Section 7 Voltage protection7.1 Two step undervoltage protection UV2PTUV (27)7.1.1 IdentificationFunction description IEC 61850identificationIEC 60617identificationANSI/IEEE C37.2device numberTwo step undervoltage protection UV2PTUV3U<SYMBOL-R-2U-GREATER-THANV2 EN277.1.2 FunctionalityUndervoltages can occur in the power system during faults or abnormal conditions. Twostep undervoltage protection (UV2PTUV, 27) function can be used to open circuitbreakers to prepare for system restoration at power outages or as long-time delayed back-up to primary protection.UV2PTUV (27) has two voltage steps, where step 1 is settable as inverse or definite timedelayed. Step 2 is always definite time delayed.UV2PTUV (27) has a high reset ratio to allow settings close to system service voltage.7.1.3 Function blockANSI09000285-1-en.vsdUV2PTUV (27)V3P*BLOCKBLK1BLK2TRIPTRST1TRST2PICKUPPU_ST1PU_ST1_APU_ST1_BPU_ST1_CPU_ST2ANSI09000285 V1 ENFigure 68: UV2PTUV (27) function block1MRK 511 287-UUS A Section 7Voltage protection167Technical manual
