Pickup1PU_ST1TRST1tReset1t1ANSI10000040-3-en.vsdANSI10000040 V3 EN-USFigure 93: Example for Definite Time Delay stage1 operation9.1.7.3 Blocking M15326-20 v8It is possible to block Two step undervoltage protection UV2PTUV (27) partially orcompletely, by binary input signals or by parameter settings, where:BLOCK: blocks all outputsBLKTR1: blocks all trip outputs of step 1BLK1: blocks all pickup and trip outputs related to step 1BLKTR2: blocks all trip outputs of step 2BLK2: blocks all pickup and trip outputs related to step 2If the measured voltage level decreases below the setting of IntBlkStVal1, either the tripoutput of step 1, or both the trip and the PICKUP outputs of step 1, are blocked. Thecharacteristic of the blocking is set by the IntBlkSel1 parameter. This internal blockingcan also be set to Disabled resulting in no voltage based blocking. Correspondingsettings and functionality are valid also for step 2.In case of disconnection of the high voltage component the measured voltage will getvery low. The event will PICKUP both the under voltage function and the blockingfunction, as seen in figure 94. The delay of the blocking function must be set less thanthe time delay of under voltage function.Section 9 1MRK 511 408-UUS AVoltage protection282 Phasor measurement unit RES670 2.2 ANSITechnical manual
