The OPC UA client shows the topology in a hierarchical tree to the user. The tree is provided by an OPC UA server for FDT OPC Information Model.

If the OPC UA server supports a network topology, it is provided according to the 'Device Integration Host Model' defined in OPC UA DI.

Network/communication topology

Physical topology

OPC Client has the UI windows for displaying the device details information.

If the device has the blocks, the UI window displays block names which the device has.

If a device has blocks, the UI window displays parameter names which are included in blocks.

If a device does not have a block, the UI window displays parameter names which the device has.

OPC Client displays a name list to user.

If selected device has blocks (if the device is FF-H1 or PROFIBUS PA), OPC Client displays the block name list.

If the object type of selected item is “Parameter”, OPC Server retrieves available attributes of the selected parameter.

For the enumeration case, an OPC Client displays the corresponding label with the value.

[Hierarchy of items]

[Up to the parameter]

FF-H1 / PROFIBUS PA : {Device} --- {Block} --- {Parameter}

HART : {Device} --- {Parameter}

[Up to the element]

FF-H1 : {Device} --- {Block} --- {Parameter} --- {Element(*)}

(*) Element = the member variable of the structure

[Up to the enumeration]

FF-H1 / PROFIBUS PA : {Device} --- {Block} --- {Parameter} --- {Enumeration}

FF-H1 : {Device} --- {Block} --- {Parameter} --- {Element} --- {Enumeration}

HART : {Device} --- {Parameter} --- {Enumeration}

OPC Client has the UI windows for displaying the device details information.

The UI window displays parameter names, its’ engineering units and values (if the parameter is readable).

When OPC Client displays the value of a parameter, the value is displayed according to the “display format“, which is described in the DD.

If the OPC Client also has the parameter-write-function and if the parameter is writable, an UI-element for writing the value to a parameter is displayed.

Topology and device node are available in OPC UA Server

Device is connected to the OPC UA Server.

OPC Client gets the parameter list of a device from OPC Server.

To display the parameter name and its value, OPC Client tries to get the detail information of each parameter.

On the OPC client, user can see the parameter names, and can see the detail information for each parameter.

Detail Information of parameter:

the data type, the label name, the minimum value, the maximum value, the engineering units, writable, readable, the enumeration list, the display format, the edit format.

To use the attributes of a device parameter which is gotten by this use case, OPC Client can work as follows.

[For read parameter]

OPC Client can recognize a parameter is readable or not, and then OPC Client gets the value of the parameter via OPC Server from the device.

OPC Client displays the corresponding label with the value if the data type of a parameter is the enumeration, otherwise (if the data type is not the enumeration) OPC Client displays the value according to the “display format“.

[For write parameter]

OPC Client can recognize a parameter is writable or not, and then OPC Client can check the entered value whether the data type, and the minimum value and the maximum value of the entered value are correct or not when user tries to write a value to a parameter.

DTM can provide the NE107 status as the device status by the next procedure.

Reading the data from the device parameters which express the device status or the results of the diagnosis of the device.

Calculating the bits and mapping to the NE107 status definition.

Device node is available in OPC UA Server

Device is connected to the OPC UA Server (means online or only somehow accessible?)

Use case B.2 (List Topology)