Siemens alarm F30314: Power unit: 24 V power supply overloaded by PM
SINAMICS S120 drive fault · SINAMICS S120
What it means
The Power Module draws too much current through its 24 V feed because no external 24 V supply is connected at X124 of the Control Unit. Booksize/chassis setups rely on that external feed for the electronics supply; powering everything through the PM's internal path overloads it. Connecting an external 24 V source to X124 resolves the condition without hardware change.
Likely causes
- external 24 V supply at CU X124 not connected
- X124 wiring open or fuse blown
- undersized external PSU unable to carry the bus load
Need the part urgently?
Send us alarm F30314 with your machine details — typical RFQ turnaround is 24–48h.