Name Values (Range) Unit Step Default Description
RatVoltW1TraB 1.0 - 9999.9 kV 0.1 130.0 Transformer B rated voltage (kV) on winding
1 (HV winding)
RatVoltW2TraB 1.0 - 9999.9 kV 0.1 130.0 Transformer B rated voltage (kV) on winding
2 (LV winding)
ClockNumTransB 0 [0 deg]
1 [30 deg lag]
2 [60 deg lag]
3 [90 deg lag]
4 [120 deg lag]
5 [150 deg lag]
6 [180 deg lag]
7 [210 deg lag]
8 [240 deg lag]
9 [270 deg lag]
10 [300 deg lag]
11 [330 deg lag]
- - 0 [0 deg] Transf. B phase shift in multiples of 30 deg, 2
for 60 deg
ZerSeqPassTraB No
Yes
- - No Yes/No for capability of transf B to transform
zero seq curr
Table 79: LT6CPDIF (87LT) Group settings (basic)
Name Values (Range) Unit Step Default Description
Operation Disabled
Enabled
- - Disabled Disable/Enable Operation
IdMin 0.20 - 2.00 IB 0.01 0.30 Oper - restr charact., section 1 sensitivity,
multiple IBase
IdMinHigh 0.20 - 10.00 IB 0.01 0.80 Initial lower sensitivity, as multiple of IBase
tIdMinHigh 0.000 - 60.000 s 0.001 1.000 Time interval of initial lower sensitivity, in sec
IdUnre 1.00 - 50.00 IB 0.01 10.00 Unrestrained differential current limit, multiple
of IBase
NegSeqDiffEn Disabled
Enabled
- - Enabled Off/On selection for internal / external fault
discriminator
NegSeqROA 30.0 - 120.0 Deg 1.0 60.0 Internal/external fault discriminator Operate
Angle, degrees
IMinNegSeq 0.01 - 0.20 IB 0.01 0.04 Min. value of neg. seq. curr. as multiple of
IBase
CrossBlockEn No
Yes
- - No Off/On selection of the cross -block logic
I2/I1Ratio 5.0 - 100.0 % 1.0 10.0 Max. ratio of second harmonic to fundamental
harm dif. curr. in %
I5/I1Ratio 5.0 - 100.0 % 1.0 25.0 Max. ratio of fifth harmonic to fundamental
harm dif. curr. in %
ChargCurEnable Disabled
Enabled
- - Disabled Off/On selection for compensation of
charging currents
AddDelay Disabled
Enabled
- - Disabled On/Off selection for delayed diff. trip command
Table continues on next page
1MRK505222-UUS C Section 5
Differential protection
157
Technical reference manual