GE MI-869 - Page 303

CHAPTER 4: SETPOINTS PROTECTION
869 MOTOR PROTECTION SYSTEM – INSTRUCTION MANUAL 4–185
Figure 4-61: Phase Instantaneous Overcurrent logic diagram
894034A2.cdr
SETPOINTS
Phase A current (Ia)
RUN
SETPOINTS
FUNCTION: Disabled = 0 Trip
PICKUP:
DROPOUT DELAY:
AND
Phase B current (Ib) Phase C current (Ic)
RUN RUN
Operate Output Relay 1 (TRIP)
LED: PICKUP
Alarm
OR
OR
From Cold Load Pickup
From Autoreclose
(per shot settings)
Phase Currents
AND
Latched Alarm
AND
SETPOINTS
BLOCK Off = 0
OR
Ib > PICKUP
Ia > PICKUP
Ic > PICKUP
SETPOINTS
t
PKP
t
PKP
t
PKP
OR
OR
LED: ALARM
RESET
Command
AND
S R
LATCH
Configurable
Phase IOC1 OP
Phase IOC1 OP A Phase IOC1 OP B
Phase IOC1 OP C
FlexLogic Operands
Phase IOC1 PKP
Phase IOC1 PKP A Phase IOC1 PKP B
Phase IOC1 PKP C
FlexLogic Operands
SETPOINTS
OUTPUT RELAYS Do Not Operate, Operate
t
RST
t
RST
t
RST
PICKUP DELAY:
LED: TRIP
Set
Dominant
Ph A Reverse (from Phase
Directional OC element)
From Manual Close
Blocking
SETPOINTS
INPUT: Phasor, RMS
SETPOINTS
DIRECTION: Disabled Forward Reverse
OR
AND AND
Ph B Reverse (from Phase
Directional OC element)
Ph C Reverse (from Phase
Directional OC element)
AND AND
Same Logic as for Phase A Same Logic as for Phase A
CONFIGURABLE IN 845
SETPOINTS
SIGNAL INPUT: CT Bank 1 - J1
USED ONLY IN
845/ 889
USED ONLY IN 850