Inverter IPM Alarm
Fanuc · αi series AC Servo Motor
What does 416 mean?
An Inverter IPM Alarm has been issued, indicating a fault within the Intelligent Power Module (IPM) of the inverter. This is often caused by overheating due to cooling issues, motor overcurrent, high ambient temperatures, or insulation breakdown.
Common Causes
- Cooling fan for the servo amplifier is stopped or malfunctioning.
- Motor is operating beyond its rated current capacity.
- High temperature in the electrical locker or cabinet.
- High ambient temperature around the servo amplifier module.
- Unsatisfactory insulation between ground and motor phases U, V, or W of the servo motor.
- Unsatisfactory insulation within the power line connecting the amplifier to the motor.
Repair Steps
- 1
Verify that the cooling fan of the servo amplifier is operating correctly.
- 2
Check whether the motor is being used within its specified rated current limits.
- 3
Measure the temperature inside the electrical locker and around the servo amplifier module. Inspect and clean any fins or filters in the locker.
- 4
Disconnect the power line from the servo amplifier module connector. Release the emergency stop state. If the IPM alarm continues, replace the servo amplifier module.
- 5
If no IPM alarm is issued after disconnecting power lines from the servo amplifier, check the insulation resistance between ground and each of U, V, and W at the amplifier output terminals.
- 6
If insulation is not satisfactory, disconnect the power line from the servo motor. Check the insulation of the servo motor. If servo motor insulation is not satisfactory, replace the servo motor. If the power line insulation is not satisfactory, replace the servo amplifier module.