The server specific ObjectTypes like vendor specific Ctrl Configuration types or user specific Ctrl Function Block types can be found by a UA client by following the type hierarchy.
To provide UA clients all relevant server specific types in one place, the Ctrl Function Block types shall be referenced directly or indirectly from the CtrlTypes Folder Object using Organizes References. Other types like Ctrl Resources or Ctrl Program types may be included in addition. The CtrlTypes node is formally defined in Table 36
Table 36 – CtrlTypes definition
|Organized by the ObjectType Folder defined in OPC 10000-5|
|Organizes||Object||<Server specific>||FolderType||Optional server specific additional structuring of the type information building to a type catalogue|
|Organizes||ObjectType||<Server specific>||Server specific Object Types|
The server may provide additional Folder objects below the CtrlTypes Object to organize the types. This can be used to create a library structure like in the example in Figure 26.
Figure 26 – CtrlTypes Folder used to structure POU types