IEC 62541-23:2025
(Main)OPC unified architecture - Part 23: Common ReferenceTypes
OPC unified architecture - Part 23: Common ReferenceTypes
IEC 62541-23:2025 defines ReferenceTypes commonly used in industrial Information Models. They are more specific than the ReferenceTypes in IEC 62541‑3 which are an inherent part of the OPC UA Address Space Model.
Architecture unifiée OPC - Partie 23: ReferenceTypes communs
IEC 62541-23: 2025 définit les ReferenceTypes communément utilisés dans les Modèles d'information industriels. Ces ReferenceTypes sont plus spécifiques que ceux de l'IEC 62541‑3 qui font partie intégrante du Modèle d'espace d'adressage OPC UA.
General Information
Standards Content (Sample)
IEC 62541-23 ®
Edition 1.0 2025-12
INTERNATIONAL
STANDARD
OPC unified architecture -
Part 23: Common ReferenceTypes
ICS 25.040 ISBN 978-2-8327-0837-8
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CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms, definitions and abbreviated terms . 5
3.1 Terms and definitions . 5
3.2 Abbreviated terms. 5
4 OPC UA ReferenceTypes . 5
4.1 Overview . 5
4.2 IsExecutableOn . 6
4.2.1 Overview . 6
4.2.2 Definition . 6
4.3 IsExecutingOn . 7
4.3.1 Overview . 7
4.3.2 Definition . 7
4.4 Controls . 8
4.4.1 Overview . 8
4.4.2 Definition . 8
4.5 Utilizes . 9
4.5.1 Overview . 9
4.5.2 Definition . 9
4.6 Requires . 9
4.6.1 Overview . 9
4.6.2 Definition . 10
4.7 IsPhysicallyConnectedTo. 10
4.7.1 Overview . 10
4.7.2 Definition . 10
4.8 RepresentsSameEntityAs . 11
4.8.1 Overview . 11
4.8.2 Definition . 11
4.9 RepresentsSameHardwareAs . 12
4.9.1 Overview . 12
4.9.2 Definition . 12
4.10 RepresentsSameFunctionalityAs . 13
4.10.1 Overview . 13
4.10.2 Definition . 13
4.11 IsHostedBy . 14
4.11.1 Overview . 14
4.11.2 Definition . 14
4.12 HasPhysicalComponent. 14
4.12.1 Overview . 14
4.12.2 Definition . 15
4.13 HasContainedComponent . 15
4.13.1 Overview . 15
4.13.2 Definition . 15
4.14 HasAttachedComponent . 16
4.14.1 Overview . 16
4.14.2 Definition . 16
5 Reference Description . 17
5.1 Overview . 17
5.2 Reference refinement . 18
5.3 OPC UA VariableTypes . 20
5.3.1 Overview . 20
5.3.2 ReferenceDescriptionVariableType . 20
5.4 OPC UA ReferenceTypes . 20
5.4.1 Overview . 20
5.4.2 HasReferenceDescription . 20
5.5 OPC UA DataTypes . 21
5.5.1 ReferenceDescriptionDataType . 21
5.5.2 ReferenceListEntryDataType . 22
Annex A (informative) ReferenceDescription Design Decisions . 23
A.1 Overview . 23
A.2 Alternative Approach: Intermediate Object. 23
Bibliography . 24
Figure 1 – Overview of ReferenceTypes . 6
Figure 2 – Example of ReferenceDescriptions . 17
Figure 3 – Examples of Reference refinements . 18
Figure 4 – Example of Reference refinements with multiple path options . 18
Figure 5 – Example of how to use Reference refinements . 19
Figure 6 – Example of how to use Reference refinements with two levels and multiple
hops. 19
Figure A.1 – Refinement of References by Proxy Object . 23
Table 1 – IsExecutableOn definition . 7
Table 2 – IsExecutingOn definition . 8
Table 3 – Controls definition . 8
Table 4 – Utilizes definition . 9
Table 5 – Requires definition . 10
Table 6 – IsPhysicallyConnectedTo definition . 11
Table 7 – RepresentsSameEntityAs definition . 12
Table 8 – RepresentsSameHardwareAs definition . 13
Table 9 – RepresentsSameFunctionalityAs definition . 13
Table 10 – IsHostedBy definition . 14
Table 11 – HasPhysicalComponent definition . 15
Table 12 – HasContainedComponent definition . 16
Table 13 – HasAttachedComponent definition . 16
Table 14 – ReferenceDescriptionVariableType definition . 20
Table 15 – HasReferenceDescription definition . 21
Table 16 – ReferenceDescriptionDataType structure . 21
Table 17 – ReferenceDescriptionDataType definition . 22
Table 18 – ReferenceListEntryDataType structure . 22
Table 19 – ReferenceListEntryDataType definition . 22
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
OPC unified architecture -
Part 23: Common ReferenceTypes
FOREWORD
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IEC 62541-23 has been prepared by subcommittee 65E: Devices and integration in enterprise
systems, of IEC technical committee 65: Industrial-process measurement, control, and
automation. It is an International Standard.
The text of this International Standard is based on the following documents:
Draft Report on voting
65E/1048/CDV 65E/1105/RVC
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/publications.
Throughout this document and the other Parts of the series, certain document conventions are
used:
Italics are used to denote a defined term or definition that appears in the "Terms and definitions"
clause in one of the parts of the series.
Italics are also used to denote the name of a service input or output parameter or the name of
a structure or element of a structure that are usually defined in tables.
The italicized terms and names are also often written in camel-case (the practice of writing
compound words or phrases in which the elements are joined without spaces, with each
element's initial letter capitalized within the compound). For example, the defined term is
AddressSpace instead of Address Space. This makes it easier to understand that there is a
single definition for AddressSpace, not separate definitions for Address and Space.
A list of all parts of the IEC 62541 series, published under the general title OPC Unified
Architecture, can be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
– reconfirmed,
– withdrawn, or
– revised.
1 Scope
This part of IEC 62541 defines ReferenceTypes commonly used in industrial Information
Models. They are more specific than the ReferenceTypes in IEC 62541-3 which are an inherent
part of the OPC UA Address Space Model.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies.
For undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 62541-1, OPC Unified Architecture - Part 1: Overview and Concepts
IEC 62541-3, OPC Unified Architecture - Part 3: Address Space Model
IEC 62541-5, OPC Unified Architecture - Part 5: Information Model
3 Terms, definitions and abbreviated terms
3.1 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 62541-1,
IEC 62541-3, and IEC 62541-5 apply.
ISO and IEC maintain terminology databases for use in standardization at the following
addresses:
– IEC Electropedia: available at https://www.electropedia.org/
– ISO Online browsing platform: available at https://www.iso.org/obp
3.2 Abbreviated terms
CPU Central Processing Unit
IO Input/Output
IP Internet Protocol
PC Personal Computer
PCI Peripheral Component Interconnect
PHY Physical Layer
PLC Programmable Logic Controller
RFID Radio Frequency Identification
4 OPC UA ReferenceTypes
4.1 Overview
Figure 1 gives an overview of the ReferenceTypes defined in the following subsections.
Figure 1 – Overview of ReferenceTypes
4.2 IsExecutableOn
4.2.1 Overview
This ReferenceType can be used to expose the relation between a software component and its
execution environment. For example, it can be used to expose which firmware (including its
version) is available on a field device.
4.2.2 Definition
The IsExecutableOn is a concrete ReferenceType and can be used directly. It is a subtype of
NonHierarchicalReferences.
The semantic of this ReferenceType is to relate a software component to its execution
environment that is required to run the software (e.g. Hardware component, Task or Thread).
The relationship shows that the execution environment the reference points to, is able to
execute the software component. This does not imply that the software component is currently
being executed or running. To show that the software is running in an environment,
IsExecutingOn should be used.
The SourceNode of References of this ReferenceType shall be an Object or ObjectType
representing a software component.
The TargetNode of References of this ReferenceType shall be an Object or ObjectType
representing an execution environment for a software component, which can be a piece of
hardware (e.g. Device) or some other environment like a task, thread, or software execution
framework.
IsExecutableOn is formally defined in Table 1.
Table 1 – IsExecutableOn definition
Attributes Value
BrowseName IsExecutableOn
InverseName CanExecute
Symmetric FALSE
IsAbstract FALSE
References NodeClass BrowseName Comment
Subtype of NonHierarchicalReferences defined in IEC 62541-5
Conformance Units
Base Info IsExecutableOn
4.3 IsExecutingOn
4.3.1 Overview
This ReferenceType can be used to expose the relation between a software component and its
execution environment it is currently executing on. References of this ReferenceType can be
very dynamic and will disappear as soon as the software component is not being executed
anymore. For example, it can be used to expose that a PLC program is currently running on a
specific task of a PLC.
4.3.2 Definition
The IsExecutingOn is a concrete ReferenceType and can be used directly. It is a subtype of
Utilizes.
The semantic of this ReferenceType is to relate a software component to its execution
environment it is currently executing on (e.g. Hardware component, Task or Thread).
References of this ReferenceType shall only be used when the software component is currently
executed / running.
The SourceNode of References of this ReferenceType shall be an Object or ObjectType
representing a software component.
The TargetNode of References of this ReferenceType shall be an Object or ObjectType
representing an execution environment for a software component, which can be a piece of
hardware (e.g. Device) or some other environment like a task, thread or software execution
framework.
IsExecutingOn is formally defined in Table 2.
Table 2 – IsExecutingOn definition
Attributes Value
BrowseName IsExecutingOn
InverseName Executes
Symmetric FALSE
IsAbstract FALSE
References NodeClass BrowseName Comment
Subtype of Utilizes defined in 4.5
Conformance Units
Base Info IsExecutingOn
4.4 Controls
4.4.1 Overview
This ReferenceType can be used to expose the relation between an object controlling other
objects and the controlled objects. For example, it can be used to relate a PLC to the field
devices or machine-modules controlled by the PLC or a software component to the hardware
components controlled by the software component.
4.4.2 Definition
The Controls is a concrete ReferenceType and can be used directly. It is a subtype of
HierarchicalReferences.
The semantic of this ReferenceType is to relate the controlling component to the components
controlled by the controlling component.
The SourceNode of References of this ReferenceType shall be an Object or ObjectType
representing the controlling component, as for example a PLC or a software component.
The TargetNode of References of this ReferenceType shall be an Object representing a
component that is controlled by the TargetNode.
Controls is formally defined in Table 3.
Table 3 – Controls definition
Attributes Value
BrowseName Controls
InverseName IsControlledBy
Symmetric FALSE
IsAbstract FALSE
References NodeClass BrowseName Comment
Subtype of HierarchicalReferences defined in IEC 62541-5
Conformance Units
Base Info Controls
4.5 Utilizes
4.5.1 Overview
This ReferenceType can be used to expose the relation between a component to other
components, that the component needs in order to work. In contrast to the Requires
ReferenceType, this non-hierarchical ReferenceType allows loops, e.g. both components need
each other in order to work. In that case, there would be two References, the first one pointing
from one component to the other, and the second one vice versa. For example, a fan in a PC
needs the power supply in order to work and the power supply needs the cooling from the fan,
that it is not overheating. An example of a non-looping usage is that a robot utilizes a vision
system in order to get the position where to grab something.
4.5.2 Definition
The Utilizes is a concrete ReferenceType and can be used directly. It is a subtype of
NonHierarchicalReferences.
The semantic of this ReferenceType is to relate a component to other components that are
needed by the component in order to work.
The SourceNode of References of this ReferenceType shall be an Object or ObjectType
representing a component that utilizes the TargetNode in order to work.
The TargetNode of References of this ReferenceType shall be an Object or ObjectType
representing the required component.
Requires is formally defined in Table 4.
Table 4 – Utilizes definition
Attributes Value
BrowseName Utilizes
InverseName IsUtilizedBy
Symmetric FALSE
IsAbstract FALSE
References NodeClass BrowseName Comment
Subtype of NonHierarchicalReferences defined in IEC 62541-5
Conformance Units
Base Info Utilizes
4.6 Requires
4.6.1 Overview
This ReferenceType can be used to expose the relation between a component to other
components, that the component requires in order to work. In contrast to the HasComponent
ReferenceType, the related components are not considered to be subcomponents of the
component. In contrast to the Utilizes ReferenceType, this hierarchical
...
IEC 62541-23 ®
Edition 1.0 2025-12
NORME
INTERNATIONALE
Architecture unifiée OPC -
Partie 23: ReferenceTypes communs
ICS 25.040 ISBN 978-2-8327-0837-8
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SOMMAIRE
AVANT-PROPOS . 3
1 Domaine d'application . 5
2 Références normatives . 5
3 Termes, définitions et abréviations . 5
3.1 Termes et définitions. 5
3.2 Abréviations . 5
4 ReferenceTypes OPC UA . 5
4.1 Vue d'ensemble . 5
4.2 IsExecutableOn . 6
4.2.1 Vue d'ensemble . 6
4.2.2 Définition . 6
4.3 IsExecutingOn . 7
4.3.1 Vue d'ensemble . 7
4.3.2 Définition . 7
4.4 Controls . 8
4.4.1 Vue d'ensemble . 8
4.4.2 Définition . 8
4.5 Utilizes . 9
4.5.1 Vue d'ensemble . 9
4.5.2 Définition . 9
4.6 Requires . 9
4.6.1 Vue d'ensemble . 9
4.6.2 Définition . 10
4.7 IsPhysicallyConnectedTo. 10
4.7.1 Vue d'ensemble . 10
4.7.2 Définition . 10
4.8 RepresentsSameEntityAs . 11
4.8.1 Vue d'ensemble . 11
4.8.2 Définition . 11
4.9 RepresentsSameHardwareAs . 12
4.9.1 Vue d'ensemble . 12
4.9.2 Définition . 12
4.10 RepresentsSameFunctionalityAs . 13
4.10.1 Vue d'ensemble . 13
4.10.2 Définition . 13
4.11 IsHostedBy . 14
4.11.1 Vue d'ensemble . 14
4.11.2 Définition . 14
4.12 HasPhysicalComponent. 14
4.12.1 Vue d'ensemble . 14
4.12.2 Définition . 15
4.13 HasContainedComponent . 15
4.13.1 Vue d'ensemble . 15
4.13.2 Définition . 15
4.14 HasAttachedComponent . 16
4.14.1 Vue d'ensemble . 16
4.14.2 Définition . 16
5 Description des Références . 17
5.1 Vue d'ensemble . 17
5.2 Affinement de Référence . 18
5.3 VariableTypes OPC UA . 20
5.3.1 Vue d'ensemble . 20
5.3.2 ReferenceDescriptionVariableType . 20
5.4 ReferenceTypes OPC UA . 21
5.4.1 Vue d'ensemble . 21
5.4.2 HasReferenceDescription . 21
5.5 DataTypes OPC UA . 22
5.5.1 ReferenceDescriptionDataType . 22
5.5.2 ReferenceListEntryDataType . 22
Annexe A (informative) Décisions de conception relatives à la ReferenceDescription . 24
A.1 Vue d'ensemble . 24
A.2 Approche alternative: Objet intermédiaire . 24
Bibliographie . 25
Figure 1 – Vue d'ensemble des ReferenceTypes . 6
Figure 2 – Exemple de ReferenceDescriptions . 17
Figure 3 – Exemples d'affinements de Références . 18
Figure 4 – Exemple d'affinements de Références avec plusieurs chemins possibles . 19
Figure 5 – Exemple de méthode d'utilisation d'affinements de Références . 19
Figure 6 – Exemple de méthode d'utilisation d'affinements de Références avec deux
niveaux et plusieurs sauts . 20
Figure A.1 – Affinement de Références au moyen d'un Objet Proxy . 24
Tableau 1 – Définition d'IsExecutableOn . 7
Tableau 2 – Définition d'IsExecutingOn . 8
Tableau 3 – Définition de Controls . 8
Tableau 4 – Définition d'Utilizes . 9
Tableau 5 – Définition de Requires . 10
Tableau 6 – Définition d'IsPhysicallyConnectedTo . 11
Tableau 7 – Définition de RepresentsSameEntityAs . 12
Tableau 8 – Définition de RepresentsSameHardwareAs . 13
Tableau 9 – Définition de RepresentsSameFunctionalityAs . 13
Tableau 10 – Définition d'IsHostedBy . 14
Tableau 11 – Définition de HasPhysicalComponent. 15
Tableau 12 – Définition de HasContainedComponent . 16
Tableau 13 – Définition de HasAttachedComponent . 16
Tableau 14 – Définition de ReferenceDescriptionVariableType . 21
Tableau 15 – Définition de HasReferenceDescription . 22
Tableau 16 – Structure de ReferenceDescriptionDataType . 22
Tableau 17 – Définition de ReferenceDescriptionDataType . 22
Tableau 18 – Structure de ReferenceListEntryDataType . 23
Tableau 19 – Définition de ReferenceListEntryDataType . 23
COMMISSION ÉLECTROTECHNIQUE INTERNATIONALE
____________
Architecture unifiée OPC -
Partie 23: ReferenceTypes communs
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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'IEC attire l'attention sur le fait que la mise en application du présent document peut entraîner l'utilisation d'un
ou de plusieurs brevets. L'IEC ne prend pas position quant à la preuve, à la validité et à l'applicabilité de tout
droit de brevet revendiqué à cet égard. À la date de publication du présent document, l'IEC n'avait pas reçu
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L'IEC ne saurait être tenue pour responsable de ne pas avoir identifié tout ou partie de tels droits de brevet.
L'IEC 62541-23 a été établie par le sous-comité 65E: Les dispositifs et leur intégration dans les
systèmes de l'entreprise, du comité d'études 65 de l'IEC: Mesure, commande et automation
dans les processus industriels. Il s'agit d'une Norme internationale.
Le texte de cette Norme internationale est issu des documents suivants:
Projet Rapport de vote
65E/1048/CDV 65E/1105/RVC
Le rapport de vote indiqué dans le tableau ci-dessus donne toute information sur le vote ayant
abouti à son approbation.
La langue employée pour l'élaboration de cette Norme internationale est l'anglais.
Ce document a été rédigé selon les Directives ISO/IEC, Partie 2, il a été développé selon les
Directives ISO/IEC, Partie 1 et les Directives ISO/IEC, Supplément IEC, disponibles sous
www.iec.ch/members_experts/refdocs. Les principaux types de documents développés par
l'IEC sont décrits plus en détail sous www.iec.ch/publications.
Dans l'ensemble du présent document et dans les autres parties de la série, certaines
conventions de document sont utilisées:
Le format italique est utilisé pour mettre en évidence un terme défini ou une définition qui
apparaît à l'article "Termes et définitions" dans l'une des parties de la série.
Le format italique est également utilisé pour mettre en évidence le nom d'un paramètre d'entrée
ou de sortie de service, ou le nom d'une structure ou d'un élément de structure habituellement
défini dans les tableaux.
Par ailleurs, les termes et noms en italique sont souvent écrits en camel-case (pratique qui
consiste à joindre, sans espace, les éléments des mots ou expressions composés, la première
lettre de chaque élément étant en majuscule). Par exemple, le terme défini est AddressSpace
et non Espace d'Adressage. Cela permet de mieux comprendre qu'il existe une définition unique
pour AddressSpace, et non deux définitions distinctes pour Espace et pour Adressage.
Une liste de toutes les parties de la série IEC 62541, publiées sous le titre général Architecture
unifiée OPC, se trouve sur le site web de l'IEC.
Le comité a décidé que le contenu de ce document ne sera pas modifié avant la date de stabilité
indiquée sur le site web de l'IEC sous webstore.iec.ch dans les données relatives au document
recherché. À cette date, le document sera
– reconduit,
– supprimé, ou
– révisé.
1 Domaine d'application
La présente partie de l'IEC 62541 définit les ReferenceTypes communément utilisés dans les
Modèles d'information industriels. Ces ReferenceTypes sont plus spécifiques que ceux de
l'IEC 62541-3 qui font partie intégrante du Modèle d'espace d'adressage OPC UA.
2 Références normatives
Les documents suivants sont cités dans le texte de sorte qu'ils constituent, pour tout ou partie
de leur contenu, des exigences du présent document. Pour les références datées, seule
l'édition citée s'applique. Pour les références non datées, la dernière édition du document de
référence s'applique (y compris les éventuels amendements).
IEC 62541-1, Architecture unifiée OPC - Partie 1: Vue d'ensemble et concepts
IEC 62541-3, Architecture unifiée OPC - Partie 3: Modèle d'espace d'adressage
IEC 62541-5, Architecture unifiée OPC - Partie 5: Modèle d'information
3 Termes, définitions et abréviations
3.1 Termes et définitions
Pour les besoins du présent document, les termes et définitions de l'IEC 62541-1,
l'IEC 62541-3, et l'IEC 62541-5 s'appliquent.
L'ISO et l'IEC tiennent à jour des bases de données terminologiques destinées à être utilisées
en normalisation, consultables aux adresses suivantes:
– IEC Electropedia: disponible à l'adresse https://www.electropedia.org/
– ISO Online browsing platform: disponible à l'adresse https://www.iso.org/obp
3.2 Abréviations
CPU (Central Processing Unit) Unité centrale de traitement
E/S Entrée/Sortie
IP (Internet Protocol) Protocole Internet
PC (Personal Computer) Ordinateur personnel
PCI (Peripheral Component Interconnect) Interconnexion de composants périphériques
PHY Couche physique
PLC (Programmable Logic Controller) Automate programmable
RFID (Radio Frequency Identification) Identification par radiofréquence
4 ReferenceTypes OPC UA
4.1 Vue d'ensemble
La Figure 1 offre une vue d'ensemble des ReferenceTypes définis dans les paragraphes
suivants.
Figure 1 – Vue d'ensemble des ReferenceTypes
4.2 IsExecutableOn
4.2.1 Vue d'ensemble
Ce ReferenceType peut être utilisé pour exposer la relation entre un composant logiciel et son
environnement d'exécution. Par exemple, il peut être utilisé pour révéler quel micrologiciel (y
compris sa version) est disponible sur un appareil de terrain.
4.2.2 Définition
IsExecutableOn est un ReferenceType concret qui peut être utilisé directement. Il s'agit d'un
sous-type des NonHierarchicalReferences.
La sémantique de ce ReferenceType a pour objet de relier un composant logiciel à son
environnement d'exécution requis pour le fonctionnement du logiciel (par exemple, un
composant matériel, une tâche ou un fil). La relation montre que l'environnement d'exécution
vers lequel pointe la référence est capable d'exécuter le composant logiciel. Cela ne signifie
pas que le composant logiciel est actuellement en cours d'exécution ou en fonctionnement.
Pour montrer que le logiciel fonctionne dans un environnement, il convient d'utiliser
IsExecutingOn.
Le SourceNode des Références de ce ReferenceType doit être un Objet ou un ObjectType
représentant un composant logiciel.
Le TargetNode des Références de ce ReferenceType doit être un Objet ou un ObjectType
représentant un environnement d'exécution pour un composant logiciel, qui peut être un
élément matériel (par exemple un dispositif) ou un autre environnement tel qu'une tâche, un fil
d'exécution ou un cadre d'exécution de logiciel.
IsExecutableOn est défini de manière formelle dans le Tableau 1.
Tableau 1 – Définition d'IsExecutableOn
Attributs Valeur
BrowseName IsExecutableOn
InverseName CanExecute
Symmetric FALSE
IsAbstract FALSE
Références NodeClass BrowseName Commentaire
Sous-type de NonHierarchicalReferences défini dans l'IEC 62541-5
Unités de Conformité
Informations de base IsExecutableOn
4.3 IsExecutingOn
4.3.1 Vue d'ensemble
Ce ReferenceType peut être utilisé pour indiquer la relation entre un composant logiciel et
l'environnement d'exécution dans lequel il est actuellement exécuté. Les Références de ce
ReferenceType peuvent être très dynamiques et disparaîtront dès que le composant logiciel
n'est plus exécuté. Il peut par exemple être utilisé pour montrer qu'un programme d'automate
programmable (Programmable Logic Controller, PLC) est en cours d'exécution sur une tâche
spécifique d'un PLC.
4.3.2 Définition
IsExecutingOn est un ReferenceType concret qui peut être utilisé directement. Il s'agit d'un
sous-type d'Utilizes.
La sémantique de ce ReferenceType a pour objet de relier un composant logiciel à
l'environnement d'exécution dans lequel il est actuellement exécuté (par exemple, un
composant matériel, une tâche ou un fil). Les Références de ce ReferenceType doivent être
utilisées uniquement lorsque le composant logiciel est en cours d'exécution/de fonctionnement.
Le SourceNode des Références de ce ReferenceType doit être un Objet ou un ObjectType
représentant un composant logiciel.
Le TargetNode des Références de ce ReferenceType doit être un Objet ou un ObjectType
représentant un environnement d'exécution pour un composant logiciel, qui peut être un
élément matériel (par exemple un dispositif) ou un autre environnement tel qu'une tâche, un fil
d'exécution ou un cadre d'exécution de logiciel.
IsExecutingOn est défini de manière formelle dans le Tableau 2.
Tableau 2 – Définition d'IsExecutingOn
Attributs Valeur
BrowseName IsExecutingOn
InverseName Executes
Symmetric FALSE
IsAbstract FALSE
Références NodeClass BrowseName Commentaire
Sous-type de Utilizes défini au 4.5
Unités de Conformité
Informations de base IsExecutingOn
4.4 Controls
4.4.1 Vue d'ensemble
Ce ReferenceType peut être utilisé pour exposer la relation entre un objet qui commande
d'autres objets et les objets commandés. Par exemple, il peut être utilisé pour relier un PLC
aux dispositifs de terrain ou aux modules de machine commandés par le PLC, ou un composant
logiciel aux composants matériels commandés par le composant logiciel.
4.4.2 Définition
Controls est un ReferenceType concret qui peut être utilisé directement. Il s'agit d'un sous-type
des HierarchicalReferences.
La sémantique de ce ReferenceType a pour objet de relier le composant de commande aux
composants commandés par le composant de commande.
Le SourceNode des Références de ce ReferenceType doit être un Objet ou un ObjectType
représentant le composant de commande, par exemple un PLC ou un composant logiciel.
Le TargetNode des Références de ce ReferenceType doit être un Objet représentant un
composant qui est commandé par le TargetNode.
Controls est défini de manière formelle dans le Tableau 3.
Tableau 3 – Définition de Controls
Attributs Valeur
BrowseName Controls
InverseName IsControlledBy
Symmetric FALSE
IsAbstract FALSE
Références NodeClass BrowseName Commentaire
Sous-type de HierarchicalReferences défini dans l'IEC 62541-5
Unités de Conformité
Informations de base Controls
4.5 Utilizes
4.5.1 Vue d'ensemble
Ce ReferenceType peut être utilisé pour exposer la relation entre un composant et d'autres
composants nécessaires à son fonctionnement. Contrairement au ReferenceType Requires, ce
ReferenceType non hiérarchique autorise les boucles, par exemple lorsque les deux
composants ont besoin l'un de l'autre pour fonctionner. Dans ce cas, il y aurait deux
Références, la première pointant d'un composant vers l'autre, et inversement pour la seconde.
Par exemple, le ventilateur d'un PC a besoin de l'alimentation électrique pour fonctionner et
l'alimentation électrique a besoin du refroidissement assuré par le ventilateur pour ne pas
surchauffer. Un robot utilisant un système de vision pour déterminer la position à laquelle il doit
saisir un objet est un exemple d'utilisation sans boucle.
4.5.2 Définition
Utilizes est un ReferenceType concret qui peut être utilisé directement. Il s'agit d'un sous-type
des NonHierarchicalReferences.
La sémantique de ce ReferenceType a pour objet de relier un composant à d'autres composants
nécessaires à son fonctionnement.
Le SourceNode des Références de ce ReferenceType doit être un Objet ou un ObjectType
représentant un composant qui utilise le TargetNode pour fonctionner.
Le TargetNode des Références de ce ReferenceType doit être un Objet ou un ObjectType
représentant le composant exigé.
Requires est défini de manière formelle dans le Tableau 4.
Tableau 4 – Définition d'Utilizes
Attributs Valeur
BrowseName Utilizes
InverseName IsUtilizedBy
Symmetric FALSE
IsAbstract FALSE
Références NodeClass BrowseName Commentaire
Sous-type de NonHierarchicalReferences défini dans l'IEC 62541-5
Unités de Conformité
Informations de base Utilizes
4.6 Requires
4.6.1 Vue d'ensemble
Ce ReferenceType peut être utilisé pour exposer la relation entre un composant et d'autres
composants exigés pour son fonctionnement. Contrairement au ReferenceType
HasComponent, les composants connexes ne sont pas considérés comme des sous-
composants du composant. Contrairement au ReferenceType Utilizes, ce ReferenceType
hiérarchique présente une hiérarchie de dépendances sans boucle.
Il peut par exemple être utilisé pour relier un axe d'un dispositif mobile aux groupes
motopropulseurs exigés ou un composant logiciel à d'autres composants logiciels exigés pour
l'exécution du composant logiciel, par exemple des bibliothèques.
4.6.2 Définition
Requires est un ReferenceType concret qui peut être utilisé directement. Il s'agit d'un sous-
type des Hier
...
IEC 62541-23 ®
Edition 1.0 2025-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
OPC unified architecture -
Part 23: Common ReferenceTypes
Architecture unifiée OPC -
Partie 23: ReferenceTypes communs
ICS 25.040 ISBN 978-2-8327-0837-8
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CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms, definitions and abbreviated terms . 5
3.1 Terms and definitions . 5
3.2 Abbreviated terms. 5
4 OPC UA ReferenceTypes . 5
4.1 Overview . 5
4.2 IsExecutableOn . 6
4.2.1 Overview . 6
4.2.2 Definition . 6
4.3 IsExecutingOn . 7
4.3.1 Overview . 7
4.3.2 Definition . 7
4.4 Controls . 8
4.4.1 Overview . 8
4.4.2 Definition . 8
4.5 Utilizes . 9
4.5.1 Overview . 9
4.5.2 Definition . 9
4.6 Requires . 9
4.6.1 Overview . 9
4.6.2 Definition . 10
4.7 IsPhysicallyConnectedTo. 10
4.7.1 Overview . 10
4.7.2 Definition . 10
4.8 RepresentsSameEntityAs . 11
4.8.1 Overview . 11
4.8.2 Definition . 11
4.9 RepresentsSameHardwareAs . 12
4.9.1 Overview . 12
4.9.2 Definition . 12
4.10 RepresentsSameFunctionalityAs . 13
4.10.1 Overview . 13
4.10.2 Definition . 13
4.11 IsHostedBy . 14
4.11.1 Overview . 14
4.11.2 Definition . 14
4.12 HasPhysicalComponent. 14
4.12.1 Overview . 14
4.12.2 Definition . 15
4.13 HasContainedComponent . 15
4.13.1 Overview . 15
4.13.2 Definition . 15
4.14 HasAttachedComponent . 16
4.14.1 Overview . 16
4.14.2 Definition . 16
5 Reference Description . 17
5.1 Overview . 17
5.2 Reference refinement . 18
5.3 OPC UA VariableTypes . 20
5.3.1 Overview . 20
5.3.2 ReferenceDescriptionVariableType . 20
5.4 OPC UA ReferenceTypes . 20
5.4.1 Overview . 20
5.4.2 HasReferenceDescription . 20
5.5 OPC UA DataTypes . 21
5.5.1 ReferenceDescriptionDataType . 21
5.5.2 ReferenceListEntryDataType . 22
Annex A (informative) ReferenceDescription Design Decisions . 23
A.1 Overview . 23
A.2 Alternative Approach: Intermediate Object. 23
Bibliography . 24
Figure 1 – Overview of ReferenceTypes . 6
Figure 2 – Example of ReferenceDescriptions . 17
Figure 3 – Examples of Reference refinements . 18
Figure 4 – Example of Reference refinements with multiple path options . 18
Figure 5 – Example of how to use Reference refinements . 19
Figure 6 – Example of how to use Reference refinements with two levels and multiple
hops. 19
Figure A.1 – Refinement of References by Proxy Object . 23
Table 1 – IsExecutableOn definition . 7
Table 2 – IsExecutingOn definition . 8
Table 3 – Controls definition . 8
Table 4 – Utilizes definition . 9
Table 5 – Requires definition . 10
Table 6 – IsPhysicallyConnectedTo definition . 11
Table 7 – RepresentsSameEntityAs definition . 12
Table 8 – RepresentsSameHardwareAs definition . 13
Table 9 – RepresentsSameFunctionalityAs definition . 13
Table 10 – IsHostedBy definition . 14
Table 11 – HasPhysicalComponent definition . 15
Table 12 – HasContainedComponent definition . 16
Table 13 – HasAttachedComponent definition . 16
Table 14 – ReferenceDescriptionVariableType definition . 20
Table 15 – HasReferenceDescription definition . 21
Table 16 – ReferenceDescriptionDataType structure . 21
Table 17 – ReferenceDescriptionDataType definition . 22
Table 18 – ReferenceListEntryDataType structure . 22
Table 19 – ReferenceListEntryDataType definition . 22
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
OPC unified architecture -
Part 23: Common ReferenceTypes
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
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shall not be held responsible for identifying any or all such patent rights.
IEC 62541-23 has been prepared by subcommittee 65E: Devices and integration in enterprise
systems, of IEC technical committee 65: Industrial-process measurement, control, and
automation. It is an International Standard.
The text of this International Standard is based on the following documents:
Draft Report on voting
65E/1048/CDV 65E/1105/RVC
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/publications.
Throughout this document and the other Parts of the series, certain document conventions are
used:
Italics are used to denote a defined term or definition that appears in the "Terms and definitions"
clause in one of the parts of the series.
Italics are also used to denote the name of a service input or output parameter or the name of
a structure or element of a structure that are usually defined in tables.
The italicized terms and names are also often written in camel-case (the practice of writing
compound words or phrases in which the elements are joined without spaces, with each
element's initial letter capitalized within the compound). For example, the defined term is
AddressSpace instead of Address Space. This makes it easier to understand that there is a
single definition for AddressSpace, not separate definitions for Address and Space.
A list of all parts of the IEC 62541 series, published under the general title OPC Unified
Architecture, can be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
– reconfirmed,
– withdrawn, or
– revised.
1 Scope
This part of IEC 62541 defines ReferenceTypes commonly used in industrial Information
Models. They are more specific than the ReferenceTypes in IEC 62541-3 which are an inherent
part of the OPC UA Address Space Model.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies.
For undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 62541-1, OPC Unified Architecture - Part 1: Overview and Concepts
IEC 62541-3, OPC Unified Architecture - Part 3: Address Space Model
IEC 62541-5, OPC Unified Architecture - Part 5: Information Model
3 Terms, definitions and abbreviated terms
3.1 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 62541-1,
IEC 62541-3, and IEC 62541-5 apply.
ISO and IEC maintain terminology databases for use in standardization at the following
addresses:
– IEC Electropedia: available at https://www.electropedia.org/
– ISO Online browsing platform: available at https://www.iso.org/obp
3.2 Abbreviated terms
CPU Central Processing Unit
IO Input/Output
IP Internet Protocol
PC Personal Computer
PCI Peripheral Component Interconnect
PHY Physical Layer
PLC Programmable Logic Controller
RFID Radio Frequency Identification
4 OPC UA ReferenceTypes
4.1 Overview
Figure 1 gives an overview of the ReferenceTypes defined in the following subsections.
Figure 1 – Overview of ReferenceTypes
4.2 IsExecutableOn
4.2.1 Overview
This ReferenceType can be used to expose the relation between a software component and its
execution environment. For example, it can be used to expose which firmware (including its
version) is available on a field device.
4.2.2 Definition
The IsExecutableOn is a concrete ReferenceType and can be used directly. It is a subtype of
NonHierarchicalReferences.
The semantic of this ReferenceType is to relate a software component to its execution
environment that is required to run the software (e.g. Hardware component, Task or Thread).
The relationship shows that the execution environment the reference points to, is able to
execute the software component. This does not imply that the software component is currently
being executed or running. To show that the software is running in an environment,
IsExecutingOn should be used.
The SourceNode of References of this ReferenceType shall be an Object or ObjectType
representing a software component.
The TargetNode of References of this ReferenceType shall be an Object or ObjectType
representing an execution environment for a software component, which can be a piece of
hardware (e.g. Device) or some other environment like a task, thread, or software execution
framework.
IsExecutableOn is formally defined in Table 1.
Table 1 – IsExecutableOn definition
Attributes Value
BrowseName IsExecutableOn
InverseName CanExecute
Symmetric FALSE
IsAbstract FALSE
References NodeClass BrowseName Comment
Subtype of NonHierarchicalReferences defined in IEC 62541-5
Conformance Units
Base Info IsExecutableOn
4.3 IsExecutingOn
4.3.1 Overview
This ReferenceType can be used to expose the relation between a software component and its
execution environment it is currently executing on. References of this ReferenceType can be
very dynamic and will disappear as soon as the software component is not being executed
anymore. For example, it can be used to expose that a PLC program is currently running on a
specific task of a PLC.
4.3.2 Definition
The IsExecutingOn is a concrete ReferenceType and can be used directly. It is a subtype of
Utilizes.
The semantic of this ReferenceType is to relate a software component to its execution
environment it is currently executing on (e.g. Hardware component, Task or Thread).
References of this ReferenceType shall only be used when the software component is currently
executed / running.
The SourceNode of References of this ReferenceType shall be an Object or ObjectType
representing a software component.
The TargetNode of References of this ReferenceType shall be an Object or ObjectType
representing an execution environment for a software component, which can be a piece of
hardware (e.g. Device) or some other environment like a task, thread or software execution
framework.
IsExecutingOn is formally defined in Table 2.
Table 2 – IsExecutingOn definition
Attributes Value
BrowseName IsExecutingOn
InverseName Executes
Symmetric FALSE
IsAbstract FALSE
References NodeClass BrowseName Comment
Subtype of Utilizes defined in 4.5
Conformance Units
Base Info IsExecutingOn
4.4 Controls
4.4.1 Overview
This ReferenceType can be used to expose the relation between an object controlling other
objects and the controlled objects. For example, it can be used to relate a PLC to the field
devices or machine-modules controlled by the PLC or a software component to the hardware
components controlled by the software component.
4.4.2 Definition
The Controls is a concrete ReferenceType and can be used directly. It is a subtype of
HierarchicalReferences.
The semantic of this ReferenceType is to relate the controlling component to the components
controlled by the controlling component.
The SourceNode of References of this ReferenceType shall be an Object or ObjectType
representing the controlling component, as for example a PLC or a software component.
The TargetNode of References of this ReferenceType shall be an Object representing a
component that is controlled by the TargetNode.
Controls is formally defined in Table 3.
Table 3 – Controls definition
Attributes Value
BrowseName Controls
InverseName IsControlledBy
Symmetric FALSE
IsAbstract FALSE
References NodeClass BrowseName Comment
Subtype of HierarchicalReferences defined in IEC 62541-5
Conformance Units
Base Info Controls
4.5 Utilizes
4.5.1 Overview
This ReferenceType can be used to expose the relation between a component to other
components, that the component needs in order to work. In contrast to the Requires
ReferenceType, this non-hierarchical ReferenceType allows loops, e.g. both components need
each other in order to work. In that case, there would be two References, the first one pointing
from one component to the other, and the second one vice versa. For example, a fan in a PC
needs the power supply in order to work and the power supply needs the cooling from the fan,
that it is not overheating. An example of a non-looping usage is that a robot utilizes a vision
system in order to get the position where to grab something.
4.5.2 Definition
The Utilizes is a concrete ReferenceType and can be used directly. It is a subtype of
NonHierarchicalReferences.
The semantic of this ReferenceType is to relate a component to other components that are
needed by the component in order to work.
The SourceNode of References of this ReferenceType shall be an Object or ObjectType
representing a component that utilizes the TargetNode in order to work.
The TargetNode of References of this ReferenceType shall be an Object or ObjectType
representing the required component.
Requires is formally defined in Table 4.
Table 4 – Utilizes definition
Attributes Value
BrowseName Utilizes
InverseName IsUtilizedBy
Symmetric FALSE
IsAbstract FALSE
References NodeClass BrowseName Comment
Subtype of NonHierarchicalReferences defined in IEC 62541-5
Conformance Units
Base Info Utilizes
4.6 Requires
4.6.1 Overview
This ReferenceType can be used to expose the relation between a component to other
components, that the component requires in order to work. In contrast to the HasComponent
ReferenceType, the related components are not considered to be subcomponents of the
component. In contrast to the Utilizes ReferenceType, this hierarchical ReferenceType exposes
a non-looping hierarchy of dependencies.
For example, it can be used to relate an axis of a motion device to its required powertrains or
a software component to other software components required to execute the software
component, like for example libraries.
4.6.2 Definition
The Requires is a concrete ReferenceType and can be used directly. It is a subtype of
HierarchicalReferences.
The semantic of this ReferenceType is to relate a component to other components it requires
in order to work.
The SourceNode of References of this ReferenceType shall be an Object or ObjectType
representing a component that requires the TargetNode in order to work.
The TargetNode of References of this ReferenceType shall be an Object representing the
required component used by the SourceNode.
Requires References shall not lead to loops, that is, starting from Node "A" and only following
References of ReferenceType Requires or subtypes it shall never be possible to return to "A".
But it is allowed that following the References there can be more than one path leading to
another Node "B".
Requires is formally defined in Table 5.
Table 5 – Requires definition
Attributes Value
BrowseName Requires
InverseName IsRequiredBy
Symmetric FALSE
IsAbstract FALSE
References NodeClass BrowseName Comment
Subtype of HierarchicalReferences defined in IEC 62541-5
Conformance Units
Base Info Requires
4.7 IsPhysicallyConnectedTo
4.7.1 Overview
This ReferenceType can be used to expose the relation between two hardware components
which are mounted or mechanically linked or connected to each other, without one component
being a subcomponent of the other component. If one component is considered to be a
subcomponent, the HasAttachedComponent ReferenceType should be used. For example, it
can be used to relate a motor to a gear.
4.7.2 Definition
The IsPhysicallyConnectedTo is a concrete ReferenceType and can be used directly. It is a
subtype of NonHierarchicalReferences. It is a symmetric Reference, that is, it provides the same
semantic in both directions.
The semantic of this ReferenceType is to connect two hard components that are physically
connected, without one being a subcomponent of the other.
The SourceNode of References of this type shall be an Object or ObjectType representing a
piece of hardware.
The TargetNode of this ReferenceType shall be an Object representing a piece of hardware.
IsPhysicallyConnectedTo is formally defined in Table 6.
Table 6 – IsPhysicallyConnectedTo definition
Attributes Value
BrowseName IsPhysicallyConnectedTo
InverseName -
Symmetric TRUE
IsAbstract FALSE
References NodeClass BrowseName Comment
Subtype of NonHierarchicalReferences defined in IEC 62541-5
Conformance Units
Base Info IsPhysicallyConnectedTo
4.8 RepresentsSameEntityAs
4.8.1 Overview
This ReferenceType can be used to expose that two different Nodes in the AddressSpace
representing the same entity in the real world. Both Nodes can represent different aspects of
the same entity in the same world, or model the same aspect in different ways, for example
defined in different companion specifications. For example, an ethernet port of a network
module can be represented as an Object of an ObjectType defined by one companion
specification focusing on the PROFINET relevant information for such a port and by another
Object providing a more generic Ethernet and IP focused view on the port defined by an
ObjectType in another companion specification. Both Objects can have distinguished
information, but also provide some common information like the IP address, potentially in
different data formats.
If a Server exposes more than two Nodes representing the same entity, it is recommended that
all of the Nodes reference each other. A Client should not rely on all Nodes being mutually
referenced to each other; i.e., the Client should browse each of the Nodes checking for
additional RepresentsSameEntityAs References.
4.8.2 Definition
The RepresentsSameEntityAs is a concrete ReferenceType and can be used directly. It is a
subtype of NonHierarchicalReferences. It is a symmetric Reference, that is, it provides the same
semantic in both directions.
The semantic of this ReferenceType is to relate two Nodes that represent the same entity in the
real world.
The SourceNode of References of this ReferenceType can be of any NodeClass.
The TargetNode of References of this ReferenceType can be of any NodeClass.
Both, SourceNode and TargetNode shall represent the same entity in the real world.
RepresentsSameEntityAs is formally defined in Table 7.
Table 7 – RepresentsSameEntityAs definition
Attributes Value
BrowseName RepresentsSameEntityAs
InverseName -
Symmetric TRUE
IsAbstract FALSE
References NodeClass BrowseName Comment
Subtype of NonHierarchicalReferences defined in IEC 62541-5
Conformance Units
Base Info RepresentsSameEntityAs
4.9 RepresentsSameHardwareAs
4.9.1 Overview
This ReferenceType can be used to expose that two different Nodes in the AddressSpace
representing the same hardware. It refines the RepresentsSameEntityAs ReferenceType and
defines that the same entity in the real world shall be a piece of hardware. For example, it can
be used to relate an Object representing a RFID reader based on the AutoID companion
specification [1] with an Object representing the same RFID reader based on the IO-Link
companion specification [2].
NOTE The example given above is special since both specifications use IEC 62541-100, Device Model [3] as base.
In this case, the preferred modelling approach is provided in an annex of Part 100, where a composition approach is
used.
4.9.2 Definition
The RepresentsSameHardwareAs is a concrete ReferenceType and can be used directly. It is
a subtype of HierarchicalReferences. It is a symmetric Reference, that is, it provides the same
semantic in both directions
The semantic of this ReferenceType is to relate two Nodes that represent the same hardware.
The SourceNode of References of this ReferenceType can be of any NodeClass.
The TargetNode of References of this ReferenceType can be of any NodeClass.
Both, SourceNode and TargetNode shall represent the same entity in the real world.
RepresentsSameHardwareAs is formally defined in Table 8.
___________
Numbers in square brackets refer to the Bibliography.
Table 8 – RepresentsSameHardwareAs definition
Attributes Value
BrowseName RepresentsSameHardwareAs
InverseName -
Symmetric TRUE
IsAbstract FALSE
References NodeClass BrowseName Comment
Subtype of RepresentsSameEntityAs defined in 4.8
Conformance Units
Base Info RepresentsSameHardwareAs
4.10 RepresentsSameFunctionalityAs
4.10.1 Overview
This ReferenceType can be used to expose that two different Nodes in the AddressSpace
representing the same functionality. It refines the RepresentsSameEntityAs ReferenceType and
defines that the same entity in the real world shall be a functionality. For example, the
functionality to move an axis can be provided by an Object representing a function block of a
PLC with that functionality, but also be an Object representing the functionality of a drive. The
ReferenceType can be used to related both Objects.
4.10.2 Definition
The RepresentsSameFunctionalityAs is a concrete ReferenceType and can be used directly. It
is a subtype of HierarchicalReferences. It is a symmetric Reference, that is, it provides the
same semantic in both directions.
The semantic of this ReferenceType is to relate two Nodes that represent the same functionality.
The SourceNode of References of this ReferenceType can be of any NodeClass.
The TargetNode of References of this ReferenceType can be of any NodeClass.
Both, SourceNode and TargetNode shall represent the same functionality.
RepresentsSameFunctionalityAs is formally defined in Table 9.
Table 9 – RepresentsSameFunctionalityAs definition
Attributes Value
BrowseName RepresentsSameFunctionalityAs
InverseName -
Symmetric TRUE
IsAbstract FALSE
References NodeClass BrowseName Comment
Subtype of RepresentsSameEntityAs defined in 4.8
Conformance Units
Base Info RepresentsSameFunctionalityAs
4.11 IsHostedBy
4.11.1 Overview
This ReferenceType can be used to expose the relation between an Object representing some
functionality and an Object representing some environment (e.g. hard- or software) which is
necessary to execute and run the functionality. This implies that a malfunction in a referred
environment or a missing related environment results in a non-functional functionality. A
functionality Object can relate to several environment Objects, in that case all environment
Objects are necessary to execute and run the functionality. An environment Object can be
referenced by several functionality Objects.
For example, the functionality to move an axis is hosted by the drive moving the axis. Another
example is some analog input functionality, which is related to the IO-module and the related
firmware.
4.11.2 Definition
The IsHostedBy is a concrete ReferenceType and can be used directly. It is a subtype of
Utilizes.
The semantic of this ReferenceType is to relate functionality represented by an OPC UA Node
to the hard- and software needed to provide the functionality.
The SourceNode of References of this ReferenceType shall be an Object or ObjectType
representing some functionality.
The TargetNode of References of this ReferenceType shall be an Object or ObjectType
representing some hard- or software.
IsHostedBy is formally defined in Table 10.
Table 10 – IsHostedBy definition
Attributes Value
BrowseName IsHostedBy
InverseName Hosts
Symmetric FALSE
IsAbstract FALSE
References NodeClass BrowseName Comment
Subtype of Utilizes defined in 4.5
Conformance Units
Base Info IsHostedBy
4.12 HasPhysicalComponent
4.12.1 Overview
This ReferenceType can be used to expose the relation between a hardware component and
its subcomponent. An example for this reference is a modular IO-Station which is composed
out of a device head and multiple IO-Modules or it can be used to relate a PC to a PCI board
plugged inside the PC.
4.12.2 Definition
The HasPhysicalComponent is a concrete ReferenceType and can be used directly. It is a
subtype of HasComponent.
The semantic of this ReferenceType is to relate a hardware component to its subcomponent,
which is also a hardware component.
The SourceNode of References of this ReferenceType shall be an Object or ObjectType
representing a piece of hardware.
The TargetNode of References of this ReferenceType shall be an Object representing a piece
of hardware that is a component of the SourceNode.
HasPhysicalComponent is formally defined in Table 11.
Table 11 – HasPhysicalComponent definition
Attributes Value
BrowseName HasPhysicalComponent
InverseName PhysicalComponentOf
Symmetric FALSE
IsAbstract FALSE
References NodeClass BrowseName Comment
Subtype of HasComponent defined in IEC 62541-5
Conformance Units
Base Info HasPhysicalComponent
4.13 HasContainedComponent
4.13.1 Overview
This ReferenceType can be used to expose the relation between a hardware component and
its subcomponent. It indicates that the subcomponent is inside the component. To gain access
to the subcomponent typically removing a part of the component (e.g. a hatch) is necessary.
For example, it can be used to relate a PC to a PCI board plugged inside the PC. The PCI board
is accessible after removing the PC housing. It can also be used to relate a PLC to its CPU,
which is hard wired to the PLC, or a network module to its Ethernet PHYs.
4.13.2 Definition
The HasContainedComponent is a concrete ReferenceType and can be used directly. It is a
subtype of HasPhysicalComponent.
The semantic of this ReferenceType is to relate a hardware component to its subcomponent
that is inside the component.
The SourceNode of References of this ReferenceType shall be an Object or ObjectType
representing a piece of hardware.
The TargetNode of References of this ReferenceType shall be an Object representing a piece
of hardware that is a component of the SourceNode.
HasContainedComponent is formally defined in Table 12.
Table 12 – HasContainedComponent definition
Attributes Value
BrowseName HasContainedComponent
InverseName ContainedComponentOf
Symmetric FALSE
IsAbstract FALSE
References NodeClass BrowseName Comment
Subtype of HasPhysicalComponent defined in 4.12
Conformance Units
Base Info HasContainedComponent
4.14 HasAttachedComponent
4.14.1 Overview
This ReferenceType can be used to expose the relation between a hardware component and
its subcomponent. It indicates that the subcomponent is attached to the component. That
implies that the subcomponent is located in direct contact or direct vicinity of the component
and is visible from the outside of the component without removing parts of the component (like
a hatch). For example, it can be used to relate a drive device or a modular IO-station which is
composed out of a device head and multiple IO-modules attached to the head to such an IO-
module like a fieldbus interface module. Another example is a laptop having a removable battery
attached to it.
4.14.2 Definition
The HasAttachedComponent is a concrete ReferenceType and can be used directly. It is a
subtype of HasPhysicalComponent.
The semantic of this ReferenceType is to relate a hardware component to its subcomponent
that is attached to the component.
The SourceNode of References of this ReferenceType shall be an Object or ObjectType
representing a piece of hardware.
The TargetNode of References of this ReferenceType shall be an Object representing a piece
of hardware that is a component of the SourceNode.
HasAttachedComponent is formally defined in Table 13.
Table 13 – HasAttachedComponent defin
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