Name Type Description
PU_A BOOLEAN Pickup signal from phase A
PU_B BOOLEAN Pickup signal from phase B
PU_C BOOLEAN Pickup signal from phase C
BLK2H BOOLEAN Block signal due to second harmonic
BLK2H_A BOOLEAN Block signal due to second harmonic phase A
BLK2H_B BOOLEAN Block signal due to second harmonic phase B
BLK2H_C BOOLEAN Block signal due to second harmonic Phase C
BLK5H BOOLEAN Block signal due to fifth harmonic
BLK5H_A BOOLEAN Block signal due to fifth harmonic phase A
BLK5H_B BOOLEAN Block signal due to fifth harmonic phase B
BLK5H_C BOOLEAN Block signal due to fifth harmonic phase C
OPENCT BOOLEAN An open CT was detected
ALARM BOOLEAN Alarm for sustained differential current
OPENCTAL BOOLEAN Open CT Alarm output signal. Issued after a delay ...
ID_A REAL Instantaneous differential current, phase A
ID_B REAL Instantaneous differential current, phase B
ID_C REAL Instantaneous differential current, phase C
IDMAG_A REAL Magnitude of fund. freq. differential current, phase A
IDMAG_B REAL Magnitude of fund. freq. differential current, phase B
IDMAG_C REAL Magnitude of fund. freq. differential current, phase C
IBIAS REAL Magnitude of the bias current, common for phase A,B.C
IDMAG_NS REAL Magnitude of the negative sequence differential current
Table 66: LT6CPDIF (87LT) Input signals
Name
Type Default Description
I3P1 GROUP
SIGNAL
- Three phase current grp1 samples and DFT values
I3P2 GROUP
SIGNAL
- Three phase current grp2 samples and DFT values
I3P3 GROUP
SIGNAL
- Three phase current grp3 samples and DFT values
I3P4 GROUP
SIGNAL
- Three phase current grp4 samples and DFT values
I3P5 GROUP
SIGNAL
- Three phase current grp5 samples and DFT values
I3P6 GROUP
SIGNAL
- Three phase current grp6 samples and DFT values
Section 5 1MRK505222-UUS C
Differential protection
148
Technical reference manual