To prevent damages on the generator or turbine, it is essential that high speed trippingis provided in case of inadvertent energization of the generator. This tripping shouldbe almost instantaneous (< 100 ms).There is a risk that the current into the generator at inadvertent energization will belimited so that the “normal” overcurrent or underimpedance protection will not detectthe dangerous situation. The delay of these protection functions might be too long. Forbig and important machines, fast protection against inadvertent energizing should,therefore, be included in the protective scheme.11.1.3 Function blockIEC05000372-2-en.vsdCVGAPCI3P*U3P*BLOCKBLKOC1BLKOC1TRENMLTOC1BLKOC2BLKOC2TRENMLTOC2BLKUC1BLKUC1TRBLKUC2BLKUC2TRBLKOV1BLKOV1TRBLKOV2BLKOV2TRBLKUV1BLKUV1TRBLKUV2BLKUV2TRTRIPTROC1TROC2TRUC1TRUC2TROV1TROV2TRUV1TRUV2STARTSTOC1STOC2STUC1STUC2STOV1STOV2STUV1STUV2BLK2NDDIROC1DIROC2UDIRLOWCURRENTICOSFIVOLTAGEUIANGLEIEC05000372 V2 ENFigure 271: CVGAPC function block11.1.4 SignalsTable 326:CVGAPC Input signalsName Type Default DescriptionI3P GROUPSIGNAL- Group signal for current inputU3P GROUPSIGNAL- Group signal for voltage inputBLOCK BOOLEAN 0 Block of functionBLKOC1 BOOLEAN 0 Block of over current function OC1BLKOC1TR BOOLEAN 0 Block of trip for over current function OC1ENMLTOC1 BOOLEAN 0 When activated, the current multiplier is in use forOC1Table continues on next pageSection 11 1MRK502052-UEN BMultipurpose protection566Technical manual
