Acceleration Protection - GE MM200 Instruction Manual

CHAPTER 4: SETPOINTS
Acceleration
protection
MM200 MOTOR MANAGEMENT SYSTEM – INSTRUCTION MANUAL
Undercurrent Alarm Level
Range: 1 to 100% of FLA or OFF
Default: OFF
This setpoint specifies the undercurrent alarm pickup level. A value of "OFF" disables the
undercurrent alarm function.
Undercurrent Alarm Delay
Range: 1 to 60 seconds in steps of 1
Default: 1 seconds
This setpoint represents the time that the motor current must be below pickup to
generate an alarm.
For example, if a pump is cooled by the liquid it pumps, loss-of-load may mean that the
pump overheats. In this case, the undercurrent feature is enabled. To prevent motor
loading from falling below 0.75 × FLA, even for short durations, the
could be set to "70%" and the
and
Delay Undercurrent Alarm Delay
1 second).
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
Set to Enable if the MM200 should trip when an open control circuit is detected.
to "75%". The
Undercurrent Alarm Level
setpoints are typically set as quick as possible (that is,
PROTECTION ELEMENTS
Undercurrent Trip Level
Undercurrent Trip
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