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469 Motor Management Relay
GE Power Management
4.8 S7 MOTOR STARTING
4 SETPOINT PROGRAMMING
4
4.8.4 RESTART BLOCK
The Restart Block feature may be used to ensure that a certain amount of time passes between stopping a
motor and restarting that motor. This timer feature may be very useful for some process applications or motor
considerations. If a motor is on a down-hole pump, after the motor stops, the liquid may fall back down the pipe
and spin the rotor backwards. It would be very undesirable to start the motor at this time. In another scenario, a
motor may be driving a very high inertia load. Once the supply to the motor is disconnected, the rotor may con-
tinue to turn for a long period of time as it decelerates. The motor has now become a generator and applying
supply voltage out of phase may result in catastrophic failure.
The Restart Block feature is strictly a timer. The 469 does not sense rotor rotation.
y
RESTART BLOCK
y
[ENTER] for more
RESTART BLOCK:
Off
Range: On, Off
RESTART BLOCK
TIME: 1 s
Range: 1 to 50000 sec., step 1
ENTER
ESCAPE
ð
ð
MESSAGE
ESCAPE
NOTE