GE MiCOM P145 Agile - Circuit Breaker Fail Logic; Figure 102: Circuit Breaker Fail Logic - Three Phase Start

4 CIRCUIT BREAKER FAIL LOGIC
V00634
Ext. Trip 3ph
Trip Command In
IA< Start
IB< Start
IC< Start
External Trip EF
IN< Start
External TripSEF
CBF SEF Trip
ISEF< Start
CBF NonI Trip
Volt Prot Reset
I< Only
CB Open & I<
Prot Reset & I<
All Poles Dead
Ext. Trip 3ph
Ext Prot Reset
I<Only
CB Open & I<
Prot Reset & I<
All Poles Dead
ZCD IA<
ZCD IC<
ZCD IB<
ZCD IN<
ZCD IN<
ZCD ISEF<
CBF3PhStart
CB Fail Alarm
1
&
&
1
1
IN< Start
1
1
1
1
&
&
1
&
&
S
R
D
Q
S
R
D
Q
S
RD
Q
S
RD
Q
S
R
D
Q
All latches are reset dominant and are triggered on the positive edge . If
the edge occurs while the reset is active , the detection of the edge is
delayed until the reset becomes non -active.
Note on SR Latches
Figure 102: Circuit Breaker Fail logic - three phase start
P14x Chapter 8 - CB Fail Protection
P14xEd1-TM-EN-1 187