GE Multilin 850

4–112 850 FEEDER PROTECTION SYSTEM – INSTRUCTION MANUAL
PROTECTION CHAPTER 4: SETPOINTS
Figure 4-42: Undercurrent logic diagram
Phase Currents
Phase A Current (Ia)
Phase B Current (Ib)
Phase C Current (Ic)
SETPOINT
Configurable
Trip Function
Disabled
Trip
BKR 1 Closed
FLEXLOGIC OPERAND
SETPOINT
Block
Off=0
AND
Start Block Delay
SETPOINT
t
BLK
0
SETPOINT
Latched Alarm
Alarm Function
Disabled
Alarm
OR
AND
RUN
Trip Pickup
SETPOINT
Trip Pickup Delay
SETPOINTS
Trip Dropout Delay
t
PKP
t
RST
Alarm Pickup Delay
SETPOINTS
Alarm Dropout Delay
t
PKP
t
RST
AND
Operate Output
Relay 1(TRIP)
LED: TRIP
LED: Alarm
AND AND
OR
LATCH
S
R
RESET
Command
Undercur Trip PKP
FLEXLOGIC OPERANDS
Undercur Trip OP
Undercur Alarm PKP
FLEXLOGIC OPERANDS
Undercur Alarm OP
SETPOINT
Trip Output Relay X
Do Not Operate, Operate
SETPOINT
Alarm Output Relay X
Do Not Operate, Operate
OR
I
c
< Trip Pickup
I
b
< Trip Pickup
I
a
< Trip Pickup
OR
RUN
Alarm Pickup
SETPOINT
I
c
< Alarm Pickup
I
b
< Alarm Pickup
I
a
< Alarm Pickup
OR
SETPOINTS
SIGNAL INPUT:
CT Bank 1 - J1
850 Only
894205A1.cdr