Fagor alarm 4112: ERROR 801: Encoder not found (motor feedback)
CNC 8055 SERCOS drive error (DDS) · Fagor DDS drives
What it means
Drive cannot detect any motor-feedback device at X4 although one should be present - typically a wiring/parameter-type mismatch rather than a dead encoder.
Likely causes
- feedback cable unplugged at motor or X4, broken conductors
- GP2 feedback type set wrong (e.g. sinusoidal configured, resolver fitted)
- encoder electronics dead (no identification reply)
Triage note: Verify GP2 against the motor nameplate feedback code BEFORE ordering parts - E801 is frequently a configuration artifact after a drive swap.
Replacement parts
We supply the following units for this alarm — tested, warranty-backed:
- Request a quote →
EEC-SP-x / IECD-x
Motor feedback cable · Primary suspect
- Request a quote →
FXM34.20A (match installed model)
Motor with integral encoder · Common cause
Need the part urgently?
Send us alarm 4112 with your machine details — typical RFQ turnaround is 24–48h.