Fanuc alarm SP9055: ABNORMAL SPINDLE SWITCHING CONTROL
spindle alarm (serial spindle, alpha i) · Fanuc 0i-D
What it means
The spindle switching control sequence behaved abnormally: the commanded changeover between motor windings, output stages or clutched spindle heads did not follow the legal state progression. The amplifier interlocks rather than energize through an undefined state.
Likely causes
- Contactor feedback contacts not tracking commands
- PMC ladder timing outside the permitted switch-over window
- Worn switching contactors
Need the part urgently?
Send us alarm SP9055 with your machine details — typical RFQ turnaround is 24–48h.