Fagor alarm 4021: Spindle drive error : <code> (main-spindle qualifier)
CNC 8055 SERCOS drive error (DDS) · Fagor DDS drives
What it means
Qualifier message that attaches the standard error class (4002-4011) to the main spindle specifically. Alone it carries no diagnosis; read the paired class code to know what failed. Its presence proves the fault came from the spindle drive, not an axis module.
Likely causes
- any spindle-drive-reported fault class arriving over Sercos
Triage note: Diagnostic pointer only - act on the accompanying 400x code.
Need the part urgently?
Send us alarm 4021 with your machine details — typical RFQ turnaround is 24–48h.