GE 869 - Page 280

4–148 869 MOTOR PROTECTION SYSTEM – INSTRUCTION MANUAL
PROTECTION CHAPTER 4: SETPOINTS
Figure 4-51: Undercurrent logic diagram
89
$1.cdr
Three Phase Currents
from J1-CT bank
Ia Ib
Ic
SETPOINT
Configurable Trip Function
Disabled Trip
Motor Stopped
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