NOTE: Other parts of this series of standards can extend the OPC UA Meta Model by adding Attributes and defining new ReferenceTypes.

Base is shown in Figure B.4.

Figure B.4 – Base

ReferenceType is shown in Figure B.5 and predefined ReferenceTypes in Figure B.6.

Figure B.5 – Reference and ReferenceType

If Symmetric is “false” an InverseName shall be provided.

Figure B.6 – Predefined ReferenceTypes

Attributes are shown in Figure B.7.

Figure B.7 – Attributes

There may be more Attributes defined in other parts of this series of standards.

Attributes used for references, which have a NodeId as DataType, are not shown in this diagram but are shown as stereotyped associations in the other diagrams.

Objects and ObjectTypes are shown in Figure B.8.

Figure B.8 – Object and ObjectType

EventNotifier are shown in Figure B.9.

Figure B.9 – EventNotifier

Variable and VariableType are shown in Figure B.10.

Figure B.10 – Variable and VariableType

The DataType of a Variable shall be the same as or a subtype of the DataType of its VariableType (referred with HasTypeDefinition).

If a HasProperty points to a Variable from a Base “A” then the following constraints apply:

• The Variable shall not be the SourceNode of a HasProperty or any other HierarchicalReferences Reference.
• All Variables having “A” as the SourceNode of a HasProperty Reference shall have a unique BrowseName in the context of “A”.

Method is shown in Figure B.11

Figure B.11 – Method

DataType is shown in Figure B.12.

Figure B.12 – DataType

View is shown in Figure B.13.

Figure B.13 – View