IEC 62541-3:2015

IEC 62541-3 ®
Edition 2.0 2015-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
OPC unified architecture –
Part 3: Address Space Model
Architecture unifiée OPC –
Partie 3: Modèle de l'Espace d'Adressage

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IEC 62541-3 ®
Edition 2.0 2015-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
OPC unified architecture –
Part 3: Address Space Model
Architecture unifiee OPC –
Partie 3: Modèle de l'Espace d'Adressage

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 25.040.40; 35.100 ISBN 978-2-8322-2385-7

– 2 – IEC 62541-3:2015 © IEC 2015
CONTENTS
FOREWORD . 10
1 Scope . 12
2 Normative references . 12
3 Terms, definitions, abbreviations and conventions . 13
3.1 Terms and definitions . 13
3.2 Abbreviations . 14
3.3 Conventions . 14
3.3.1 Conventions for AddressSpace figures. 14
3.3.2 Conventions for defining NodeClasses . 14
4 AddressSpace concepts . 16
4.1 Overview. 16
4.2 Object Model . 16
4.3 Node Model . 16
4.3.1 General. 16
4.3.2 NodeClasses . 17
4.3.3 Attributes . 17
4.3.4 References . 17
4.4 Variables . 18
4.4.1 General. 18
4.4.2 Properties . 18
4.4.3 DataVariables . 18
4.5 TypeDefinitionNodes . 19
4.5.1 General. 19
4.5.2 Complex TypeDefinitionNodes and their InstanceDeclarations . 20
4.5.3 Subtyping . 20
4.5.4 Instantiation of complex TypeDefinitionNodes . 21
4.6 Event Model . 22
4.6.1 General. 22
4.6.2 EventTypes . 22
4.6.3 Event Categorization. 23
4.7 Methods . 23
5 Standard NodeClasses . 23
5.1 Overview. 23
5.2 Base NodeClass . 24
5.2.1 General. 24
5.2.2 NodeId . 24
5.2.3 NodeClass . 24
5.2.4 BrowseName . 24
5.2.5 DisplayName . 25
5.2.6 Description . 25
5.2.7 WriteMask. 25
5.2.8 UserWriteMask . 26
5.3 ReferenceType NodeClass . 26
5.3.1 General. 26
5.3.2 Attributes . 27
5.3.3 References . 28

5.4 View NodeClass . 29
5.5 Objects . 31
5.5.1 Object NodeClass . 31
5.5.2 ObjectType NodeClass . 33
5.5.3 Standard ObjectType FolderType . 35
5.5.4 Client-side creation of Objects of an ObjectType . 35
5.6 Variables . 35
5.6.1 General. 35
5.6.2 Variable NodeClass . 35
5.6.3 Properties . 39
5.6.4 DataVariable . 39
5.6.5 VariableType NodeClass . 40
5.6.6 Client-side creation of Variables of an VariableType . 42
5.7 Method NodeClass . 42
5.8 DataTypes . 44
5.8.1 DataType Model. 44
5.8.2 Encoding Rules for different kinds of DataTypes . 46
5.8.3 DataType NodeClass . 47
5.8.4 DataTypeDictionary, DataTypeDescription, DataTypeEncoding and
DataTypeSystem . 48
5.9 Summary of Attributes of the NodeClasses . 50
6 Type Model for ObjectTypes and VariableTypes . 51
6.1 Overview. 51
6.2 Definitions. 51
6.2.1 InstanceDeclaration . 51
6.2.2 Instances without ModellingRules . 51
6.2.3 InstanceDeclarationHierarchy . 52
6.2.4 Similar Node of InstanceDeclaration . 52
6.2.5 BrowsePath . 52
6.2.6 Attribute Handling of InstanceDeclarations . 52
6.2.7 Attribute Handling of Variable and VariableTypes . 52
6.2.8 NodeIds of InstanceDeclarations. 52
6.3 Subtyping of ObjectTypes and VariableTypes . 53
6.3.1 Overview . 53
6.3.2 Attributes . 53
6.3.3 InstanceDeclarations . 53
6.4 Instances of ObjectTypes and VariableTypes . 56
6.4.1 Overview . 56
6.4.2 Creating an Instance . 57
6.4.3 Constraints on an Instance . 57
6.4.4 ModellingRules . 58
6.5 Changing Type Definitions that are already used . 66
7 Standard ReferenceTypes . 66
7.1 General . 66
7.2 References ReferenceType . 67
7.3 HierarchicalReferences ReferenceType . 67
7.4 NonHierarchicalReferences ReferenceType . 68
7.5 HasChild ReferenceType . 68
7.6 Aggregates ReferenceType . 68

– 4 – IEC 62541-3:2015 © IEC 2015
7.7 HasComponent ReferenceType. 68
7.8 HasProperty ReferenceType . 69
7.9 HasOrderedComponent ReferenceType . 69
7.10 HasSubtype ReferenceType . 69
7.11 Organizes ReferenceType. 69
7.12 HasModellingRule ReferenceType . 70
7.13 HasTypeDefinition ReferenceType . 70
7.14 HasEncoding ReferenceType . 70
7.15 HasDescription ReferenceType . 70
7.16 GeneratesEvent . 71
7.17 AlwaysGeneratesEvent . 71
7.18 HasEventSource . 71
7.19 HasNotifier . 71
8 Standard DataTypes . 73
8.1 General . 73
8.2 NodeId . 73
8.2.1 General. 73
8.2.2 NamespaceIndex . 73
8.2.3 IdentifierType . 74
8.2.4 Identifier value . 74
8.3 QualifiedName . 75
8.4 LocaleId . 75
8.5 LocalizedText . 76
8.6 Argument . 76
8.7 BaseDataType . 76
8.8 Boolean . 76
8.9 Byte . 76
8.10 ByteString . 77
8.11 DateTime . 77
8.12 Double . 77
8.13 Duration . 77
8.14 Enumeration . 77
8.15 Float . 77
8.16 Guid . 77
8.17 SByte . 77
8.18 IdType . 77
8.19 Image . 77
8.20 ImageBMP . 78
8.21 ImageGIF . 78
8.22 ImageJPG . 78
8.23 ImagePNG . 78
8.24 Integer . 78
8.25 Int16 . 78
8.26 Int32 . 78
8.27 Int64 . 78
8.28 TimeZoneDataType. 78
8.29 NamingRuleType . 78
8.30 NodeClass . 79
8.31 Number . 79

8.32 String . 79
8.33 Structure . 79
8.34 UInteger . 79
8.35 UInt16 . 79
8.36 UInt32 . 79
8.37 UInt64 . 79
8.38 UtcTime . 80
8.39 XmlElement . 80
8.40 EnumValueType . 80
9 Standard EventTypes . 80
9.1 General . 80
9.2 BaseEventType . 81
9.3 SystemEventType . 81
9.4 ProgressEventType . 81
9.5 AuditEventType . 82
9.6 AuditSecurityEventType . 83
9.7 AuditChannelEventType . 83
9.8 AuditOpenSecureChannelEventType . 83
9.9 AuditSessionEventType . 83
9.10 AuditCreateSessionEventType . 84
9.11 AuditUrlMismatchEventType . 84
9.12 AuditActivateSessionEventType . 84
9.13 AuditCancelEventType . 84
9.14 AuditCertificateEventType . 84
9.15 AuditCertificateDataMismatchEventType . 84
9.16 AuditCertificateExpiredEventType . 84
9.17 AuditCertificateInvalidEventType . 84
9.18 AuditCertificateUntrustedEventType . 84
9.19 AuditCertificateRevokedEventType . 84
9.20 AuditCertificateMismatchEventType . 85
9.21 AuditNodeManagementEventType . 85
9.22 AuditAddNodesEventType . 85
9.23 AuditDeleteNodesEventType . 85
9.24 AuditAddReferencesEventType . 85
9.25 AuditDeleteReferencesEventType . 85
9.26 AuditUpdateEventType . 85
9.27 AuditWriteUpdateEventType . 85
9.28 AuditHistoryUpdateEventType . 85
9.29 AuditUpdateMethodEventType . 85
9.30 DeviceFailureEventType . 85
9.31 SystemStatusChangeEventType . 86
9.32 ModelChangeEvents . 86
9.32.1 General. 86
9.32.2 NodeVersion Property . 86
9.32.3 Views . 86
9.32.4 Event Compression . 86
9.32.5 BaseModelChangeEventType . 86
9.32.6 GeneralModelChangeEventType . 87
9.32.7 Guidelines for ModelChangeEvents . 87

– 6 – IEC 62541-3:2015 © IEC 2015
9.33 SemanticChangeEventType . 87
9.33.1 General. 87
9.33.2 ViewVersion and NodeVersion Properties . 87
9.33.3 Views . 88
9.33.4 Event Compression . 88
Annex A (informative) How to use the Address Space Model . 89
A.1 Overview. 89
A.2 Type definitions . 89
A.3 ObjectTypes. 89
A.4 VariableTypes . 90
A.4.1 General. 90
A.4.2 Properties or DataVariables . 90
A.4.3 Many Variables and / or structured DataTypes . 90
A.5 Views . 91
A.6 Methods . 91
A.7 Defining ReferenceTypes . 91
A.8 Defining ModellingRules . 91
Annex B (informative) OPC UA Meta Model in UML . 92
B.1 Background. 92
B.2 Notation . 92
B.3 Meta Model . 94
B.3.1 Base . 94
B.3.2 ReferenceType . 94
B.3.3 Predefined ReferenceTypes . 96
B.3.4 Attributes . 96
B.3.5 Object and ObjectType . 97
B.3.6 EventNotifier . 98
B.3.7 Variable and VariableType . 98
B.3.8 Method . 99
B.3.9 DataType . 100
B.3.10 View . 101
Annex C (normative) OPC Binary Type Description System . 102
C.1 Concepts . 102
C.2 Schema Description . 103
C.2.1 TypeDictionary . 103
C.2.2 TypeDescription . 103
C.2.3 OpaqueType . 104
C.2.4 EnumeratedType . 104
C.2.5 StructuredType . 105
C.2.6 FieldType . 105
C.2.7 EnumeratedValue . 107
C.2.8 ByteOrder . 107
C.2.9 ImportDirective . 107
C.3 Standard Type Descriptions . 107
C.4 Type Description Examples . 108
C.5 OPC Binary XML Schema . 110
C.6 OPC Binary Standard TypeDictionary . 111
Annex D (normative) Graphical Notation . 114

D.1 General . 114
D.2 Notation . 114
D.2.1 Overview . 114
D.2.2 Simple Notation . 114
D.2.3 Extended Notation . 116

Figure 1 – AddressSpace Node diagrams . 14
Figure 2 – OPC UA Object Model . 16
Figure 3 – AddressSpace Node Model . 17
Figure 4 – Reference Model . 18
Figure 5 – Example of a Variable defined by a VariableType . 19
Figure 6 – Example of a Complex TypeDefinition . 20
Figure 7 – Object and its Components defined by an ObjectType . 21
Figure 8 – Symmetric and Non-Symmetric References . 28
Figure 9 – Variables, VariableTypes and their DataTypes . 44
Figure 10 – DataType Model . 45
Figure 11 – Example of DataType Modelling . 50
Figure 12 – Subtyping TypeDefinitionNodes . 54
Figure 13 – The Fully-Inherited InstanceDeclarationHierarchy for BetaType . 55
Figure 14 – An Instance and its TypeDefinitionNode . 57
Figure 15 – Example for several References between InstanceDeclarations . 58
Figure 16 – Example on changing instances based on InstanceDeclarations . 60
Figure 17 – Example on changing InstanceDeclarations based on an
InstanceDeclaration . 61
Figure 18 – Use of the Standard ModellingRule New . 62
Figure 19 – Example using the Standard ModellingRules Optional and Mandatory . 63
Figure 20 – Example on using ExposesItsArray . 64
Figure 21 – Complex example on using ExposesItsArray . 64
Figure 22 – Example on using OptionalPlaceholder . 65
Figure 23 – Example on using MandatoryPlaceholder . 66
Figure 24 – Standard ReferenceType Hierarchy . 67
Figure 25 – Event Reference Example . 72
Figure 26 – Complex Event Reference Example . 73
Figure 27 – Standard EventType Hhierarchy . 81
Figure 28 – Audit Behaviour of a Server. 82
Figure 29 – Audit Behaviour of an Aggregating Server . 83
Figure B.1 – Background of OPC UA Meta Model . 92
Figure B.2 – Notation (I) . 93
Figure B.3 – Notation (II) . 93
Figure B.4 – Base . 94
Figure B.5 – Reference and ReferenceType. 95
Figure B.6 – Predefined ReferenceTypes . 96
Figure B.7 – Attributes . 97
Figure B.8 – Object and ObjectType . 98

– 8 – IEC 62541-3:2015 © IEC 2015
Figure B.9 – EventNotifier . 98
Figure B.10 – Variable and VariableType . 99
Figure B.11 – Method . 100
Figure B.12 – DataType . 100
Figure B.13 – View . 101
Figure C.1 – OPC Binary Dictionary Structure . 102
Figure D.1 – Example of a Reference connecting two Nodes . 115
Figure D.2 – Example of using a TypeDefinition inside a Node . 117
Figure D.3 – Example of exposing Attributes . 117
Figure D.4 – Example of exposing Properties inline . 118

Table 1 – NodeClass Table Conventions. 15
Table 2 – Base NodeClass . 24
Table 3 – Bit mask for WriteMask and UserWriteMask . 26
Table 4 – ReferenceType NodeClass . 27
Table 5 – View NodeClass . 30
Table 6 – Object NodeClass . 32
Table 7 – ObjectType NodeClass . 34
Table 8 – Variable NodeClass . 36
Table 9 – VariableType NodeClass . 41
Table 10 – Method NodeClass . 43
Table 11 – DataType NodeClass . 47
Table 12 – Overview of Attributes . 51
Table 13 – The InstanceDeclarationHierarchy for BetaType . 54
Table 14 – The Fully-Inherited InstanceDeclarationHierarchy for BetaType . 55
Table 15 – Rule for ModellingRules Properties when Subtyping . 59
Table 16 – Properties of ModellingRules . 61
Table 17 – NodeId Definition . 73
Table 18 – IdentifierType Values . 74
Table 19 – NodeId Null Values . 75
Table 20 – QualifiedName Definition . 75
Table 21 – LocaleId Examples .
...