D.2.1 Modelling of Asset relationships
The task of modelling an Asset is more than just describing a single simple Asset. It is modelling the relationships between the Assets. In OPC UA, relationships can be modelled as References, where a Reference provides semantic information about the relationship. OPC UA has defined a number of References in OPC 10000-23 that can be used for modelling Assets. This list is extended by this document. The following ReferenceTypes will be illustrated in various examples in this annex:
HasContainedComponent indicates that an Asset has another Asset contained in it.
HasBuiltInAsset indicates that an Asset has an integrated Asset, which is not removable.
HasPart indicates that an Asset has another Asset which can be removed.
HasAttachedComponent indicates that an Asset has physically/mechanically attached another Asset (this reference is a subtype of HasPhysicalComponent).
IsPhysicallyConnectedTo (symmetric) indicates that two Assets are physically connected to each other.
ConnectedTo (symmetric) indicates that two Assets are connected to each other by an electrical cable.
IsPartOfRedundantAssetSet indicates that an Asset is part of a group of Assets that form a redundant Asset.
Additional References can be defined or used to show additional relationships.