IEC 62027:2011

IEC 62027 ®
Edition 2.0 2011-10
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
HORIZONTAL STANDARD
NORME HORIZONTALE
Preparation of object lists, including parts lists

Établissement des listes d’objets, y compris les nomenclatures de composants

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IEC 62027 ®
Edition 2.0 2011-10
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
HORIZONTAL STANDARD
NORME HORIZONTALE
Preparation of object lists, including parts lists

Établissement des listes d’objets, y compris les nomenclatures de composants

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.020 ISBN 978-2-88912-708-5

– 2 – 62027  IEC:2011
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 8
3.1 General terms . 8
3.2 Terms related to documentation . 10
3.3 Specific terms related to object lists . 11
3.4 Alphabetical index of terms . 12
4 General . 12
4.1 Types of object lists . 12
4.2 Forms of presentation of an object list body . 13
4.3 Table header . 13
4.4 List items. 14
5 Requirements for the parts list body . 14
5.1 Classification of parts lists . 14
5.2 Relation to the specified object . 14
5.3 Content of a list item . 15
5.4 Specification of characteristic properties . 16
5.4.1 Overview . 16
5.4.2 Identification of the occurrence . 16
5.4.3 Usage . 16
5.4.4 Characteristic properties related to the occurrence . 17
5.4.5 References related to the occurrence . 17
5.4.6 Amount . 17
5.4.7 Identification of the type of part . 17
5.4.8 Description of the type of part . 18
5.4.9 Characteristic properties for the type of part . 19
5.4.10 References to documents related to the type of part . 19
5.5 Layout of the parts list body . 20
5.5.1 General . 20
5.5.2 Columns in Class A parts lists . 20
5.5.3 Columns in Class B parts lists . 21
5.5.4 List items . 21
5.5.5 Sorting of list items . 21
6 Requirements for an object list document . 22
6.1 General . 22
6.2 Document kind names . 22
Annex A (informative) Presentation of characteristic properties in a list item . 23
Annex B (normative) Data element type definitions . 25
Annex C (informative) Example of a parts list (object list) document with an parts list

body of Class A . 28
Annex D (informative) Example of a parts list (object list) document with a parts list
body of Class B . 29

62027  IEC:2011 – 3 –
Annex E (informative) Example of a parts list document for manufacturing purposes
with a parts list body of Class A . 30
Bibliography . 32

Figure 1 – Illustration of the organization of object lists (in one aspect) . 6
Figure 2 – Presentation of an object list body in a document . 13

Table 1 – Information contained in a list item for a constituent object . 15

– 4 – 62027  IEC:2011
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
PREPARATION OF OBJECT LISTS, INCLUDING PARTS LISTS

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
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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.
International Standard IEC 62027 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 published in 2000. 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 81346-1:2009:2009, IEC 62507-1:2010:2010 and IEC/PAS 62569-1:2009;
 the term “object list” has been introduced as the generic term, and “parts list” used as a
specific term for object lists associated with the product structure;
 Annex A of the previous edition has been taken away and partly replaced by 6.2 and a
reference to IEC 61355 DB;
 a new Annex A providing guidance on the presentation of subsets of characteristic
properties has been introduced;

62027  IEC:2011 – 5 –
• a new Annex B providing source definitions and references to used data element types
has been introduced;
• the examples in the annexes C, D and E (corresponding to B, C and D in the previous
edition) have been provided with comments;
The text of this standard is based on the following documents:
FDIS Report on voting
3/1049/FDIS 3/1070/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.
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.
– 6 – 62027  IEC:2011
INTRODUCTION
An object list is primarily used to list and specify the constituent objects (components) of the
overall object or system to which the object list applies.
It is generally recognized that information on products, installations and systems can be
organized on the basis of tree-like, hierarchical, structures. The structure represents the way
in which an industrial system or a product is divided into sub-systems or components,
designated by the general term “constituent objects”. In the context of this International
Standard, ”object” refers to any entity treated in a process of development, implementation,
usage and disposal of a plant, installation, system, equipment, etc., or part thereof, in
accordance with the definition in 3.1.1.
NOTE In the context of other standards, the term “item” is sometimes used with the same meaning as “object”.
Depending on the “aspect” different structures can be recognized, for example a “product-
oriented structure”, a “function-oriented structure” or a “location-oriented structure”. A specific
constituent object may be of relevance in one structure only, or in more than one. For further
information on structures and structuring (see IEC 81346-1:2009).
An object list is implicitly or explicitly associated with such a structure. The object list concept
described in this International Standard is therefore applicable in all structures defined in
accordance with IEC 81346-1:2009.
Object lists relevant to the manufacturing and assembly of a product, associated with the
product-oriented structure, and generally named parts lists, usually cover only one assembly
level each, and the main assembly is normally described by a system of single-level parts
lists. An example of a system of single-level parts lists is shown in Figure 1.
Object lists are often generated as reports from a database containing information on the
entire structure.
Level 0 .
A
Level 1 .
C
B
Level 2 .

1 2 E 3
D 4
Level 3 .

3 6 8
5 7 9
.
IEC  2145/11
NOTE A is the main assembly; B, C, D and E are sub-assemblies; 1, 2, 3, etc. are parts. A, B, C, D and E are
defined by single level parts lists, the content of each indicated by means of dashed lines.
Figure 1 – Illustration of the organization of object lists (in one aspect)

62027  IEC:2011 – 7 –
PREPARATION OF OBJECT LISTS, INCLUDING PARTS LISTS

1 Scope
This International Standard provides rules and guidelines for the presentation of information
in object lists, and specific rules for such documents. It is applicable to object lists such as
parts lists, function lists and location lists used in the design and engineering process
intended to be supplied with the documentation.
NOTE 1 The scope of such object lists covers either an object with occurring constituents (c.f. IEC 81346-1:2009)
or an assembly with types of constituents (c.f. ISO 7573).
NOTE 2 The role of such lists as a main document in structured documentation is described in IEC 62023:-.
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 61082-1:2006, Preparation of documents used in electrotechnology – Part 1: Rules
IEC 61355:2008, IEC Collection of standardized and established document kinds, available at
http://std.iec.ch/iec61355
IEC 61355-1:2008, Classification and designation of documents for plants, systems and
equipment – Part 1: Rules and classification tables
IEC 61360, Component data dictionary (CDD).Available from: http://std.iec.ch/iec61360
IEC 62023 , Structuring of technical information and documentation
IEC 62507-1:2010, Identification systems enabling unambiguous information interchange –
Requirements – Part 1: Principles and methods
IEC 81346-1:2009, Industrial systems, installations and equipment and industrial products –
Structuring principles and reference designation – Part 1: Basic rules
IEC 81346-2, Industrial systems, installations and equipment and industrial products –
Structuring principles and reference designations – Part 2: Classification of objects and codes
for classes
IEC 82045-2:2004, Document management – Part 2: Metadata elements and information
reference model
IEC/PAS 62569-1:2009, Generic specification of information on products – Part 1: Principles
and methods
ISO 639-1, Codes for the representation of names of languages – Part 1: Alpha-2 code
ISO 6433, Technical drawings – Item references
—————————
In preparation.
– 8 – 62027  IEC:2011
ISO 7200, Technical product documentation – Data fields in title blocks and document
headers
ISO 13584-42:2010, Industrial automation systems and integration – Parts library – Part 42:
Description methodology: Methodology for structuring parts families
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply. In the
definitions, terms that are defined elsewhere in this clause are shown in italics.
An alphabetical index of the terms is contained in 3.4.
NOTE Definitions taken over from other International Standards are not necessarily literally cited, but adapted to
the form required for definitions according to the ISO/IEC Directives.
3.1 General terms
3.1.1
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 81346-1:2009, definition 3.1]
3.1.2
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.
[IEC 81346-1:2009, definition 3.2]
3.1.3
aspect
specified way of viewing an object
[IEC 81346-1:2009, definition 3.3]
3.1.4
structure
organization of relations among objects of a system describing constituency-relations
(consists of/is a part of)
[IEC 81346-1:2009, definition 3.9]

62027  IEC:2011 – 9 –
3.1.5
occurrence (of an object)
particular case implying that an object appears in a system
3.1.6
domain
distinguished part of an abstract or physical space where something exists
NOTE A domain can be e.g. an organization or a country or a part of it.
[IEC 62507-1:2010, definition 3.2]
3.1.7
identifier
attribute associated with an object to unambiguously identify it in a specified domain
NOTE In an identification system several types of identifiers may be required.
[IEC 62507-1:2010, definition 3.8]
3.1.8
identification number
ID
string of characters representing the value of the identifier
NOTE 1 It is practice that although the term says “number” the string can contain other types of characters as
well.
NOTE 2 Note that the term “identifier” 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 Identification numbers are often required to be unique (an object 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.
[IEC 62507-1:2010, definition 3.5]
3.1.9
domain number
domain ID
identification number assigned to a domain
NOTE An assigned domain number can coincide with the organization ID.
[IEC 62507-1:2010, definition 3.3]
3.1.10
reference designation
identifier of a specific object with respect to the system of which the object is a constituent,
based on one or more aspects of that system
[IEC 81346-1:2009, definition 3.11]
NOTE If a set of drawings for a product is structurally based on consist-of/is-part-of relations, part reference
numbers are virtually the same thing as numeric product-oriented reference designations.
3.1.11
reference designation set
collection of two or more reference designations assigned to an object of which at least one
unambiguously identifies this object

– 10 – 62027  IEC:2011
[IEC 81346-1:2009, definition 3.14]
3.1.12
part
material or functional element that is intended to constitute a component of a product
[ISO 13584-1 definition 3.1.16 modified]
3.1.13
part reference
identification of component parts of assemblies and/or the identification of individual parts on
the same drawing
[ISO 7573, definition 3.2]
NOTE Part references are valid within the domain of an identified document (i.e. they refer to occurring types of
objects in an identified document); as opposed to reference designations that are valid within of a defined structure
(i.e. they refer to occurrences of sub-objects in an identified structure). Identical parts on a drawing are required to
have the same part reference, preferably a number, according to ISO 6433, while each occurrence of an object in a
structure is required to have a unique reference designation according to IEC 81346-1:2009.
3.1.14
part number
part ID
identification number of a part
3.1.15
characteristic property
defined parameter suitable for the description and differentiation of objects
NOTE The term characteristic property used in this standard is not identical with the term data element type used
in IEC 61360-1:2009. A data element type is a unit of data for which the identification, description and value
representation have been specified in the context of a dictionary, while the term characteristic property is used for
an occurrence of such a data element type in the context of a specification of an object. This distinction makes it
possible to qualify a characteristic property in an object specification and still refer to the same data element type
definition in the dictionary.
The term used in IEC/PAS 62569-1:2009 is “property”, but it has been decided to change to “characteristic
property” in this context since ISO uses “property” as synonym to “data element type”.
[based on IEC/PAS 62569-1:2009]
3.1.16
type
class of things having common characteristics
3.1.17
data element type
DET
unit of data for which the identification, description and value representation have been
specified
[based on IEC 61360-1:2009, definition 2.3]
3.2 Terms related to documentation
3.2.1
document
fixed and structured amount of information that can be managed and interchanged as a unit
between users and systems
NOTE 1 This unit may not necessarily be human perceptible. Information is usually stored on a data medium.

62027  IEC:2011 – 11 –
NOTE 2 The term document is not restricted to its meaning in a legal sense.
NOTE 3 A document can be designated in accordance with the type of information and the form of presentation,
for example overview diagram, connection table, function chart.
[IEC 61082-1:2006, definition 3.1.2 and IEC 82045-1:2001, definition 3.2.3, modified]
3.2.2
document number
document ID
identification number assigned to a document
[based on IEC 82045-2:2004, (clause 8 No. 2)]
3.2.3
document kind
type of document defined with respect to its specified content of information and form of
presentation
NOTE Sometimes the term document type is used for the same concept.
[IEC 61355-1:2008, definition 3.6]
3.2.4
document kind class
group of document kinds having similar characteristics concerning the content of information
independent of the form of presentation
[IEC 61355-1:2008, definition 3.7]
3.3 Specific terms related to object lists
3.3.1
list item
presentation as part of a table or list of an ordered set of characteristic property values
pertaining to one specific object
3.3.2
object list body
table containing list items specifying the objects that constitute an assembly (or sub-
assembly) or system and, if necessary, reference documents
3.3.3
parts list body
object list body associated with the product-oriented structure
3.3.4
function list body
object list body associated with the function-oriented structure
3.3.5
location list body
object list body associated with the location-oriented structure
3.3.6
object list (document)
document mainly containing an object list body together with administrative document
information
– 12 – 62027  IEC:2011
3.3.7
parts list (document)
object list mainly containing a parts list body
3.3.8
function list (document)
object list mainly containing a function list body
3.3.9
location list (document)
object list mainly containing a location list body
3.4 Alphabetical index of terms

Term Term number Term Term number
aspect 3.1.3 location list body 3.3.5
characteristic property 3.1.15 object 3.1.1
data element type 3.1.17 object list (document) 3.3.6
document 3.2.1 object list body 3.3.2
document ID 3.2.2 occurrence (of an object) 3.1.5
document kind 3.2.3 part 3.1.12
document kind class 3.2.4 part ID 3.1.14
document number 3.2.2 part number 3.1.14
domain 3.1.6 part reference 3.1.13
domain ID 3.1.9 parts list (document) 3.3.7
domain number 3.1.9 parts list body 3.3.3
function list (document) 3.3.8 reference designation 3.1.10
function list body 3.3.4 reference designation set 3.1.11
ID 3.1.8 structure 3.1.4
identification number 3.1.8 system 3.1.2
identifier 3.1.7 type 3.1.16
list item 3.3.1
location list (document) 3.3.9
4 General
4.1 Types of object lists
Object lists are used to list and possibly specify the constituents of a system or product. With
regard to the scope of object lists it is useful to differentiate among:
• “structure-based” object lists (in which the domain of validity is defined by the content
(identified occurrences of sub-objects) of an object in a defined structure);
• “document-based” object lists (in which the domain of validity is defined by the content
(identified occurring types of objects) of an identified document).
NOTE In addition to the object lists specified in this standard there are, for example, “category-based” object lists
like motor lists and valve lists used during the design and engineering process. Such lists can apply principles
similar to those provided in this standard, but are not specifically treated here in.
Structure-based object lists can be further differentiated depending on the applied structure
(see IEC 81346-1:2009):
62027  IEC:2011 – 13 –
• a parts list contains constituent objects in accordance with the product-oriented structure;
• a function list contains constituent objects in accordance with the function-oriented
structure;
• a location list contains constituent objects in accordance with the location-oriented
structure;
• etc.
Since the parts list is the most commonly used type of object list, this is in detail described in
Clause 5. Other structure-based lists are organized in accordance with other structures as
described above, but are otherwise constructed in the same way.
4.2 Forms of presentation of an object list body
An object list body is a tabular presentation of list items representing constituent objects of an
object.
NOTE Parts and components are often used as alternative terms for constituent objects.
An object list body can be presented:
– in a basic object list document (see Clause 6), or
– as a part of a composite document, for example the drawing presenting the assembled
object with which it is associated.
See Figure 2.
Object list body
Table header
E.g. drawing
Table header
Table header
Title block Title block
Object list body presented as a Object list body presented as a part of a composite
basic object list document kind document kind

IEC  2146/11
Figure 2 – Presentation of an object list body in a document
4.3 Table header
The table header defines the columns of the object list body. A column may be used to
present the values of one or more characteristic properties.

– 14 – 62027  IEC:2011
4.4 List items
A list item in the object list represents one constituent object and presents the values of a
selection of its characteristic properties. Every constituent object within the scope of the
object list is represented by one list item; see also 5.3.
5 Requirements for the parts list body
5.1 Classification of parts lists
The following classes of parts lists are recognized in this International Standard.
Class A
Parts lists in which each list item represents a type (see 3.1.16) of a constituent object
and specifies the amount of such types.
NOTE 1 Class A deals with “Summarized lists”; the amount is often greater than one for each type, the
part number of each object may be used as ‘key’. This class of parts list is referred to as ”bill-of-material
(BOM) data structure” in ISO 10303-44.
Class B
Parts lists in which each list item represents an occurrence (see 3.1.5) of a constituent
object.
NOTE 2 For Class B the amount is in principle equal to one in each list item, the reference designation
for the constituent object may be used as ‘key’. This class of parts list is referred to as “parts list data
structure” in ISO 10303-44.
In cases where there is a need to specify a set of several identical objects, and if there is no need to
distinguish between them in any context in the documentation, this set may be treated as one occurrence,
in which the specified amount is larger than one. Example: the hundreds of light emitting diodes
assembled to form a traffic signal.
Class A parts lists are commonly used in mechanical design of discrete objects, especially if
only one structural level is covered by the parts list.
Class B parts lists are commonly used for electrical, fluid and other comprehensive systems,
where there is a need to identify each occurrence of a type, for example for connection
purposes.
In this International Standard, requirements for both classes are specified.
5.2 Relation to the specified object
Any document in design and engineering, including parts lists, should be related to one
object.
The parts list shall list and possibly specify the constituent objects of that object. Each
constituent object is presented by means of a list item.
A parts list may present one structural level only or one level together with one or more lower
levels.
NOTE 1 For further information on the concept “object”, see IEC 81346-1:2009.
NOTE 2 For further information on the relation of "objects" to associated documents and documentation; see also
IEC 61355-1:2008 and IEC 62023:-.

62027  IEC:2011 – 15 –
NOTE 3 Parts lists covering more than one structural level are referred to as “indented parts lists” in
ISO 10303-44.
5.3 Content of a list item
The basic purpose of each list item is to associate the occurrence of a constituent object
(Class B), or each identified group of objects of the same type (Class A), with a (type of) part.
The occurrence is identified by a reference designation or part reference and the part by a
part number or global identification number.
In addition, other information on the occurrence and on the part may be provided to make the
parts list more easily comprehensible and useful.
NOTE 1 In some cases there is a need to associate the occurrence of the constituent object not only with a part
number, but also with a specific specimen of that type of part, identified by a serial number.
Each list item shall include the mandatory information specified in table 1 and should provide
possibilities for inclusion of the conditional or optional information.
NOTE 2 For parts lists created from a database, system internal object identifiers may be needed. Such
identifiers are not dealt with in this standard.
Table 1 – Information contained in a list item for a constituent object
Information Class Class Reference to clause
A B
Part reference Mandatory 5.4.2 Identification of the occurrence
Amount Mandatory Conditional 5.4.6 Amount
Listing of reference Conditional - 5.4.2 Identification of the occurrence
designations
Reference designation - Mandatory 5.4.2 Identification of the occurrence
Reference designation set - Conditional 5.4.2 Identification of the occurrence
Usage - Conditional 5.4.3 Usage
Occurrence-related technical - Conditional 5.4.4 Characteristic properties related to the
data occurrence
Occurrence-related document - Conditional 5.4.5 References related to the occurrence
reference
Part number, or Mandatory Mandatory 5.4.7 Identification of the type of part
Global identifier Mandatory Mandatory 5.4.7 Identification of the type of part
Part name Mandatory Mandatory 5.4.7 Identification of the type of part
Type designation Conditional Conditional 5.4.8 Description of the type of part
Specifying technical data Conditional Conditional 5.4.9 Characteristic properties for the type of part
Descriptive technical data Optional Optional 5.4.9 Characteristic properties for the type of part
Mass, dimensions Conditional Conditional 5.4.9 Characteristic properties for the type of part
Document reference Optional Optional 5.4.10 References to documents related to the
type of part
Remark Optional Optional
NOTE The terms used to specify the obligation have the following meaning in this table:
Mandatory = always required
Conditional = always required if the information is available
Optional = user's choice
– 16 – 62027  IEC:2011
5.4 Specification of characteristic properties
5.4.1 Overview
In this sub-clause, the information listed in table 1 is described in the following order:
a) information associated with the occurrence of the constituent object:
1) identification of the occurrence;
2) usage;
3) occurrence-related technical data;
4) reference(s) related to the occurrence;
b) information associated with amount and dimensions;
c) information associated with the type of the constituent object:
1) identification of the type;
2) description of the type;
3) references related to the type.
Each characteristic property is in this standard specified by its name, definition, and possibly
a comment.
For the rigorous identification and specification of the data element types used to express the
characteristic properties reference is made to IEC 61360 DB and ISO 13584-42 compliant
standards and to IEC 82045-2:2004.
5.4.2 Identification of the occurrence
The occurrence of a part shall be identified by at least one reference designation or a part
reference.
Reference designation sets may also be provided. If a reference designation set is provided
then the characteristic property “reference designation” is repeated once for each member of
the set.
NOTE IEC 81346-1:2009 provides rules on how to present a reference designation set on one line.
Example: A set consisting of the two reference designations =K1=B1 and +U5+U23 should be written
=K1=B1/+U5+23.
Name Definition Comment
Reference designation identifier of a specific object with respect For Class B lists, this property is used for
to the system of which the object is a the sorting of the list items.
constituent, based on one or more
aspects of that system (IEC 81346-
1:2009)
Part reference identification of component parts of For Class A lists, this property is used for
assemblies and/or the identification of the sorting of the list items.
individual parts on the same drawing As one list item may cover several
(ISO 6433) occurrences, the reference designation is
in this case not suitable for sorting
purposes.
NOTE The table heading “Name” above and in the following refers usually to the “Preferred name” defined for a
DET, but may in some applications of object lists be replaced by a synonym to this.
5.4.3 Usage
If required, for lists of Class B, information should be added relating to the usage or purpose
of the specific occurrence. Examples for a push-button: “Start”, “Stop”.
Name Definition Comment
62027  IEC:2011 – 17 –
Usage free text description of the use or
purpose of the object occurrence

5.4.4 Characteristic properties related to the occurrence
Technical data giving specific characteristics for the occurrence may be provided.
Example: Pre-set value (selected within a “Setting range” relevant to the type).
The selection of relevant characteristic properties depends on the type of constituent object
(component class), and cannot be generally specified. The referenced data element types
should, if possible, be selected from valid international standards, such as IEC 61360 DB.
5.4.5 References related to the occurrence
Reference to documents giving information for adaptation of the specified type of part to the
use in the specific occurrence, shall be given if necessary.
If necessary, references to other documents describing the occurrence of the constituent
object, for example circuit diagrams or assembly drawings shall be provided.
For metadata associated with such document references, see 5.4.10.
For reference to a specific page and zone within a document the referencing rules of
IEC 61082-1:2006 shall be applied.
5.4.6 Amount
The amount is either expressed as
• number of pieces;
• value, consisting of a measure together with a unit.

Name Definition Comment
Amount number of pieces or a specifying value of In many cases the term “quantity” is used
identical specimen of the specified type for this concept, but this term may be
misinterpreted in relation to the use of this
term in the 80000-series of standards on
Quantities and units prepared jointly by
IEC and ISO.
Unit the value of a quantity chosen by Appropriate units for e.g. length, area,
convention as a reference for measuring volume or mass are defined in ISO 1000.
quantities of the same kind
NOTE According to ISO 80000 the
(language independent) unit symbol for
piece is “1
...