GE MI-869 - Page 259

CHAPTER 4: SETPOINTS PROTECTION
869 MOTOR PROTECTION SYSTEM – INSTRUCTION MANUAL 4–141
Figure 4-44: Mechanical Jam logic diagram
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SETPOINT
Configurable FUNCTION:
Disabled=0 Trip Alarm Latched Alarm
OR
SETPOINT
BLOCK: Off=0
IA mag IB mag IC mag
AND
RUN
PICKUP:
SETPOINT
IA > Pickup
IB > Pickup
IC > Pickup
OR
PICKUP DELAY:
SETPOINTS
DROPOUT DELAY:
t
PKP
t
RST
FLEXLOGIC OPERAND
Mechanical Jam PKP
AND AND AND
Operate Output
Relay 1(TRIP)
LED: TRIP
OR
LED: ALARM
LATCH
S R
RESET
Command
FLEXLOGIC OPERAND
Mechanical Jam OP
SETPOINT
OUTPUT RELAY X
Do Not Operate, Operate
Phase Currents Magnitude
from Phase Current CT bank
Motor Starting
FLEXLOGIC OPERAND
From Setpoint > System > Motor > Setup
Speed2 Motor Switch
FLEXLOGIC OPERAND
I
avg
> OL x FLA
MOTOR OVERLOAD FACTOR:
SETPOINTS
SPEED2 MOTOR FLA:
LATCH
S R
RUN
()ICIBIA
avg
I ++´=
3
1
IA RMS IB RMS IC RMS
RMS Phase Currents from
Phase Current CT bank
OR
SETPOINT
FUNCTION:
Disabled=0
AND
From Setpoint > Protection > Motor > Acceleration time
ACCEL TIME FR. SPD 1-2:
SETPOINT
From Setpoint > Protection > Motor > Sped2 Acceleration Time
t
reset
0
AND
Rising Edge
AND
1 sec