This ObjectTypedefines a generic model for elements in a device or component topology. Among others, it introduces FunctionalGroups, ParameterSet, and MethodSet. Figure 2shows the TopologyElementType. It is formally defined in Table 12.

Figure 2– Components of the TopologyElementType

Table 12– TopologyElementType definition

Attribute	Value
BrowseName	TopologyElementType
IsAbstract	True
References	NodeClass	BrowseName	DataType	TypeDefinition	Other
Subtype of the 0:BaseObjectTypedefined in OPC 10000-5
0:HasSubtype	ObjectType	ComponentType	Defined in 4.6
0:HasSubtype	ObjectType	BlockType	Defined in 4.11
0:HasSubtype	ObjectType	ConnectionPointType	Defined in 5.4
0:HasComponent	Object	<GroupIdentifier>		FunctionalGroupType	OP
0:HasComponent	Object	Identification		FunctionalGroupType	O
0:HasComponent	Object	Lock		LockingServicesType	O
0:HasComponent	Object	ParameterSet		0:BaseObjectType	O
0:HasComponent	Object	MethodSet		0:BaseObjectType	O
Conformance Units
DI Information Model

The TopologyElementTypeis abstract. There will be no instances of a TopologyElementTypeitself, but there will be instances of subtypes of this type. In this specification, the term TopologyElementgenerically refers to an instance of any ObjectTypederived from the TopologyElementType.

FunctionalGroupsare an essential aspect introduced by the TopologyElementType. FunctionalGroupsare used to structure Nodeslike Properties, Parametersand Methodsaccording to their application such as configuration, diagnostics, asset management, condition monitoring and others.

FunctionalGroupsare specified in 4.4.

A FunctionalGroupcalled Identificationcan be used to organize identification information of this TopologyElement(see 4.4.2). Identification information typically includes the Propertiesdefined by the VendorNameplateor TagNameplate Interfacesand additional application specific information.

TopologyElementsmay also support LockingServices(defined in 7).

Clientsshall use the LockingServicesif they need to make a set of changes (for example, several Writeoperations and Methodinvocations) and where a consistent state is available only after all of these changes have been performed. The main purpose of locking a TopologyElementis avoiding concurrent modifications.

The lock applies to the complete TopologyElement(including all components such as blocks or modules).Serversmay expose a Lock Object on a component TopologyElementto allow independent locking of components, if no lock is applied to the top-level TopologyElement.

If the Online/Offline model is supported (see 6.3), the lock always applies to both the online and the offline version.

ParameterSetand MethodSetare defined as standard containers for systems that have a flat list of Parameters or Methods with unique names. In such cases, the Parametersare components of the “ParameterSet” as a flat list of Parameters. The Methodsare kept the same way in the “MethodSet”.

The MethodSetis only available if it includes at least one Method.

The components of the TopologyElementTypehave additional references as defined in Table 13.

Table 13– TopologyElementType Additional Subcomponents

Source Path	References	NodeClass	BrowseName	DataType	TypeDefinition	Other
ParameterSet	0:HasComponent	Variable	<ParameterIdentifier>	0:BaseDataType	0:BaseDataVariableType	MP