Load Increase Alarm; Auxiliary Undervoltage - GE MM300 Instruction Manual

PROTECTION ELEMENTS

Load increase alarm

Auxiliary
undervoltage
5–46
The load increase alarm is used to alarm abnormal load increases that may indicate
problems with the process. An alarm is enabled only after the acceleration phase is
complete and the motor has entered the running phase, and then only if the current has
fallen below the set pickup or 5 seconds have elapsed. Once enabled, the alarm is
generated when the current exceeds the set pickup, and automatically resets when the
current has subsided.
The following setpoints are available.
Load Increase Alarm Level
Range: 50 to 150% of FLA in steps of 1, or OFF
Default: OFF
This setpoint specifies the load increase alarm pickup level. A value of "OFF" disables the
load increase alarm.
Undervoltage on the motor supply can present problems for both starting and running the
motor. The phase undervoltage element may be used to protect against these problems,
however it requires the 3 × VT input option B card to be installed. The auxiliary
undervoltage element may be used if there is no installed option B card, the relay auxiliary
VT input is derived from the motor supply, and where errors introduced by the control
power transformer can be tolerated.
The following setpoints are available for the auxiliary undervoltage protection element.
Aux Undervoltage Alarm
Range: 60 to 90% of NCV in steps of 1, or OFF
Default: OFF
This setpoint specifies the auxiliary undervoltage alarm level.
Aux Undervoltage Alarm Delay
Range: 1 to 60 seconds in steps of 1
Default: 5 seconds
This setpoint specifies the auxiliary undervoltage alarm delay.
Aux Undervoltage Trip
Range: 60 to 90% of NCV in steps of 1, or OFF
Default: OFF
This setpoint specifies the auxiliary undervoltage trip level.
Aux Undervoltage Trip Delay
Range: 1 to 60 seconds in steps of 1
Default: 5 seconds
This setpoint specifies the auxiliary undervoltage trip delay.
MM300 MOTOR MANAGEMENT SYSTEM – INSTRUCTION MANUAL
CHAPTER 5: SETPOINTS