Introduction

3rd party SCADA needs to use OFS software services to implement the system time stamping solution.

Event Group

A particular OPC group named: ##TSEventsGroup## needs to be created to manage time stamped variables. This group is referenced as Events Group in this section.

Each OPC client can only create 1 OPC events group.

This Events Group complies with the following rules:

• If the Service support tab is not set to Available for the OFS alias of an item, that item is not added and an E_FAIL error detected message is returned.

• Items for which the Time-stamped Event Support custom property is set to 1 can be added to the Events Group.

  Items for which the Time-stamped Event Support custom property is set to 0 can also be added to the Events Group but a message is displayed in OFS diagnostics window (Example of message: Item ‘myvar’ has not time-stamped property set; it will be ignored).

• The same item can not be added more than once in the Events Group otherwise an OPC_E_DUPLICATE_NAME error detected message is returned.

• Items associated to a same OFS alias cannot be added in several client Events Group; otherwise an E_FAIL error detected message is returned.

• OFS specific items can not be added in the Events Group; otherwise an E_FAIL error detected message is returned.

• If one of the following operations is performed, an E_FAIL error detected message is returned immediately:

  • IOPCGroupStateMgt::SetName()

  • IOPCGroupStateMgt::CloneGroup()

  • Any IOPCSyncIO method

  • Any IOPCSyncIO2 method

For more details, refer to topic Time Stamped Events Configuration in OPC Factory Server User Manual.

Specific Items