prEN IEC 62541-23:2024

SLOVENSKI STANDARD
01-marec-2024
Enotna arhitektura OPC - 23. del: Skupni tipi zvez
OPC unified architecture - Part 23: Common reference types
Ta slovenski standard je istoveten z: prEN IEC 62541-23:2024
ICS:
25.040.40 Merjenje in krmiljenje Industrial process
industrijskih postopkov measurement and control
35.240.50 Uporabniške rešitve IT v IT applications in industry
industriji
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

65E/1048/CDV
COMMITTEE DRAFT FOR VOTE (CDV)
PROJECT NUMBER:
IEC 62541-23 ED1
DATE OF CIRCULATION: CLOSING DATE FOR VOTING:
2024-01-26 2024-04-19
SUPERSEDES DOCUMENTS:
65E/958/NP, 65E/1018/RVN
IEC SC 65E : DEVICES AND INTEGRATION IN ENTERPRISE SYSTEMS
SECRETARIAT: SECRETARY:
United States of America Mr Donald (Bob) Lattimer
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TITLE:
OPC Unified Architecture – Part 23: Common ReferenceTypes

PROPOSED STABILITY DATE: 2026
NOTE FROM TC/SC OFFICERS:
electronic file, to make a copy and to print out the content for the sole purpose of preparing National Committee positions.
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1 IEC CDV 62541-23 © IEC 2023
1 CONTENTS
2 Page
4 1 Scope . 1
5 2 Normative references . 1
6 3 Terms, definitions, abbreviated terms, and conventions . 1
7 Terms and definitions . 1
8 Abbreviated terms . 1
9 4 OPC UA ReferenceTypes . 2
10 Overview . 2
11 IsExecutableOn . 2
12 Overview . 2
13 Definition . 2
14 IsExecutingOn . 3
15 Overview . 3
16 Definition . 3
17 Controls . 3
18 Overview . 3
19 Definition . 3
20 Utilizes . 4
21 Overview . 4
22 Definition . 4
23 Requires . 5
24 Overview . 5
25 Definition . 5
26 IsPhysicallyConnectedTo . 5
27 Overview . 5
28 Definition . 5
29 RepresentsSameEntityAs . 6
30 Overview . 6
31 Definition . 6
32 RepresentsSameHardwareAs . 7
33 Overview . 7
34 Definition . 7
35 RepresentsSameFunctionalityAs . 7
36 Overview . 7
37 Definition . 7
38 IsHostedBy . 8
39 Overview . 8
40 Definition . 8
41 HasPhysicalComponent . 8
42 Overview . 8
43 Definition . 9
44 HasContainedComponent . 9
45 Overview . 9
46 Definition . 9
47 HasAttachedComponent . 10
48 Overview . 10
49 Definition . 10

2 IEC CDV 62541-23 © IEC 2023
50 5 Reference Description . 10
51 Overview . 10
52 Reference Refinement . 12
53 OPC UA VariableTypes. 14
54 ReferenceDescriptionVariableType . 14
55 OPC UA ReferenceTypes . 14
56 HasReferenceDescription . 14
57 OPC UA DataTypes . 15
58 ReferenceDescriptionDataType . 15
59 ReferenceListEntryDataType . 15
60 Annex A (Informative) ReferenceDescription Design Decisions . 16
61 A.1 Overview . 16
62 A.2 Alternative Approach: Intermediate Object . 16
63 Bibliography . 17
3 IEC CDV 62541-23 © IEC 2023
66 Figures
68 Figure 1 – Overview of ReferenceTypes . 2
Figure 2 – Example of ReferenceDescriptions . 11
70 Figure 3 – Examples of Reference Refinements . 12
Figure 4 – Example of Reference Refinements with multiple path options . 12
72 Figure 5 – Example of how to use Reference Refinements . 13
Figure 6 – Example of how to use Reference Refinements with two Levels and Multiple Hops13
74 Figure A.1 – Refinement of References by Proxy Object . 16
4 IEC CDV 62541-23 © IEC 2023
77 Tables
78 Table 1 – IsExecutableOn Definition . 3
79 Table 2 – IsExecutingOn Definition . 3
80 Table 3 – Controls Definition . 4
81 Table 4 – Utilizes Definition . 4
82 Table 5 – Requires Definition . 5
83 Table 6 – IsPhysicallyConnectedTo Definition . 6
84 Table 7 – RepresentsSameEntityAs Definition . 6
85 Table 8 – RepresentsSameHardwareAs Definition. 7
86 Table 9 – RepresentsSameFunctionalityAs Definition . 8
87 Table 10 – IsHostedBy Definition . 8
88 Table 11 – HasPhysicalComponent Definition . 9
89 Table 12 – HasContainedComponent Definition. 10
90 Table 13 – HasAttachedComponent Definition . 10
91 Table 14 – ReferenceDescriptionVariableType Definition . 14
92 Table 15 – HasReferenceDescription Definition . 14
93 Table 16 – ReferenceDescriptionDataType Structure . 15
94 Table 17 – ReferenceDescriptionDataType Definition . 15
95 Table 18 – ReferenceListEntryDataType Structure . 15
96 Table 19 – ReferenceListEntryDataType Definition . 15
5 IEC CDV 62541-23 © IEC 2023
99 INTERNATIONAL ELECTROTECHNICAL COMMISSION
100 ____________
102 OPC UNIFIED ARCHITECTURE –
104 Part 23: Common ReferenceTypes
106 FOREWORD
107 1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising all
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112 committees; any IEC National Committee interested in the subject dealt with may participate in this preparatory work.
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115 determined by agreement between the two organizations.
116 2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
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132 publication, use of, or reliance upon, this IEC Publication or any other IEC Publications.
133 8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is indispensable
134 for the correct application of this publication.
135 9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of patent rights.
136 IEC shall not be held responsible for identifying any or all such patent rights.
137 The main task of IEC technical committees is to prepare International Standards. However, a technical
138 committee may propose the publication of a technical report when it has collected data of a different
139 kind from that which is normally published as an International Standard, for example "state of the art".
140 International Standard IEC 62541-23 has been prepared by subcommittee 65E: Devices and
141 integration in enterprise systems, of IEC technical committee 65: Industrial-process measurement,
142 control, and automation.
143 The text of this international standard is based on the following documents:
CDV Report on voting
65E/XX/CDV 65E/XX/RVC
145 Full information on the voting for the approval of this international standard can be found in the report
146 on voting indicated in the above table.
147 This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
148 Throughout this document and the other Parts of the series, certain document conventions are used:

6 IEC CDV 62541-23 © IEC 2023
149 Italics are used to denote a defined term or definition that appears in the “Terms and definition” clause
150 in one of the parts of the series.
151 Italics are also used to denote the name of a service input or output parameter or the name of a
152 structure or element of a structure that are usually defined in tables.
153 The italicized terms and names are also often written in camel-case (the practice of writing compound
154 words or phrases in which the elements are joined without spaces, with each element's initial letter
155 capitalized within the compound). For example, the defined term is AddressSpace instead of Address
156 Space. This makes it easier to understand that there is a single definition for AddressSpace, not
157 separate definitions for Address and Space.
158 A list of all parts of the IEC 62541 series is included in IEC 62541-1 clause 4 Structure of the OPC UA
159 series and published under the general title OPC Unified Architecture, can be found on the IEC
160 website.
161 The committee has decided that the contents of this publication will remain unchanged until the stability
162 date indicated on the IEC web site under "http://webstore.iec.ch" in the data related to the specific
163 publication. At this date, the publication will be
164 • reconfirmed,
165 • withdrawn,
166 • replaced by a revised edition, or
167 • amended.
169 A bilingual version of this publication may be issued at a later date.
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.
1 IEC CDV 62541-23 © IEC 2023
172 OPC Unified Architecture Specification
174 Part 23: Common ReferenceTypes
178 1 Scope
179 This part of the OPC Unified Architecture defines an Information Model. The Information Model defines
180 common ReferenceTypes.
181 2 Normative references
182 The following referenced documents are indispensable for the application of this OPC UA part. For
183 dated references, only the edition cited applies. For undated references, the latest edition of the
184 referenced document (including any amendments and errata) applies.
185 IEC 62541-1, OPC Unified Architecture – Part 1: Overview and Concepts
186 IEC 62541-3, OPC Unified Architecture – Part 3: Address Space Model
187 IEC 62541-5, OPC Unified Architecture – Part 5: Information Model
189 3 Terms, definitions, abbreviated terms, and conventions
190 Terms and definitions
191 For the purposes of this document, the terms and definitions given in IEC 62541-1, IEC 62541-3, and
192 IEC 62541-5 apply.
193 All used terms are italicized in this document.
194 Abbreviated terms
195 CPU Central Processing Unit
196 IO Input/Output
197 IP Internet Protocol
198 PC Personal Computer
199 PCI Peripheral Component Interconnect
200 PHY Physical Layer
201 PLC Programmable Logic Controller
202 RFID Radio Frequency Identification

2 IEC CDV 62541-23 © IEC 2023
203 4 OPC UA ReferenceTypes
204 Overview
205 The following Figure 1 gives an overview of the ReferenceTypes defined in the following subsections.
References
HierarchicalReferences NonHierarchicalReferences
IsExecutableOn IsPhysicallyConnectedTo Utilizes
HasChild Controls
(asymmetric) (symmetric) (asymmetric)
RepresentsSameEntityAs
Aggregates
(symmetric)
Requires
IsExecutingOn
IsHostedBy
(asymmetric) (asymmetric)
HasComponent
RepresentsSameHardwareAs RepresentsSameFunctionalityAs
(symmetric) (symmetric)
HasPhysicalComponent
HasContainedComponent HasAttachedComponent
207 Figure 1 – Overview of ReferenceTypes
208 IsExecutableOn
209 Overview
210 This ReferenceType can be used to expose the relation between a software component and its
211 execution environment. For example, it can be used to expose which firmware (including its version)
212 is available on a field device.
213 Definition
214 The IsExecutableOn is a concrete ReferenceType and can be used directly. It is a subtype of
215 NonHierarchicalReferences.
216 The semantic of this ReferenceType is to relate a software component to its execution environment
217 that the software needs to run (e.g. Hardware component, Task or Thread). The relationship shows
218 that the execution environment the reference points to, is able to execute the software component.
219 This does not imply that the software component is currently being executed or running. To show that
220 the software is running in an environment, IsExecutingOn should be used.
221 The SourceNode of References of this ReferenceType shall be an Object or ObjectType representing
222 a software component.
223 The TargetNode of References of this ReferenceType shall be an Object or ObjectType representing
224 an execution environment for a software component, which might be a piece of hardware (e.g. Device)
225 or some other environment like a task, thread or software execution framework.
226 IsExecutableOn is formally defined in Table 1.

3 IEC CDV 62541-23 © IEC 2023
227 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
229 IsExecutingOn
230 Overview
231 This ReferenceType can be used to expose the relation between a software component and its
232 execution environment it is currently executing on. References of this ReferenceType might be very
233 dynamic and need to disappear as soon, as the software component is not being executed anymore.
234 For example, it can be used to expose that a PLC program is currently running on a specific task of a
235 PLC.
236 Definition
237 The IsExecutingOn is a concrete ReferenceType and can be used directly. It is a subtype of Utilizes.
238 The semantic of this ReferenceType is to relate a software component to its execution environment it
239 is currently executing on (e.g. Hardware component, Task or Thread). References of this
240 ReferenceType shall only be used when the software component is currently executed / running.
241 The SourceNode of References of this ReferenceType shall be an Object or ObjectType representing
242 a software component.
243 The TargetNode of References of this ReferenceType shall be an Object or ObjectType representing
244 an execution environment for a software component, which might be a piece of hardware (e.g. Device)
245 or some other environment like a task, thread or software execution framework.
246 IsExecutingOn is formally defined in Table 2.
247 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
250 Controls
251 Overview
252 This ReferenceType can be used to expose the relation between an object controlling other objects
253 and the controlled objects. For example, it can be used to relate a PLC to the field devices or machine-
254 modules controlled by the PLC or a software component to the hardware components controlled by
255 the software component.
256 Definition
257 The Controls is a concrete ReferenceType and can be used directly. It is a subtype of
258 HierarchicalReferences.
4 IEC CDV 62541-23 © IEC 2023
259 The semantic of this ReferenceType is to relate the controlling component to the components
260 controlled by the controlling component.
261 The SourceNode of References of this ReferenceType shall be an Object or ObjectType representing
262 the controlling component, as for example a PLC or a software component.
263 The TargetNode of References of this ReferenceType shall be an Object representing a component
264 that is controlled by the TargetNode.
265 Controls is formally defined in Table 3.
266 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
268 Utilizes
269 Overview
270 This ReferenceType can be used to expose the relation between a component to other components,
271 that the component needs in order to work. In contrast to the Requires ReferenceType, this non-
272 hierarchical ReferenceType allows loops, e.g. both components need each other in order to work. In
273 that case, there would be two References, the first one pointing from one component to the other, and
274 the second one vice versa. For example, a fan in a PC needs the power supply in order to work and
275 the power supply needs the cooling from the fan, that it is not overheating. An example of a non-
276 looping usage is that a robot utilizes a vision system in order to get the position where to grab
277 something.
278 Definition
279 The Utilizes is a concrete ReferenceType and can be used directly. It is a subtype of
280 NonHierarchicalReferences.
281 The semantic of this ReferenceType is to relate a component to other components that are needed by
282 the component in order to work.
283 The SourceNode of References of this ReferenceType shall be an Object or ObjectType representing
284 a component that utilizes the TargetNode in order to work.
285 The TargetNode of References of this ReferenceType shall be an Object or ObjectType representing
286 the required component.
287 Requires is formally defined in Table 4.
288 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
5 IEC CDV 62541-23 © IEC 2023
290 Requires
291 Overview
292 This ReferenceType can be used to expose the relation between a component to other components,
293 that the component requires in order to work. In contrast to the HasComponent ReferenceType, the
294 related components are not considered to be subcomponents of the component. In contrast to the
295 Utilizes ReferenceType, this hierarchical ReferenceType exposes a non-looping hierarchy of
296 dependencies.
297 For example, it can be used to relate an axis of a motion device to its required powertrains or a
298 software component to other software components required to execute the software component, like
299 for example libraries.
300 Definition
301 The Requires is a concrete ReferenceType and can be used directly. It is a subtype of
302 HierarchicalReferences.
303 The semantic of this ReferenceType is to relate a component to other components it requires in order
304 to work.
305 The SourceNode of References of this ReferenceType shall be an Object or ObjectType representing
306 a component that requires the TargetNode in order to work.
307 The TargetNode of References of this ReferenceType shall be an Object representing the required
308 component used by the SourceNode.
309 Requires References shall not lead to loops, that is, starting from Node “A” and only following
310 References of ReferenceType Requires or subtypes it shall never be possible to return to “A”. But it is
311 allowed that following the References there may be more than one path leading to another Node “B”.
312 Requires is formally defined in Table 5.
313 Table 5 – Requires Definition
Attributes Value
BrowseName Req
...