided;
 the former informative Annex A has been turned into a clause in the standard.

– 4 – 61666 © IEC:2010
The text of this standard is based on the following documents:
FDIS Report on voting
3/1001/FDIS 3/1008/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.
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.
61666 © IEC:2010 – 5 –
INDUSTRIAL SYSTEMS, INSTALLATIONS
AND EQUIPMENT AND INDUSTRIAL PRODUCTS –
IDENTIFICATION OF TERMINALS WITHIN A SYSTEM

1 Scope
This International Standard establishes general principles for the identification of terminals of
objects within a system, applicable to all technical areas (for example mechanical
engineering, electrical engineering, construction engineering, process engineering). They can
be used for systems based on different technologies or for systems combining several
technologies.
Requirements for marking of terminal designations on products are not part of this publication.
NOTE The standard is based on the general principles for the structuring of systems including structuring of the
information about systems, established in the International Standard ISO/IEC 81346 series, published jointly by
IEC and ISO.
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 60445, Basic and safety principles for man-machine interface, marking and identification
– Identification of equipment terminals and conductor terminations
IEC 60757, Code for designation of colours
IEC 61082-1:2006, Preparation of documents used in electrotechnology – Part 1: Basic rules
IEC 81346-1, Industrial systems, installations and equipment and industrial products –
Structuring principles and reference designations – Part 1: Rules
IEC 81714-3, Design of graphical symbols for use in the technical documentation of products
– Part 3: Classification of connect nodes, networks and their encoding
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
object
entity treated in a process of development, implementation, usage and disposal
NOTE 1 The object may refer to a physical or non-physical “thing”, i.e. anything that might exist, exists or did
exist.
NOTE 2 The object has information associated to it.
[IEC 81346-1, definition 3.1]
– 6 – 61666 © IEC:2010
3.2
system
set of interrelated objects considered in a defined context as a whole and separated from their
environment
NOTE 1 A system is generally defined with the view of achieving a given objective, e.g. by performing a definite
function.
NOTE 2 Elements of a system may be natural or man-made material objects, as well as modes of thinking and the
results thereof (e.g. forms of organisation, mathematical methods, programming languages).
NOTE 3 The system is considered to be separated from the environment and from the other external systems by
an imaginary surface, which cuts the links between them and the system.
NOTE 4 The term “system” should be qualified when it is not clear from the context to what it refers, e.g. control
system, colorimetric system, system of units, transmission system.
NOTE 5 When a system is part of another system, it may be considered as an object as defined in this standard.
[IEV 151-11-27, modified]
3.3
aspect
specified way of viewing an object
[IEC 81346-1, definition 3.3]
3.4
function
intended or accomplished purpose or task
[IEC 81346-1, definition 3.5]
3.5
product
intended or accomplished result of labour, or of a natural or artificial process
[IEC 81346-1, definition 3.6]
3.6
component
product used as a constituent in an assembled product, system or plant
[IEC 81346-1, definition 3.7]
3.7
identifier
attribute associated with an object or system to unambiguously distinguish it from other
objects or systems within a specified domain
[IEC 81346-1, definition 3.10, modified]
3.8
reference designation
identifier of a specific object formed with respect to the system of which the object is a
constituent, based on one or more aspects of that system
[IEC 81346-1, definition 3.11]
3.9
terminal
point of access to an object intended for connection to an external network

61666 © IEC:2010 – 7 –
NOTE 1 The connection may refer to: a) a physical interface between conductors and/or contacts, or piping
and/or duct systems to provide a signal, energy or material flow path; b) an association of functional nature
established between logical elements, software modules, etc. for conveying information.
NOTE 2 The external networks may be of different nature and accordingly they may be classified. IEC 81714-3
provides such classifications.
3.10
terminal designation
identifier of a terminal with respect to the object to which it belongs, related to one defined
aspect
3.11
terminal designation set
group of terminal designations, each identifying the same terminal from different aspects
3.12
object designation
identifier of a specific object in a given context
NOTE Examples of such designations are: reference designation, type number, serial number, name.
[IEC 61355, 3.13]
4 Terminal designation
4.1 General
Terminals establish the interface of objects for connecting them to other objects in a network,
for example connecting to an electrical network, logic function network, logic network in
software, piping network, etc.
An object may be associated with any number of terminals.
Each terminal shall be unambiguously identified with respect to the object itself as well as to
the system to which this object belongs.
Figure 1 illustrates the principle of constructing an unambiguous terminal designation.
IEC  1956/10
Figure 1 – Principle of terminal designation

– 8 – 61666 © IEC:2010
The terminal designation shall consist of the terminal marking as defined by the manufacturer
or designer of the object used as component in the system or of the identifier as defined in
the documentation of the object.
If it is necessary to indicate the aspect of the terminal that the terminal designation relates to
(for example within human readable presentations), the terminal designation shall be
preceded by a prefix sign identifying the aspect.
NOTE 1 This prefix sign will exist in addition to the separator sign.
NOTE 2 The prefix sign is considered to be part of the terminal designation.
The terminal designation shall be formed according to 4.2, 4.3, or 4.4.
The terminal designation shall be presented, in documentation, in accordance with
IEC 61082-1.
The object designation shall unambiguously identify the object to which a terminal is
assigned. This implies that an object designation shall be (or be made) unambiguous in a
specified context, i. e. within the considered network.
NOTE 3 This requirement can be fulfilled by reference designations in accordance with IEC 81346-1 and such
designations are therefore used in the following text.
4.2 Designation of terminals with respect to the product aspect
A terminal designation provided with respect to the product aspect shall consist of the
designation of the physical terminal that is:
• marked on the product; or
• assigned by the manufacturer; or
• defined in relevant IEC publications; or
• known from convention.
Examples of the three last possibilities are a dual-in-line package or a contactor.
NOTE 1 Some product standards such as IEC 60034-8, IEC 60191-3 and IEC 60616 include requirements for
terminal markings of products.
If indication of the product aspect is needed in the terminal designation, the prefix sign “-“
shall be applied.
NOTE 2 The prefix sign is considered to be part of the terminal designation.
If there is no designation of the physical terminal assigned by the manufacturer of the
product, arbitrary terminal designations shall be assigned and shall be explained in the
document or in supporting documentation. The same applies also if the designation assigned
by the manufacturer is, for some reason, insufficient for unambiguous identification. See also
Annex A .
If the designation of the physical terminal has the form of a graphical symbol or colour, an
equivalent standardized letter symbol may be used in the documentation, for example, PE
instead of the graphical symbol for protective earth (see IEC 60445), BU for blue colour.
Letter codes for colours shall be in accordance with IEC 60757.
Figure 2 shows an example of designation of terminals for a motor.

61666 © IEC:2010 – 9 –
IEC  1957/10
Figure 2 – Example of designation of terminals for a 3-phase squirrel-cage motor
4.3 Designation of terminals with respect to the function aspect
A terminal designation provided with respect to the function aspect shall consist of a
designation based on the function(s) related to the terminal.
For functions of devices described by a data sheet or similar supporting document, a function
terminal designation should be based on the function label associated with terminal name
defined in the data sheet or the similar supporting document.
NOTE 1 Such terminal designations are for example defined in accordance with application note A00317 of
IEC 60617-S00317 (2001-07).
NOTE 2 Examples in IEC 60617 do not always provide labels that are unambiguous function terminal
designations. Whenever used as terminal designations, such labels need to be made unambiguous.
If indication of the function aspect is needed in the terminal designation, the prefix sign “=“
shall be applied.
NOTE 3 The prefix sign is considered to be part of the terminal designation.
Figure 3 shows an example of a device with function labels and terminal markings of the
terminals shown.
– 10 – 61666 © IEC:2010
RAM 16x4
A
Function label on which
1C2[WRITE]
Terminal designation the terminal designation
1EN[READ]
(2) related to the (G1) related to the
product aspect G1 function aspect is based
4 5
A, 2D
6 7
10 9
12 11
IEC  1958/10
Figure 3 – A device shown with function labels on which the terminal
designations related to the function aspect are based, as well as terminal
designations (pins) related to the product aspect
Figure 4 shows an example of a motor starter used as component with known functionality but
unknown physical implementation (i.e. the product to be used has not yet been selected). The
terminal designations are assigned from the function aspect by the designer of the complete
system in which such a motor starter may form part. These designations are used during the
system design and, during the detailed engineering, supplemented or replaced (by computer-
aided automatic means) by the terminal designations from the product aspect assigned by the
manufacturer of the product used for the implementation in each specific case.
NOTE 4 Clause 11 of IEC 61082-1 describes a mapping method for this.
IEC  1959/10
Figure 4 – Example of a symbol for a motor starter provided
with terminal designations related to the function aspect
4.4 Designation of terminals with respect to the location aspect
A terminal designation provided with respect to the location aspect shall consist of a
designation based on the location related to the terminal.
If the indication of the location aspect is needed in the terminal designation, the prefix sign “+“
shall be applied.
61666 © IEC:2010 – 11 –
NOTE 1 The prefix sign is considered to be part of the terminal designation.
The method used (e.g. a grid system) for location designation of terminals should be
explained in the document or in supporting documentation.
NOTE 2 Some methods for assigning location designations are provided in IEC 81346-1.
Figure 5 shows an example of a terminal board used for cross connection with a number of
terminals organized in a matrix where the rows along the x-axis are identified by letters and
the rows along the y-axis by numbers. Any terminal on the board can be identified by its xy
position.
IEC  1960/10
Figure 5 – Example of a terminal board for cross-connection
where the terminals are designated related to their location aspect

4.5 Terminal designation set
A terminal of an object can be associated with more than one terminal designation, and the
object to which the terminal belongs can at the same time be associated with a reference
designation set. This means that basically each member of the reference designation set can
be combined with each of the different terminal designations, each combination establishing
an identifying “terminal designation within a system”. If more than one of these terminal
designations needs to be indicated together, a terminal designation set shall be provided.
For a terminal designation set the following applies:
• each terminal designation shall be constructed according to the rules defined in 4.1, 4.2,
4.3, and 4.4;
• each terminal designation shall be clearly distinguishable from the others.
Figure 6 shows an example of a device with a terminal associated with a terminal designation
set.
Figure 7 shows an example of a design with terminal designations related to the function
aspect indicated.
Figure 8 shows an implementation of the same design, now with terminal designations related
to the product aspect indicated.
Figure 9 shows the implementation of the design with terminal designation sets indicated.

– 12 – 61666 © IEC:2010
=T1=K2
RAM 16x4
Terminal designation set:
A
=T1=K2:=1EN terminal designation related to the function aspect
=T1=K2:-3 terminal designation related to the product aspect
1C2[WRITE]
1EN[READ]
G1
4 5
A, 2D
6 7
10 9
12 11
IEC  1961/10
Figure 6 – Example of a terminal designation set

IEC  1962/10
Figure 7 – Example of a design with terminal designations related to the function aspect

61666 © IEC:2010 – 13 –
IEC  1962/10
Figure 8 – Example of an implemented design based on Figure 7 with terminal
designations related to the product aspect

IEC  1963/10
Figure 9 – Example of an implemented design based on Figure 7 with terminal
designation sets related to the function and product aspects
5 Classification of terminals
Products may be provided with multiple kinds of terminals designed for connection to different
kinds of networks, e.g. electrical, mechanical etc. These kinds of terminals shall be classified
according to IEC 81714-3. In such cases, where an object is equipped with different kinds of
terminals and presented in a common documentation, the accompanying documentation shall
clearly indicate what kind of terminal is provided. For this purpose the connect node code
given in IEC 81714-3 shall be used.

– 14 – 61666 © IEC:2010
Annex A
(informative)
Examples of terminal designations not specified by a manufacturer

Clause 4 specifies that a terminal designation shall be unambiguous with respect to the object
the terminal belongs to. For the correct interpretation of this statement, it is necessary to
consider what the object is in a specific case. When that is clarified, it is often experienced
that the marking provided by the manufacturer does not identify a terminal sufficiently for its
application in a system.
Objects designated by reference designations appear in parts lists; terminals of these objects
appear in connection tables. In circuit diagrams, the designated objects appear together with
their terminals.
The following provides some examples with identical functionality:
a) assembly composed of four terminal blocks; each containing two terminals, see
Figure A.1;
b) terminal block containing eight terminals, see Figure A.2;
c) terminal block containing 16 terminals, eight of which adapted to be connected to a
conductor with a larger cross-section, and eight of which adapted to be connected to a
conductor with a smaller cross-section, see Figure A.3.
Figure A.1 shows an example of a terminal assembly composed of four terminal blocks; each
terminal block has two terminals. In this case, the purchased terminal block often does not
include any designation of the terminals, but provides space where to mark the terminal block.
Normally, the terminal blocks are designated when the assembly is created. In such cases,
the terminal designations have to be assigned and described in the document or supporting
documentation. Possible conventions may be:
• 1 for one side, 2 for the other side, etc.;
• A for one side, B for the other side, etc.
Terminal
assembly
-X1
Terminal
Terminal
Terminals
1 23 4
block
Terminal
Spaceholder for
terminal marking
IEC  1964/10
Figure A.1 – Four terminal blocks composing one terminal assembly
(each terminal block is considered as an object)
In this case, each singular terminal block is considered as one object, designated –X1–1,
–X1–2, –X1–3 and –X1–4. Consequently, the identification of the terminals may be –X1–1:1,
–X1–1:2, etc, or –X1–1:A, –X1–1:B, etc.
Note that it is also possible to handle the terminal designation of the ”on-site” constructed
terminal assembly shown in Figure A.1 in the same way as indicated in Figure A.2 if the
terminal assembly is considered as the referenced designated object in the documentation.

61666 © IEC:2010 – 15 –
Figure A.2 shows an example of a terminal block containing eight terminals. In this case the
purchased terminal block includes markings according to Figure A.2 a) or Figure A.2 b). The
complete unit is considered as the object that is reference designated –X1.

Figure A.2 – One terminal block with eight terminals
(the complete unit is an object)
In the case of Figure A.2 a), the markings provided do not sufficiently identify each terminal,
and terminal designations have to be assigned and described in the document or in
supporting documentation. Possible conventions may be, using the character FULL STOP ( . )
as a separator sign behind the markings on the product:
• 1 for one side, 2 for the other side, etc.;
• A for one side, B for the other side, etc.
Consequently, the identification of the terminals are –X1:1.1, –X1:1.2, etc, or –X1:1.A,
–X1:1.B, etc.
In the case of Figure A.2 b), the terminals are sufficiently marked and shall be used as they
are. The identification of the terminals are –X1:11, –X1:12, –X1:21, –X1:22, etc.
Figure A.3 shows an example of a terminal block containing eight terminals, each of which is
adapted to be connected to a conductor with a larger cross-section, and also to be connected
to a conductor with a smaller cross-section. This creates a total of 16 entry points for
conductors that must be provided with designations so they can be distinguished from one
another.
IEC  1965/10 IEC  1966/10
Figure A.3 – One terminal block with eight terminals with two entry points each
In this case, the terminal designations have to be assigned and described in the document or
in supporting documentation. Possible conventions for designating multiple entry points on
one terminal may be, using the character FULL STOP ( . ) as a separator sign behind the
markings on the product:
• 1, 2, 3, etc.;
• A, B, C, etc.
Consequently, the identification of the terminals are –X1:11.1, –X1:11.2, etc, or –X1:11.A,
–X1:11.B, etc.
– 16 – 61666 © IEC:2010
Bibliography
IEC 60034-8:2007, Rotating electrical machines – Part 8: Terminal markings and direction of
rotation
IEC 60050-151, International Electrotechnical Vocabulary – Part 151: Electrical and magnetic
devices
IEC 60191-3:1999, Mechanical standardization of semiconductor devices – Part 3: General
rules for the preparation of outline drawings of integrated circuits
IEC/TR 60616:1978, Terminal and tapping markings for power transformers
IEC 60617, Graphical symbols for diagrams
IEC 61355, Classification and designation of documents for plants, systems and equipment –
Part 1: Rules and classification tables

___________
– 18 – 61666 © CEI:2010
SOMMAIRE
AVANT-PROPOS.19
1 Domaine d’application .21
2 Références normatives.21
3 Termes et définitions .21
4 Désignation de borne .23
4.1 Généralités.23
4.2 Désignation de bornes par rapport à l’aspect de produit .24
4.3 Désignation de bornes par rapport à l’aspect de fonction.25
4.4 Désignation des bornes par rapport à l’aspect emplacement .26
4.5 Ensemble de désignations de bornes .27
5 Classification des bornes.29
Annexe A (informative) Exemples de désignations de bornes non spécifiées par un
fabricant .30
Bibliographie.32

Figure 1 – Principe de désignation de borne .24
Figure 2 – Exemple de désignation de bornes pour un moteur triphasé à cage
d’écureuil.25
Figure 3 – Dispositif comportant des repères de fonction sur lesquels sont fondées les
désignations de borne liées à l’aspect de fonction, ainsi que les désignations de borne
(broches) liées à l’aspect de produit .26
Figure 4 – Exemple de symbole pour démarreur de moteur muni de désignations de
borne liées de l’aspect fonction.26
Figure 5 – Exemple de plaque à bornes en vue d’une interconnexion où les bornes
sont désignées en relation avec leur aspect emplacement .27
Figure 6 – Exemple d’ensemble de désignations de bornes .28
Figure 7 – Exemple de conception comportant des désignations de bornes liées à
l’aspect de fonction.28
Figure 8 – Exemple de mise en œuvre de conception fondée sur la Figure 7
comportant des désignations de bornes liées à l’aspect de produit .29
Figure 9 – Exemple de mise en œuvre de conception fondée sur la Figure 7
comportant des ensembles de désignations de bornes liées aux aspects de fonction et
de produit .29
Figure A.1 – Quatre borniers composant un ensemble de connexion (chaque bornier
est considéré comme un objet) .30
Figure A.2 – Un bornier comportant huit bornes (l'unité entière constitue un objet) .31
Figure A.3 – Un bornier comportant huit bornes avec chacune deux points d’entrée .31

61666  CEI:2010 – 19 –
COMMISSION ÉLECTROTECHNIQUE INTERNATIONALE
____________
SYSTÈMES INDUSTRIELS, INSTALLATIONS
ET APPAREILS, ET PRODUITS INDUSTRIELS –
IDENTIFICATION DES BORNES DANS LE CADRE D’UN SYSTÈME

AVANT-PROPOS
1) La Commission Electrotechnique Internationale (CEI) est une organisation mondiale de normalisation
composée de l'ensemble des comités électrotechniques nationaux (Comités nationaux de la CEI). La CEI a
pour objet de favoriser la coopération internationale pour toutes les questions de normalisation dans les
domaines de l'électricité et de l'électronique. A cet effet, la CEI – entre autres activités – publie des Normes
internationales, des Spécifications techniques, des Rapports techniques, des Spécifications accessibles au
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organisations internationales, gouvernementales et non gouvernementales, en liaison avec la CEI, participent
également aux travaux. La CEI collabore étroitement avec l'Organisation Internationale de Normalisation (ISO),
selon des conditions fixées par accord entre les deux organisations.
2) Les décisions ou accords officiels de la CEI concernant les questions techniques représentent, dans la mesure
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intéressés sont représentés dans chaque comité d’études.
3) Les Publications de la CEI se présentent sous la forme de recommandations internationales et sont agréées
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de l'éventuelle mauvaise utilisation ou interprétation qui en est faite par un quelconque utilisateur final.
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toute autre Publication de la CEI, ou au crédit qui lui est accordé.
8) L'attention est attirée sur les références normatives citées dans cette publication. L'utilisation de publications
référencées est obligatoire pour une application correcte de la présente publication.
9) L’attention est attirée sur le fait que certains des éléments de la présente Publication de la CEI peuvent faire
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responsable de ne pas avoir identifié de tels droits de propriété et de ne pas avoir signalé leur existence.
La Norme internationale CEI 61666 a été établie par le comité d’études 3 de la CEI:
Structures d'information, documentation et symboles graphiques.
Elle a le statut d’une norme horizontale conformément au Guide 108 de la CEI.
Cette deuxième édition annule et remplace la première édition publiée en 1997. Cette édition
constitue une révision technique.
Cette édition inclut les modifications substantielles suivantes par rapport à l'édition précédente:
 la terminologie utilisée dans la publication a été adaptée à celle utilisée dans la CEI
81346-1 Ed. 2;
 une description plus complète des principes de désignation est fournie;
 des exemples additionnels illustrant des désignations de bornes se rapportant à l'aspect
de fonction et l'aspect d'emplacement sont fournis;

– 20 – 61666 © CEI:2010
• un exemple additionnel illustrant l'utilisation des ensembles de désignation de bornes est
fourni;
• l'ancienne Annexe A (informative) a été transformée en un article de la norme.
Le texte de cette norme est issu des documents suivants:
FDIS Rapport de vote
3/1001/FDIS 3/1008/RVD
Le rapport de vote indiqué dans le tableau ci-dessus donne toute information sur le vote ayant
abouti à l'approbation de cette norme.
Cette publication a été rédigée conformément aux spécifications des Directives ISO/CEI,
Partie 2.
Le comité a décidé que le contenu de cette publication ne sera pas modifié avant la date de
stabilité indiquée sur le site web de la CEI sous "http://webstore.iec.ch" dans les données
r
...