CRGt200 ms1tSecurityt150 ms>1CRCRLLCGAND ORtANDen05000746.vsdIEC05000746 V1 EN-USFigure 197: Guard signal logic with unblocking scheme and with settingUnblock = RestartORt1CRCRGCRLtSecurityIEC11000253-1-en.vsdIEC11000253 V1 EN-USFigure 198: Guard signal logic with unblocking scheme and with settingUnblock = NoRestartThe unblocking function can be set in three operation modes (setting Unblock):Off The unblocking function is out of operationNo restart Communication failure shorter thantSecurity will be ignoredIf CRG disappears a CRL signal will be transferred to the trip logicThere will not be any information in case of communication failure (LCG)Restart Communication failure shorter thantSecurity will be ignoredIt sends a defined (150 ms) CRL after the disappearance of the CRG signalThe function will activate LCG output in case of communication failureIf the communication failure comes and goes (<200 ms) there will not be recurrentsignalling13.1.6.6 Intertrip scheme M13893-36 v5In the direct intertrip scheme, the send signal CS is sent from an underreachingzone that is tripping the line.The received signal CR is directly transferred to a trip for tripping without localcriteria. The signal is further processed in the tripping logic.1MRK 505 394-UEN A Section 13Scheme communicationLine differential protection RED650 2.2 IEC 407Technical manual
