ResetTypeCrvn: Set reset type curve for step n. This parameter can be set:Instantaneous,Frozen time,Linearly decreased. The default setting is Instantaneous.tIResetn: Reset time for step n if inverse time delay is used, given in s. The default valueis 25 ms.TDn: Time multiplier for inverse time characteristic. This parameter is used for co-ordination between different inverse time delayed undervoltage protections.ACrvn, BCrvn, CCrvn, DCrvn, PCrvn: Parameters for step n, to set to createprogrammable undervoltage inverse time characteristic. Description of this can be foundin the technical reference manual.CrvSatn: Set tuning parameter for step n. When the denominator in the expression of theprogrammable curve is equal to zero the time delay will be infinity. There will be anundesired discontinuity. Therefore, a tuning parameter CrvSatn is set to compensate forthis phenomenon. In the voltage interval Pickup> up to Pickup> · (1.0 + CrvSatn/100) theused voltage will be: Pickup> · (1.0 + CrvSatn/100). If the programmable curve is usedthis parameter must be calculated so that:0100CrvSatnB C× - >EQUATION1448 V1 EN (Equation 79)HystAbsn: Absolute hysteresis for step n, set in % of VBase. The setting of this parameteris highly dependent of the application.8.4 Voltage differential protection VDCPTOV (60)8.4.1 IdentificationFunction description IEC 61850identificationIEC 60617identificationANSI/IEEE C37.2device numberVoltage differential protection VDCPTOV - 608.4.2 ApplicationThe Voltage differential protection VDCPTOV (60) functions can be used in somedifferent applications.• Voltage unbalance protection for capacitor banks. The voltage on the bus issupervised with the voltage in the capacitor bank, phase- by phase. Differenceindicates a fault, either short-circuited or open element in the capacitor bank. It isSection 8 1MRK 505 337-UUS -Voltage protection244Application manual
