F30011Fault · Power unit (Motor Module)Usually repairable
SINAMICS S120 F30011: Power Unit Line Phase Failure In Main Circuit
What F30011 means
The power unit detected a missing or unbalanced supply phase, seen as excessive ripple on the DC link.
Symptoms
Trips under load but may run fine unloaded or at low speed.
Is it repairable?
Yes, when capacitors or the rectifier inside the module are the cause.
Common causes
- Blown fuse or loose terminal on one phase
- Worn main contactor contact
- Unbalanced supply
- Aged DC link capacitors or a failing rectifier
Safe checks
- 1Measure all three phases at the drive input while the machine is under load
- 2Inspect the contactor and fuses
Drives hold dangerous voltage after power-off. Checks should only be done by qualified personnel, with power isolated and the DC link discharged.
Reviewed by AutomIQ repair technicians. Code and name from the SINAMICS S120/S150 List Manual.
Related SINAMICS S120 faults
- F07011Motor overtemperature
- F07900Motor blocked/speed controller at its limit
- F30001Overcurrent
- F30002DC link voltage overvoltage
- F30003DC link voltage undervoltage
- F30004Overtemperature heat sink AC inverter