GE MM300 Instruction Manual page 169

CHAPTER 5: SETPOINTS
NOTE:
NOTE
MM300 MOTOR MANAGEMENT SYSTEM – INSTRUCTION MANUAL
The restart inhibit element may be used to ensure that a certain amount of time passes
between the time a motor is stopped and the restarting of that motor. This timer is useful
for many process applications and motor considerations. If a motor is on a down-hole
pump, the liquid may fall back down the pipe and spin the rotor backwards after the motor
stops. It would be very undesirable to start the motor at this time. This feature is bypassed
by undervoltage immediate restart and by external start.
For each of these features, non-volatile memory is used to make them behave as if they
continue to operate while control power is lost.
While MM300 stays in 'Test Mode', the starting inhibits functions are blocked.
Figure 5-34: Starting duty inhibit setpoints
The following setpoints are available.
[Path: Home > Setpoints > Control > Inhibits]
Start Inhibit Margin
Range: 0 to 10% in steps of 1 or Off
Default: OFF
This setpoint specifies the start inhibit margin. A value of "OFF" disables start inhibits. A
value of 0% causes starts to be inhibited until the thermal capacity used value
calculated by the thermal model drops to 15% or less. Setpoint values in the range of 1
to 10% specify the margin to be included in the calculation of the learned thermal
capacity used at start value, and cause starts to be inhibited until the present thermal
capacity used value drops to the learned thermal capacity used at start value or less.
Starts/Hour Limit
Range: 1 to 5 in steps of 1 or OFF
Default: OFF
This setpoint specifies the number of starts in the last 60 minutes at which count start
control is inhibited. A value of "OFF" defeats this feature.
Time Between Starts
Range: 1 to 3600 seconds in steps of 1 second, or OFF
Default: OFF
This setpoint specifies the time following a start before a start control is permitted to
prevent restart attempts in quick succession (jogging). A value of "OFF" defeats this
feature.
Restart Block Time
Range: 1 to 50000 seconds in steps of 1 second, or OFF
Default: OFF
This setpoint specifies the time following stop before a start control is permitted. A value
of "OFF" defeats this feature.
CONTROL ELEMENTS
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