Table 37:GENPDIF (87G) Group settings (advanced)Name Values (Range) Unit Step Default DescriptionEndSection1 0.20 - 1.50 IB 0.01 1.25 End of section 1, multiple of generator ratedcurrentEndSection2 1.00 - 10.00 IB 0.01 3.00 End of section 2, multiple of generator ratedcurrentSlopeSection2 10.0 - 50.0 % 0.1 40.0 Slope in section 2 of operate-restraincharacteristic, in %SlopeSection3 30.0 - 100.0 % 0.1 80.0 Slope in section 3 of operate-restraincharacteristic, in %NegSeqROA 30.0 - 120.0 Deg 0.1 60.0 Operate Angle of int/ext neg. seq. faultdiscriminator, degHarmDistLimit 5.0 - 100.0 % 0.1 10.0 (Total) relative harmonic distorsion limit,percentOpCrossBlock NoYes- - Yes Operation Enable/ Disable for cross-blocklogic between phasesAddTripDelay 0.000 - 60.000 s 0.001 0.100 Additional trip delay, when inputraisePickUp=1OperDCBiasing DisabledEnabled- - Disabled Operation DC biasing On / OffOpenCTEnable DisabledEnabled- - Disabled Enable/Disable open CT detectiontOCTAlarmDelay 0.100 - 10.000 s 0.001 1.000 Open CT: time to alarm if an open CT isdetected, in sectOCTResetDelay 0.100 - 10.000 s 0.001 0.250 Reset delay in s. After delay, diff. function isactivatedtOCTUnrstDelay 0.100 - 100.000 s 0.001 10.000 Unrestrained diff. protection blocked after thisdelay, in sTempIdMin 1.0 - 5.0 IdMin 0.1 2.0 Temp. Id pickup when input raisePickUp=1,multiple of IdMinTable 38:GENPDIF (87G) Non group settings (basic)Name Values (Range) Unit Step Default DescriptionGlobalBaseSel 1 - 6 - 1 1 Selection of one of the Global Base Valuegroups6.3.6 Operation principleThe task of Generator differential protection GENPDIF (87G) is to determine whethera fault is within the protected zone, or outside the protected zone. The protected zone isdelimited by the position of current transformers, as shown in figure 46.1MRK 502 043-UUS B Section 6Differential protection117Technical Manual
