7.1.6.5 Operating and inhibit conditionsFigure 53 presents a simplified logic diagram for the Power swing detection functionZMRPSB.The load encroachment characteristic can be switched off by setting the parameterOperationLdCh = Off, but notice that the DFw and DRv will still be calculated fromRLdOutFw and RLdOutRv. The characteristic will in this case be only quadrilateral.There are three different ways to form the internal INHIBIT signal:• Logical 1 on functional input BLOCK inhibits the output START signalinstantaneously.• The INHIBIT internal signal is activated, if the power swing has been detectedand the measured impedance remains within its operate characteristic for thetime, which is longer than the time delay set on tR2 timer. It is possible to disablethis condition by connecting the logical 1 signal to the BLKI01 functional input.• The INHIBIT internal signal is activated after the time delay, set on tR1 timer, ifan earth-fault appears during the power swing (input IOCHECK is high) and thepower swing has been detected before the earth-fault (activation of the signalI0CHECK). It is possible to disable this condition by connecting the logical 1signal to the BLKI02 functional input.7.1.7 Technical dataTable 54:ZMRPSB technical dataFunction Range or value AccuracyReactive reach (0.10-3000.00) W/phase ± 2.0% static accuracyConditions:Voltage range: (0.1-1.1) x UrCurrent range: (0.5-30) x IrAngle: at 0 degrees and 85degreesResistive reach (0.10–1000.00) W/phaseTimers (0.000-60.000) s ± 0.5% ± 10 msMinimum operate current (5-30)% of IBase ± 1.0% of Ir7.2 Underimpedance protection for generators andtransformers ZGCPDIS7.2.1 IdentificationFunction description IEC 61850identificationIEC 60617identificationANSI/IEEE C37.2device numberUnderimpedance protection forgenerators and transformersZGCPDIS 21GSection 7 1MRK 504 135-UEN AImpedance protection130Technical manual
