This subtype of the OPC UA FolderType is used to structure Nodes like Properties, Parameters and Methods according to their application (e.g. maintenance, diagnostics, condition monitoring). Organizes References should be used when the elements are components in other parts of the TopologyElement that the FunctionalGroup belongs to. This includes Properties, Variables, and Methods of the TopologyElement or in Objects that are components of the TopologyElement either directly or via a subcomponent. The same Property, Parameter or Method might be useful in different application scenarios and therefore referenced from more than one FunctionalGroup.
FunctionalGroups can be nested.
FunctionalGroups can directly be instantiated. In this case, the BrowseName of a FunctionalGroup should indicate its purpose. A list of recommended BrowseNames is in 5.4.2.
Figure 6 shows the FunctionalGroupType components. It is formally defined in Table 11.
Figure 6 – FunctionalGroupType
Table 11 – FunctionalGroupType definition
|
Attribute |
Value |
||||
|
BrowseName |
FunctionalGroupType |
||||
|
IsAbstract |
False |
||||
|
References |
NodeClass |
BrowseName |
DataType |
TypeDefinition |
ModellingRule |
|
Subtype of the FolderType defined in OPC 10000-5 |
|||||
|
HasComponent |
Object |
<GroupIdentifier> |
|
FunctionalGroupType |
OptionalPlaceholder |
|
HasComponent |
Variable |
UIElement |
BaseDataType |
UIElementType |
Optional |
All BrowseNames for Nodes referenced by a FunctionalGroup with an Organizes Reference shall be unique.
The Organizes References may be present only at the instance, not the type. Depending on the current state of the TopologyElement the Server may decide to hide or unhide certain FunctionalGroups or (part of) their References. If a FunctionalGroup may be hidden on an instance the TypeDefinition shall use an appropriate ModellingRule like “Optional”.
If desirable, Nodes can be also children of FunctionalGroups. If such Nodes are defined, it is recommended to define a subtype of the FunctionalGroupType.
UIElement is the user interface element for this FunctionalGroup. See 5.4.3 for the definition of UIElements.
Examples in Annex B.1 illustrate the use of FunctionalGroups.
Table 12 includes a list of FunctionalGroups with name and purpose. If Servers expose a FunctionalGroup that corresponds to the described purpose, they should use the recommended BrowseName with the Namespace of this specification.
Table 12 – Recommended FunctionalGroup BrowseNames
|
BrowseName |
Purpose |
|
Configuration |
Parameters representing the configuration items of the TopologyElement. If the CurrentWrite bit is set in the AccessLevel Attribute they can be modified by Clients. |
|
Tuning |
Parameters and Methods to optimize the behavior of the TopologyElement. |
|
Maintenance |
Parameters and Methods useful for maintenance operations. |
|
Diagnostics |
Parameters and Methods for diagnostics. |
|
Statistics |
Parameters and Methods for statistics. |
|
Status |
Parameters which describe the general health of the TopologyElement. This can include diagnostic Parameters. |
|
Operational |
Parameters and Methods useful for during normal operation, like process data. |
|
Identification |
The Properties of the VendorNameplate Interface, like Manufacturer, SerialNumber or Properties of the TagNameplate will usually be sufficient as identification. If other Parameters or even Methods are required, all elements needed shall be organised in a FunctionalGroup called Identification. See Annex B.1 for an example. |
Servers can expose UIElements providing user interfaces in the context of their FunctionalGroup container. Clients can load such a user interface and display it on the Client side. The hierarchy of FunctionalGroups represents the tree of user interface elements.
The UIElementType is abstract and is mainly used as filter when browsing a FunctionalGroup. Only subtypes can be used for instances. No concrete UIElements are defined in this specification. FDI (Field Device Integration, see IEC 62769) specifies two concrete subtypes
- UIDs (UI Descriptions), descriptive user interface elements, and
- UIPs (UI Plug-Ins), programmed user interface elements.
The UIElementType is specified in Table 13.
Table 13 – UIElementType definition
|
Attribute |
Value |
||||
|
BrowseName |
UIElementType |
||||
|
IsAbstract |
True |
||||
|
DataType |
BaseDataType |
||||
|
References |
NodeClass |
BrowseName |
DataType |
TypeDefinition |
ModellingRule |
|
Subtype of the BaseDataVariableType defined in OPC 10000-5. |
|||||
The Value attribute of the UIElement contains the user interface element. Subtypes have to define the DataType (e.g. XmlElement or ByteString).