Directional operation can be combined together with corresponding communicationlogic in permissive or blocking teleprotection scheme. The same logic as fordirectional zero sequence current can be used. Current reversal and weak-end infeedfunctionality are available.8.5.3 Function blockNS4PTOCI3P*I3PDIR*U3P*BLOCKBLKTRBLKST1BLKST2BLKST3BLKST4ENMULT1ENMULT2ENMULT3ENMULT4TRIPTR1TR2TR3TR4STARTST1ST2ST3ST4STFWSTRVIEC10000054-2-en.vsdIEC10000054 V2 ENFigure 170: NS4PTOC function block8.5.4 SignalsTable 179:NS4PTOC Input signalsName Type Default DescriptionI3P GROUPSIGNAL- Group connection for operate currentI3PDIR GROUPSIGNAL- Group connection for directional currentU3P GROUPSIGNAL- Group connection for polarizing voltageBLOCK BOOLEAN 0 General blockBLKTR BOOLEAN 0 Block of tripBLKST1 BOOLEAN 0 Block of step 1 (Start and trip)BLKST2 BOOLEAN 0 Block of step 2 (Start and trip)BLKST3 BOOLEAN 0 Block of step 3 (Start and trip)BLKST4 BOOLEAN 0 Block of step 4 (Start and trip)ENMULT1 BOOLEAN 0 When activated, the current multiplier is in use forstep1ENMULT2 BOOLEAN 0 When activated, the current multiplier is in use forstep2ENMULT3 BOOLEAN 0 When activated, the current multiplier is in use forstep3ENMULT4 BOOLEAN 0 When activated, the current multiplier is in use forstep41MRK502052-UEN B Section 8Current protection375Technical manual
