This is a subtype of AuditHistoryUpdateEventType and is used the insertion or change of an annotation. This type follows all the behaviour of its parent type. Its representation in the AddressSpace is formally defined in Table 18.

Table 18 – AuditHistoryAnnotationUpdateEventType definition

Attribute	Value
BrowseName	AuditHistoryAnnotationUpdateEventType
IsAbstract	False
References	NodeClass	BrowseName	DataType	TypeDefinition	ModellingRule
Subtype of the AuditHistoryUpdateEventType defined in OPC 10000-3, i.e. it has HasProperty References to the same Nodes.
HasProperty	Variable	PerformInsertReplace	PerformUpdateType	PropertyType	Mandatory
HasProperty	Variable	NewValues	Annotation[]	PropertyType	Mandatory
HasProperty	Variable	OldValues	Annotation[]	PropertyType	Mandatory
ConformanceUnits
Historical Access Annotation Audit Events

This EventType inherits all Properties of the AuditHistoryUpdateEventType. Their semantic is defined in OPC 10000-3.

The PerformInsertReplace enumeration reflects the corresponding parameter on the Service call.

The NewValues identify the Annotation that was written. In the case of a remove, it is expected to be a null value.

The OldValues identify the value that the Annotation contained before the write. It is acceptable for a Server that does not have this information to report a null value in the case of an update. In the case of an insert it is expected to be a null value.

Both the NewValues and the OldValues will contain a value in the DataType and encoding used for writing the value.