The HasGuard ReferenceTypeis a concrete ReferenceTypeand can be used directly. It is a subtype of HasComponent.

The semantic of this ReferenceTypeis to point from a Transitionto a Guard. The Guardindicates if the Transitioncan be used or not (see GuardVariableType). A Transitioncan only be used, if the Guardis "True". A Transitioncan point to several Guards. In that case, all Guardsneed to be "True" before the Transitioncan be used. If there is no Guard, the Transitioncan always be used (considered as if all Guardsare "True").

The SourceNodeof this ReferenceTypeshall be an Objectof the ObjectType TransitionTypeor one of its subtypes. The TargetNodeshall be a Variableof the VariableType GuardVariableTypeor one of its subtypes.

The representation of the HasGuard ReferenceTypein the AddressSpaceis specified in Table 19.

Table 19– HasGuard ReferenceType

Attribute	Value
BrowseName	HasGuard
InverseName	GuardOf
Symmetric	False
IsAbstract	False
References		NodeClass	BrowseName	DataType	TypeDefinition	ModellingRule
Subtype of the HasComponent ReferenceType defined in OPC 10000-5. Note that a Reference to this subtype is not shown in the definition of HasComponent.
Conformance Units
Base Info Choice States