permissive tripping at the local end. This blocking condition is maintained longenough to ensure that no unwanted operation will occur as a result of the currentreversal.On verification of a weak end infeed condition, the weak end infeed logic providesan output for sending the received teleprotection signal back to the remote sendingend and other output(s) for local tripping. For terminals equipped for single- andtwo-pole tripping, outputs for the faulted phase(s) are provided. Undervoltagedetectors are used to detect the faulted phase(s).12.2.3 Function block SEMOD53507-9 v6IEC06000287-2-en.vsdZCRWPSCHU3P*BLOCKIRVBLKIRVWEIBLK1WEIBLK2VTSZCBOPENCRLIRVLTRWEITRWEIL1TRWEIL2TRWEIL3ECHOIEC06000287 V2 EN-USFigure 224: ZCRWPSCH function block12.2.4 SignalsPID-3521-INPUTSIGNALS v8Table 255:ZCRWPSCH Input signalsName Type Default DescriptionU3P GROUPSIGNAL- Group signal for voltage inputBLOCK BOOLEAN 0 Block of functionIRVBLK BOOLEAN 0 Block of current reversal functionIRV BOOLEAN 0 Activation of current reversal logicWEIBLK1 BOOLEAN 0 Block of WEI logicWEIBLK2 BOOLEAN 0 Block of WEI logic due to operation of otherprotectionsVTSZ BOOLEAN 0 Block of trip from WEI logic through fuse-failurefunctionCBOPEN BOOLEAN 0 Block of trip from WEI logic by an open breakerCRL BOOLEAN 0 POR Carrier receive for WEI logicSection 12 1MRK 506 382-UEN AScheme communication442 Line distance protection REL650 2.2 IECTechnical manual
