AddIns are used to attach OPC UA FX Information Model-specific content to an existing OPC UA Information Model. This is possible on the type definition level or the instance level. Only the type definition level is illustrated. The instance level would be identical, just applied to an instance instead of a type.
Extending the type definition with AddIns is done by adding the Reference HasAddIn to the FunctionalEntityType and FxAssetType. During instantiation, this leads to the creation of a new MyFunction instance and a new MyAsset instance, which are bound with these references to the OPC UA instance of the existing Information Model. This type of update is illustrated in Figure B.6Figure 4.
When to use:
- When it is important to include OPC UA FX functionality in an existing Information Model and the model does not include any of the functionality defined in UA FX [for example, any of the FxAssetType interfaces – IVendorNameplateType, ITagNameplateType]. An AddIn also allows the function to be placed as a separate object, which might be easier to profile as included or omitted.