The three attributes opRcvd, opOk, and tOpOk are used to indicate:
1. An event (opRcvd) when a operate command is received (no timestamp given)
2. An event (opOk) when the command has been accepted and a timestamp (tOpOk) when the output would be activated.
Reporting of These signals requires some additional rules, because:
a. If the DataSet member is xxx$OR then with opRcvd=set to True, all three attributes will be reported. opOk=False, what is the timestamp value?? opOk is not yet true!
b. If the DataSet members are xxx$OR.opRcvd ... would work when opRcvd=set to True; but how to report opOk and tOpOk? in a xxx$OR ! Works ... but what is now the value of opRcd?
Proposal
1. The indications must be defined as transient signals. Add a text similar to 7-4: The attributes opRcvd and opOk are transient. The state change from TRUE to FALSE shall not issue an event, e.g. to generate a report and log.
2. In case the three attributes are defined in a FCD (xxx$OR) then the timestamp tOpOk shall be ignored when opRcvd is True.
Discussion
Created
Status
no change required
25 Sep 13
Not Applicable
tOpOk as defined in 7-3 specifies the opOk - operate ok - time.
tOpOk is set by the application. At the time opRcvd changes, then the tOpOk attribute does not change till the application set the opOk attribute.
The first report will indicate that an operate request has been received, while the second report will indicate that the operate request has been performed/would have been performed depending on the Beh of the logical node.
1) See IEC 61850-7-2 controllable state machines - the transient properties are reflechted in the states.
2) tOpOk definition specify its semantic. No need to overspecify it when being reported. 7-3 defines as well the dependancies of the "t" attribute and never overspecified it in describing how a FCD with a stSeld change will be reported, and that the attribute "t" shall be ignored.