ABB IEC 61850 Edition 2 Communication Protocol Manual

Also see for IEC 61850 Edition 2: Communication protocol manual

the GI is started. A running GI shall be stopped and a new GI shall bestarted, when a new GI request is received while a GI is running.• Purge buffer (valid only for BRCB)• This BRCB attribute can be used by a client to clean the event bufferfrom old events. The events are discarded on request of the client. Thisfeature can be used to delete old events not transmitted to the client dueto stopped communication. After the link is reestablished the client candecide to clean the buffer or to receive the history.Trigger OptionsIEC 61850 has defined in total five different TrgOp. Three of them belonging todata attributes and marked per data attribute in the column TrgOp of the CDCtables in part 7–3. The other two belonging to the configuration of control blocks.• dchg = data-change• Whenever a process value has changed its value either binary or ameasurement a transmission is done.• qchg = quality change• Looking to the possibilities of the quality data attribute type (q) anychanges in the quality description will be transmitted.• dupd = data value update• This trigger option give the possibility to define that a transmissionshould be done on a condition which can be controlled by theapplication.• integrity• This trigger forces the transmission of all process values defined in thedata set when a timer value (the integrity period) expires.• general interrogation• This trigger is forced by the clients (= station level IED; NCC gateway,station HMI, ...). Normally a GI is asked for, when the client and theserver start or restart a session. When the client is able to receive theactual values and when the logical device has scanned all process valuesat least once, an image of the actual process signal status can betransmitted to the client.Note that the possible trigger options for each attributeare included and defined in the datatype template sectionin SCL.Section 6 1MRK 511 393-UEN AData sets and control blocks40 670 series 2.2 IECCommunication protocol manual