Acceleration Protection; Open Control Circuit Trip Protection; Electrical Protection - GE MM300 Instruction Manual

CHAPTER 5: SETPOINTS
Acceleration
protection
Open control circuit
trip protection

Electrical protection

MM300 MOTOR MANAGEMENT SYSTEM – INSTRUCTION MANUAL
The thermal model protects the motor under both starting and overload conditions. The
acceleration timer trip may be used to complement this protection. For example, if the
motor always starts in 2 seconds, but the safe stall time is 8 seconds, there is no point
letting the motor remain in a stall condition for the 7 or 8 seconds it would take for the
thermal model to operate. Furthermore, the starting torque applied to the driven
equipment for that period of time could cause severe damage.
If enabled, the acceleration protection will trip if the motor stays in the starting state and
does not reach the running state by the set acceleration time.
The acceleration protection setpoints and logic are described below.
Acceleration Alarm Timer(s)
Range: 0.5 to 250.0 seconds in steps of 0.1 or OFF
Default: OFF
This setpoint specifies the maximum acceleration time before alarming. A value of "OFF"
disables the acceleration protection alarm.
Acceleration Trip Timer(s)
Range: 0.5 to 250.0 seconds in steps of 0.1 or OFF
Default: OFF
This setpoint specifies the maximum acceleration time before tripping. A value of "OFF"
disables acceleration protection tripping.
Open Control Circuit Trip
Range: Enable, Disable
Defines whether an open control circuit condition trips (reset required to clear) or alarms
(no reset required).
Select the Home > Setpoints > Protection > Electrical page to edit the mechanical
protection setpoints.
PROTECTION ELEMENTS
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