How can resolve problem A0501 Current limit alarm in siemens micromaster 420 or MM420 drive ?
Cause : Current limit.
- the motor power rating does not correspond to the inverter power rating
- motor cables are too long
- ground fault
Diagnosis & Remedy
Please check the following:
- does the motor power rating (P0307) match the inverter power rating (r0206) ?
- are the limit values for the cable lengths maintained ?
- does the motor cable or motor have a short-circuit or ground fault ?
- do the motor parameters correspond to those of the motor being used ?
- stator resistance value (P0350) correct ?
- is the motor overloaded or is the rotor locked (cannot rotate) ?
- ramp-up time P1120 too low ?
1. Check whether the motor power corresponds to the inverter power
2. Check that the cable length limits have not been exceeded
3. Check motor cable and motor for short- circuits and earth faults
4. Check whether the motor parameters correspond with the motor being used
5. Check the stator resistance
6. Increase the ramp-up-time
7. Reduce the boost
8. Check whether the motor is obstructed or overloaded