CHAPTER 10: THEORY OF OPERATION
SINGLE-POLE TRIPPING
L90 LINE CURRENT DIFFERENTIAL SYSTEM – INSTRUCTION MANUAL
10-47
10
Table 10-30: Blocking scheme trip table for four-bit channels
Table 10-31: Unblocking scheme trip table for four-bit channels
1
0
0
0
AG
BC, BCG
Trip Three Phases
0
1
0
0
BG
CA, CAG
0
0
1
0
CG
AB, ABG
0
0
0
1
MULTI-P
Unrecognized
Remote data
Local data
Bit pattern received
Remote determination of
fault type
Local determination of fault
type
Trip output
RX1
RX2
RX3
RX4
0
0
0
0
Any while the INIT signal
was not established
Trip as for single-bit
channel
1
1
1
0
MULTI-P
AG
DIR BLOCK TRIP A
1
0
1
1
BG
AG
1
1
0
1
CG
AG
0
1
1
1
AG
AG, AB, ABG, CA, CAG, 3P,
Unrecognized
1
0
1
1
BG
BG, AB, ABG, BC, BCG, 3P,
Unrecognized
DIR BLOCK TRIP B
0
1
1
1
AG
BG
1
1
0
1
CG
BG
1
1
1
0
MULTI-P
BG
1
1
0
1
CG
CG, BC, BCG, CA, CAG, 3P,
Unrecognized
DIR BLOCK TRIP C
0
1
1
1
AG
CG
1
0
1
1
BG
CG
1
1
1
0
MULTI-P
CG
0
1
1
1
AG
BC, BCG
DIR BLOCK TRIP 3P
1
0
1
1
BG
CA, CAG
1
1
0
1
CG
AB, ABG
1
1
1
0
MULTI-P
Unrecognized
Remote data
Local data
Bit pattern received
Remote
determinatio
n of fault
type
Local determination
of fault type
Trip output
RX1
LOG1
RX2
LOG2
RX3
LOG3
RX4
LOG4
0
0
0
0
0
0
1
1
MULTI-P
AG
DCUB TRIP A
0
0
0
0
0
0
0
1
0
0
1
1
0
0
0
0
BG
0
0
0
1
0
0
0
0
0
0
0
0
1
1
0
0
CG
0
0
0
0
0
1
0
0
1
1
0
0
0
0
0
0
AG
AG, AB, ABG, CA, CAG,
3P, unrecognized
0
1
0
0
0
0
0
0
Remote data
Local data
Bit pattern received
Remote
determination of
fault type
Local determination of fault
type
Trip output
RX1
RX2
RX3
RX4