GE MI-869 - Page 273

CHAPTER 4: SETPOINTS PROTECTION
869 MOTOR PROTECTION SYSTEM – INSTRUCTION MANUAL 4–155
Figure 4-50: Short Circuit logic diagram
894099A2.cdr
SETPOINT
Configurable FUNCTION:
Disabled= 0
Trip
Alarm Latched Alarm
OR
SETPOINT
BLOCK:
Off= 0
IA IB
IC
AND
RUN
PICKUP :
SETPOINT
IA > Pickup
IB > Pickup
IC > Pickup
OR
PICKUP DELAY:
SETPOINTS
DROPOUT DELAY:
t
PKP
t
RST
FLEXLOGIC OPERAND
Short Circuit PKP
AND AND AND
Operate Output
Relay 1(TRIP)
LED: TRIP
OR
LED: ALARM
LATCH
S R
RESET
Command
FLEXLOGIC OPERAND
Short Circuit OP
SETPOINT
Output Relay X
Do Not Operate, Operate
Phase Currents from Phase
Current CT bank
SETPOINT
OVERREACH FILTER:
Off or On
SC RMS Ia
ACTUAL VALUES
SC RMS Ib SC RMS Ic
Metering > Motor > Short Circuit