IEC TS 62666:2016

IEC TS 62666 ®
Edition 2.0 2016-08
TECHNICAL
SPECIFICATION
Guidelines for the inclusion of documentation aspects in product standards
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IEC TS 62666 ®
Edition 2.0 2016-08
TECHNICAL
SPECIFICATION
Guidelines for the inclusion of documentation aspects in product standards

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 01.110 ISBN 978-2-8322-3569-0

– 2 – IEC TS 62666:2016 © IEC 2016
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative references. 6
3 Terms and definitions . 6
4 Principal guidelines . 9
4.1 Adaptation to the needs for the system or product . 9
4.2 Adaptation to the structure of the publication . 9
5 Requirements to be covered . 10
5.1 Information requirements . 10
5.2 Documentation requirements . 11
5.2.1 General . 11
5.2.2 Structuring of the documentation . 12
5.2.3 Identification and classification . 13
5.2.4 Document kinds, their purpose and preparation . 15
5.2.5 Graphical symbols . 15
5.2.6 Characteristic properties and data element types . 16
5.3 Requirements on documentation generated by tools other than CAx tools . 17
Annex A (informative) Example of a clause specifying documentation requirements
for a complex system or product . 18
A.1 Technical documentation . 18
A.2 Information to be provided . 18
A.3 Requirements for documents and documentation . 19
A.3.1 General requirements . 19
A.3.2 Main document . 19
A.3.3 Labelling . 20
A.4 Specific requirements for certain kinds of information . 20
A.4.1 Information on installation and mounting . 20
A.4.2 Information on factory and site testing . 20
A.4.3 Information on function and operation . 20
A.4.4 Information on maintenance . 20
A.4.5 Information on disassembly, recycling and disposal . 20
Annex B (informative) Example of a clause specifying documentation requirements for
a simple (consumer) product . 21
B.1 Technical documentation . 21
B.2 Information to be provided . 21
B.3 Requirements for documents and documentation . 22
B.3.1 General requirements . 22
B.3.2 Labelling . 22
B.3.3 Specific requirements for some kinds of information . 22
Bibliography . 24

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
GUIDELINES FOR THE INCLUSION OF DOCUMENTATION
ASPECTS IN PRODUCT STANDARDS
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 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.
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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.
The main task of IEC technical committees is to prepare International Standards. In
exceptional circumstances, a technical committee may propose the publication of a technical
specification when
• the required support cannot be obtained for the publication of an International Standard,
despite repeated efforts, or
• the subject is still under technical development or where, for any other reason, there is the
future but no immediate possibility of an agreement on an International Standard.
Technical specifications are subject to review within three years of publication to decide
whether they can be transformed into International Standards.
IEC 62666, which is a technical specification, has been prepared by IEC technical
committee 3: Information structures and elements, identification and marking principles,
documentation and graphical symbols.
This second edition cancels and replaces the first edition published in 2010. This edition
constitutes a technical revision.

– 4 – IEC TS 62666:2016 © IEC 2016
This edition includes the following significant technical changes with respect to the previous
edition:
a) the references to relevant standards have been updated and horizontal standards have
been designated;
b) a new subclause "Identification of equipment, basic and safety principles" has been
added. The reason for this is that a group of standards have been placed under the
responsibility of TC 3.
The text of this technical specification is based on the following documents:
Enquiry draft Report on voting
3/1256/DTS 3/1261/RVC
Full information on the voting for the approval of this technical specification 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 website under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• transformed into an International standard,
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
A bilingual version of this publication may be issued at a later date.

INTRODUCTION
This Technical Specification is developed in response to expressed needs for guidelines on
requirements for documentation in product and system standards.
This document is written for the target group Product Committee Secretaries, PT- and
MT-members, etc. It provides some basic information on documentation principles,
explanations and justifications to why the references to documentation standards should be
made. It is assumed that experts developing product standards have not necessarily relevant
documentation aspects as their primary interest. As a consequence, the text may by some be
found too “educational” for a standard. In a guideline it may, however, be more appropriate.
The two annexes are examples intended to be used as templates for how texts should be
included in product standards.

– 6 – IEC TS 62666:2016 © IEC 2016
GUIDELINES FOR THE INCLUSION OF DOCUMENTATION
ASPECTS IN PRODUCT STANDARDS
1 Scope
This Technical Specification provides guidelines to ensure consistency with respect to the
specification of requirements for information, documentation and graphical symbols in IEC
publications provided by system or product committees.
NOTE 1 Guidelines regarding inclusion of graphical symbols on equipment are presented in IEC 62648.
NOTE 2 This Technical Specification is based on and fully customizes IEC Guide 108.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
NOTE 1 An alphabetical index including all terms is contained at the end of this document.
NOTE 2 Definitions taken over from other International Standards are not necessarily literally cited, but adapted
to the form required for terms and definitions according to the ISO/IEC Directives.
3.1
knowledge
body of understanding and skills
Note 1 to entry: The “body of understanding” can e.g. consist of facts, concepts and instructions.
3.2
information
knowledge (see 3.1) that is communicated
3.3
data
representation of information (see 3.2) in a formalized manner suitable for communication,
interpretation or processing
Note 1 to entry: Data can be processed by humans or by electronic means.
3.4
data carrier
material on which data (see 3.3) can be stored
3.5
medium
means of representing data (see 3.3) on a data carrier (see 3.4)

3.6
data element type
DET
unit of data (see 3.3) for which the identification, description and value representation have
been specified
[SOURCE: IEC 61360-1:2009, 2.3]
3.7
document
fixed and structured amount of information (see 3.2) that can be managed and interchanged
as a unit between users and systems
Note 1 to entry: This unit may not necessarily be human perceptible. Information (see 3.2) is usually stored as
data on a data medium (see 3.5).
Note 2 to entry: “users” refers in this definition to users of information (see 3.2) and “systems” refers to systems
managing information and documentation (see 3.10).
[SOURCE: IEC 82045-1:2001, 3.2.3, modified – Note 1 has been slightly changed and Note 2
has been added.]
3.8
document kind
type of document (see 3.7) defined with respect to its specified content of information (see
3.2) and form of presentation
[SOURCE: IEC 61355-1:2008, 3.6]
3.9
document set
collection of documents (see 3.7) that are managed together as a unit for a specific purpose
Note 1 to entry: Document sets may consist of documents (see 3.7) and composite documents.
[SOURCE: IEC 61355-1:2008, 3.4, modified – The definition has been slightly changed.]
3.10
documentation
collection of documents (see 3.7) related to a given subject
Note 1 to entry: This can include technical, commercial and other documents (see 3.7).
Note 2 to entry: The term may refer to objects in the sense of IEC 81346 series or to other things to be
addressed.
Note 3 to entry: A documentation can consist of documents, composite documents and document sets.
Note 4 to entry: The number and kinds of documents in a documentation can differ according to purpose.
[SOURCE: IEC 61355-1:2008, 3.5]
3.11
domain
distinguished part of an abstract or physical space where something exists
Note 1 to entry: A domain can be e.g. an organization or a country or a part of it.
[SOURCE: IEC 62507-1:2010, 3.2]

– 8 – IEC TS 62666:2016 © IEC 2016
3.12
object
entity treated in a process of development, implementation, usage and disposal
Note 1 to entry: The object may refer to a physical or non-physical “thing”, i.e. anything that might exist, exists or
did exist.
Note 2 to entry: The object has information (see 3.2) associated to it.
[SOURCE: IEC 81346-1:2009, 3.1]
3.13
characteristic property
defined parameter suitable for the description and differentiation of objects (see 3.12)
[SOURCE: IEC PAS 62569-1:2009, 3.1.6, modified – "Characteristic" has been added to
"property" and the note has been deleted.]
3.14
identifier
attribute associated with an object (see 3.12) to unambiguously identify it in a specified
domain (see 3.11)
Note 1 to entry: In an identification system several types of identifiers may be required.
[SOURCE: IEC 62507-1:2010, 3.8]
3.15
identification number
ID
string of characters representing the value of the identifier (see 3.14)
Note 1 to entry: It is practice that although the term says “number” the string can contain other types of
characters as well.
Note 2 to entry: Note that the term “identifier” (see 3.14) as being an attribute and the term ”identification number”
as being the value of that attribute are here considered different things, but they are often mixed in existing
definitions.
Note 3 to entry: Identification numbers are often required to be unique (an object (see 3.12) shall have one
number only). This is an unnecessary strong requirement, it is sufficient if they are unambiguous within a specified
domain. An object may have more than one identification number.
Furthermore, it is assumed in the definition that an organization may be responsible for more than one
identification number domain. This is a commonly occurring situation when organizations are merged, etc.
[SOURCE: IEC 62507-1:2010, 3.5]
3.16
horizontal standard
standard on fundamental principles, concepts, terminology or technical characteristics,
relevant to a number of technical committees and of crucial importance to ensure the
coherence of the corpus of standardization documents
[SOURCE: IEC Guide 108:2006, 3.1]
3.17
product publication
publication covering a specific product or group of related products
Note 1 to entry: In this document, the term product includes items such as process, service, installation and
combinations thereof, commonly known as systems.

Note 2 to entry: “product publication” refers in this document to publications issued by IEC. The same term is
sometimes used by product manufacturers with a different meaning.
[SOURCE: IEC Guide 108:2006, 3.2, modified – Note 2 has been added.]
3.18
commissioning
procedures prior, or related, to the handing over of a product ready for putting into service,
including final acceptance testing, the handing over of all documentation relevant to the use
of the product and, if necessary, instructing personnel
[SOURCE: IEC 82079-1:2012, 3.3]
4 Principal guidelines
4.1 Adaptation to the needs for the system or product
Documentation is a result of development and engineering of a system or a product. Its major
purpose is to enable the system or product to be manufactured and supplied to users for
intended use.
The provision of information in the form of documentation is an integral part of any delivery of
system or a product and one purpose is to transfer knowledge of the system or product from
the supplier to the user.
The documents accompanying the system or the product are a subset of the total number of
documents on it. Documents for manufacturing and results of testing are examples on other
documents. The information accompanying the system or the product should promote correct
and safe application and use of the system or product for the remaining part of its life cycle.
Product standards should therefore specify required
• information, and
• documentation.
The primary requirement is on the information needs and the structuring of this information so
that required information can be easily accessed by users.
A secondary requirement is how this information is “packaged” and presented in the form of a
logically related collection of documents, i.e. the documentation for the system or product on
relevant media.
The requirements on the documentation and the amount of documents needed depend on the
complexity of the system or product as well as of the intended use and foreseen users and
may vary. The specified requirements in the system or product standard should therefore be
adapted to the needs in the actual case.
4.2 Adaptation to the structure of the publication
In a product publication, the requirements on information and documentation should
preferably be collected in one clause with subclauses for information and documentation
requirements respectively.
The requirements should be included by referencing to the relevant specialized
documentation standards where available, in order to keep the content of the references up-
to-date with actual developments of these standards.

– 10 – IEC TS 62666:2016 © IEC 2016
For the sake of understanding and promotion, the referencing should not only be made by
listing standard identification numbers of such standards but should also include some
introductory information that explains and justifies each reference.
If there are special documentation requirements not yet covered by existing standards, these
should be incorporated as text in the system or product standard. In such cases, relevant IEC
or ISO committees should also be informed about the missing information for due
consideration when existing standards are revised or in order to develop new ones.
Note that before making such a proposal, consideration should be given to the fact that the
terminology used in the documentation standards, for example names of document types, may
be different compared to the terminology used among experts in the product committee. The
database IEC 61355 (http://std.iec.ch/iec61355) contains the recommended terminology, but
also a number of synonyms, and suggestions on how to deal with them.
Clause 5 provides information on the requirements covered in available documentation
standards. The purpose of this clause is to make readers aware of the content in order to
decide whether or not the requirements are relevant for the actual product publication.
Annex A is intended as a template for a clause for “Technical documentation” in a product
standard for a comprehensive system or equipment (for example industrial plant or
installation), which requires comprehensive documentation. The product may in this case also
be expected to be modified by the user during its remaining life time and its documentation
therefore to be updated and maintained by the user. The number of needed technical
documents can in this case be high.
Annex B is intended as a template for a clause for “Technical documentation” in a product
standard for a relatively simple (from a user perspective) consumer product that requires a
simple installation or no installation at all. The supplied documentation is not intended to be
updated nor maintained by the user, and it therefore focuses on the activities to be performed
by the end user. In this situation, the amount of technical documents needed can be expected
to be low.
Note that these annexes are examples only which can be reduced as well as extended for a
specific purpose. The annexes are noted as informative in this document but the annexes
show an example of text to be used normatively in a product standard, therefore the annexes
use the “shall” instead of “ should”.
All IEC deliverables shall be prepared in accordance with the ISO/IEC Directives, Part 2.
Clause 28 and 29 of the directives regarding the use of figures, including drawings, diagrams
and graphical symbols in publications are based on and refer also to publications described in
the following, i.e. the requirements on documentation in product standards are applicable also
to the publications themselves.
5 Requirements to be covered
5.1 Information requirements
The general purpose of the documentation of a system or a product is to enable its
development, provide information for its manufacturing or assembly, document in test reports
its required properties or performance and to transfer knowledge of the system or product
from the supplier to the user.
The purpose of that part of the documentation accompanying a delivered system or product is
to provide the information necessary for the remaining activities in the life cycle of it, i.e.
usually for the installation and application, the operation and maintenance, and of the
disassembly and recycling.
The amount of information can be very large, and the structuring of it, and thus also the
structuring of the documentation, is therefore important for quick and efficient retrieval of
information. Therefore the requirements in standards shall point out the necessity of well
organized and informative documentation, both with regard to single products and to systems.
The basis for the structuring of information is the assumption that
– descriptive information shall be structured in a way that “models” how a user of the
information perceives the system or product from different aspects, and
– activity related information shall be structured along activities during the life cycle of the
delivered system or product.
Both of these major types of information shall normally be provided. In simpler cases (e.g. a
small consumer product), they may be provided in one single document.
Note that the document kind “Instructions for use” is the minimum set of information that shall
be supplied for any product, see IEC 82079-1.
In more complex cases (e.g. industrial plants and installations with separately defined sub-
systems and components), the information needs to be structured into sets of documents.
The basis for the structure of the sets of documents, i.e. the scope of information to be
presented in each document, is:
a) organize the documentation with regard to the sub-systems and components building up
the entire system or product, see IEC 62023 and IEC 81346-1;
b) within a system or a product or its constituents, prepare the descriptive documentation
with regard to the kind of information contained (for example circuit diagram, assembly
drawing, etc.), see IEC 61355 for possible document kinds;
c) organize the documentation containing activity related information with regard to the life
cycle of the system or product, within the framework defined in accordance with a), see
IEC 61355 for possible document kinds.
The documentation shall be so prepared that duplication of information among the documents
is minimized. Thus, the complete set of documents for a certain system or product prepared
by the manufacturer or supplier in accordance with relevant documentation standards shall be
considered as the basic or the source documentation for that system or product.
The source information (documents, database content, etc.) shall be kept by the owner party
in accordance with the applicable requirements of the ISO 9000 series or for any legal
purposes or policies of the owner party.
Any agreed other requirements on structuring or distribution of documentation in certain
containers (structured to suit the user organisations or to be structured to suit the agreed
types of media to be supplied, etc.) shall be considered copies and may not influence the
structure of the original documentation. In other words, any such supplied document set shall
be considered as a copy. It may be a subset of the original document set.
5.2 Documentation requirements
5.2.1 General
The documentation shall be supplied in the most appropriate form for conveying the
information, for example: drawings, diagrams, charts, tables, instructions (text, audio, and
video). Standards related to products and systems shall not only require that documents
should be included in the delivery but also that the documents shall be prepared and named
in accordance with relevant documentation standards.

– 12 – IEC TS 62666:2016 © IEC 2016
The documentation shall be supplied as a document set on a medium or on media suitable for
the environment where the information is expected to be needed, for example paper,
electronic file on ROM (separated from the delivered system or product or integrated into it),
or via Internet. Due to the varying needs and continuous development in this area, the types
of medium might need to be agreed by the involved parties along the contract.
For the sake of clarification of the responsibility for the delivered system or product and as a
record of the business transaction, the documentation shall at least be delivered as a
document set in non-revisable form.
NOTE As an example of a non-revisable form, the PDF-A format as specified in ISO 19005-1 can be mentioned.
This format is specifically recommended for long archiving periods.
A delivered system or product can be foreseen to be changed or modified after delivery. As a
consequence, its documentation might need to be revised. To facilitate this, the
documentation (or parts of it) might additionally need to be delivered as a document set in
revisable form. Deliveries of revisable document sets should be agreed by the involved
parties along the contract.
5.2.2 Structuring of the documentation
5.2.2.1 General
The structuring is dealt with in the following standards.
IEC 81346-1, Industrial systems, installations and equipment and industrial products –
Structuring principles and reference designations – Part 1: Basic rules (horizontal standard) is
a standard published jointly by IEC and ISO. It describes structuring principles for systems
and products in general, and the subdivision of these into constituent objects.
IEC 62023, Structuring of technical information and documentation (horizontal standard) uses
the structuring principles established in the IEC 81346 series and transforms them into
structuring principles for related information and documentation by requiring that each defined
object shall have a logically self-contained documentation of its own. This principle makes it
possible to include, for example, documentation from sub-suppliers into larger contexts in a
logical way and without any rework.
The IEC 81346 series and IEC 62023 provide a “back bone” for the organization of descriptive
information in the form of documents as well as the organization of the information inside
many documents.
IEC 61355-1, Classification and designation of documents for plants, systems and equipment
– Part 1: Rules and classification tables (horizontal standard) provides further guidance on
how to organize a physically delivered document set and provides also a classification system
for retrieval purposes.
IEC 82079-1, Preparation of instructions for use – Structuring, content and presentation –
Part 1: General principles and detailed requirements (horizontal standard) specifies
requirements for activity related information along the life cycle of the system or product.
5.2.2.2 Consideration of software within a product
Modern products often contain software with associated data, to be executed either
a) by a processor integrated in the product,
b) by a processor or processors elsewhere in the overall system of which the product is a
component, or
c) by any computer (e.g. PC) as a product by itself.

In the first case, in accordance with IEC 81346-1, the software and its associated data is
considered as any other component of the actual product and documented (at least) in the
product-oriented structure of this.
In the second and third case, the software is considered as one or more components of their
own in the overall system. In this case, a software program may be associated with the
relevant component executing it (in the product-oriented structure) and the data sets
associated with the components to which they belong (in the product structure, the function-
oriented structure or both).
In any case, the executing software, integrated or not, shall be documented by documents
included in the ordinary documentation structure for the delivered system or product.
NOTE For software documentation for user guidance systems, see IEC 61506 Industrial-process measurement
and control – Documentation of application software.
5.2.3 Identification and classification
5.2.3.1 Identification and classification of objects within the system or product
Identification is a necessary prerequisite for relating the system or product and its
components to the content of the supplied documentation.
The identification of objects within a supplied system or product is based on the structuring
principles defined in IEC 81346-1: Industrial systems, installations and equipment and
industrial products – Structuring principles and reference designations – Part 1: Basic rules
(horizontal standard).
Together with IEC 81346-2: Industrial systems, installations and equipment and industrial
products – Structuring principles and reference designations – Classification of objects and
codes for classes (horizontal standard), it provides a classification system for objects to be
used together with the structuring principles of IEC 81346-1. Together, these two standards
provide a reference designation system for identification of the defined objects/components
within the supplied system or product, and also of objects in the existing environment such as
rooms and areas.
Within a system, in which several components are connected, there is a need also to
unambiguously identify signals, terminals and cables.
IEC 61175-1, Industrial systems, installations and equipment and industrial products –
Designation of signals – Part 1: Basic rules (horizontal standard), describes how to create
unambiguous designations of signals within a system, based on the reference designations
for objects. The standard contains also a classification system for signals. IEC 61666
Industrial systems, installations and equipment and industrial products – Identification of
terminals within a system (horizontal standard) describes how to create unambiguous
designations of terminals within a system for the purpose of description of electrical and other
networks.
IEC 81714-3 (horizontal standard) contains a classification of networks and product terminals,
which shall be considered in the case of managing multiple types of networks, and products
with different types of terminals connected to different types of networks.
In order to properly associate the objects identified in the documentation with the “real world”
components, etc., labelling of the latter may be required.
Rules for labelling are provided in IEC 81346-1 already mentioned, and in IEC 62491,
Industrial systems, installations and equipment and industrial products – Labelling of cables
and cores.
– 14 – IEC TS 62666:2016 © IEC 2016
NOTE 1 Such labelling is in addition to the usual product marking.
NOTE 2 Related to the use of labelling is the use of graphical symbols on the equipment for the provision of
information to the user. Symbols for use on equipment are contained in IEC 60417 – ISO 7000 DB
(http://www.graphical-symbols.info/equipment ) Graphical symbols for use on equipment. For further information on
how to deal with these in product standards, refer to a guideline published as IEC 62648.
5.2.3.2 Identification of equipment, basic and safety principles
All standards presented in this subclause are designated Basic Safety standards.
General rules for assigning particular meanings to certain visual, acoustic and tactile
indications in order to increase the safety of persons and property are specified in IEC 60073
Basic and safety principles for man-machine interface, marking and identification – Coding
principles for indicators and actuators. IEC 60447 Basic and safety principles for man-
machine interface, marking and identification – Actuating principles establishes general
actuating principles for manually operated actuators forming part of the man-machine
interface associated with electrical equipment, in order to increase the safety through the safe
operation of the equipment.
The identification terminals of electrical equipment and terminations of certain designated
conductors are shown in IEC 60445 Basic and safety principles for man-machine interface,
marking and identification – Identification of equipment terminals, conductor terminations and
conductors. It also provides general rules for the use of certain colours or alphanumeric
notations to identify conductors with the aim of avoiding ambiguity and ensuring safe
operation. Furthermore, minimum requirements and general rules on marking electrical
equipment with ratings and other characteristics to enable the proper and safe selection and
installation of electrical equipment related to any supply of electricity shown in IEC 61293
Marking of electrical equipment with ratings related to electrical supply – Safety requirements.
A minor standard defining letter codes for the designation of some distinct colours to be
applied to the text of descriptions, drawings and markings in the electrotechnical field is
IEC 60757 Code for designation of colours. Additionally, the standard IEC 60152 Identification
by hour numbers of the phase conductors of 3-phase electric systems recommends how to
identify the conductors of 3-phase interconnected systems by the use of hour (clock-face)
numbers of the phase sequence.
5.2.3.3 Identification and classification of documents
All documents shall be identified by a document identification number in order to allow
unambiguous referencing. Identification numbers are normally unambiguous only within a
specific context (defined “domain”). Therefore, several document identification numbers may
be needed. Two domains are essential (but other domains may be required):
– the domain of the issuing organization, and
– the domain created by the system or product per se.
All documents shall be provided with a document identification number that relates it to the
responsible issuer of the document and which is unambiguous within the domain defined by
this issuer.
For complex systems, it is usually advantageous to apply also document designation codes
that classify the documents and relate them to the objects/components within the system.
Aspects of identification of documents are dealt with in a number of standards.
IEC 62023, Structuring of technical information and documentation requires that the
identification of a main document shall have a close relation to the part number that identifies
the object described. IEC 61082-1 Preparation of documents used in electrotechnology –
Part 1: Rules (horizontal standard) contains the basic requirements concerning identification
of documents and the presentation of identification numbers therein.

IEC 61355-1, Classification and designation of documents for plants, systems and equipment
– Part 1: Rules and classification tables (horizontal standard) contains the basic requirements
for classification.
References to these standards are in most cases sufficient in product standards. If it is
required with a deeper look into the subject, the following standards provide additional
requirements:
IEC 62507-1, Requirements for identification systems enabling unambiguous information
interchange – Part 1: Principles and methods (horizontal standard),
IEC 82045-1 and IEC 82045-2, Document management – Part 1: Principles and methods
(horizontal standard), and Part 2: Metadata elements and information reference model
(horizontal standard).
5.2.4 Document kinds, their purpose and preparation
Document kind is a term used to characterize a document with regard to the information
provided and how it is presented. Example: Information on connections can be presented
either in a diagram (connection diagram) or in a table (connection table).
NOTE “Document kind” does not signify “Title”. For further information, refer to IEC 82045-2.
IEC 61355-1, Classification and designation of documents for plants, systems and equipment
– Part 1: Rules and classification tables (horizontal standard) lays down principles for the
naming of document kinds and their encoding, and the associated IEC 61355
(http://std.iec.ch/iec61355) provides information on the expected (and in many cases also
standardized) content of information.
IEC 61082-1, Preparation of documents used in electrotechnology – Part 1: Rules (horizontal
standard), provides general rules for the preparation of documents and specific presentation
rules for the most commonly used document kinds. This standard includes many normative
references to other documentation standards, including such standards issued by ISO. A
reference to IEC 61082-1 therefore implicitly specifies a substantial part of required
references.
IEC 61082-1 provides rules for the most common document kinds such as diagrams (overview
diagrams, function diagrams, circuit diagrams and connection diagrams), drawings (e.g.
arrangement drawings), tables (e.g. connectio
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