Fagor alarm 4029: Communication with the drive cannot be established. No response
CNC 8055 SERCOS drive error (DDS) · Fagor DDS drives
What it means
Detected on power-up: a drive expected at a given SERCOSID never answers the CNC. All axes stay stopped with enables removed until communication is established. Verify the ring, addresses and baud rate, then isolate by connecting drives one at a time.
Likely causes
- Drive does not recognize its SERCOS board (hardware error on display)
- Drive hung and needs a power cycle
- Rotary address switch not read correctly at power-up
- Baud rate mismatch between CNC SERSPD and drive QP11
Triage note: Save the SERCOS LOG before swapping hardware.
Replacement parts
We supply the following units for this alarm — tested, warranty-backed:
- Request a quote →
Drive SERCOS interface board
drive · Check if others ruled out
Need the part urgently?
Send us alarm 4029 with your machine details — typical RFQ turnaround is 24–48h.