Fagor alarm 4078: ERROR 305: Protocol error on the interface between the power supply module and the driver
CNC 8055 SERCOS drive error (DDS) · Fagor DDS drives
What it means
Communication errors were detected on the internal bus between the power supply module and the drive modules. The error cannot be reset: after checking wiring the whole servo system must be powered down/up, and Fagor directs persistent cases to service. The CNC stays stopped with enables removed.
Likely causes
- Faulty internal interconnect cable/backplane between PSU and drives
- Defective communication port in PSU or drive
- Noise/grounding issue on the internal link
Replacement parts
We supply the following units for this alarm — tested, warranty-backed:
- Request a quote →
PSU-to-drive internal bus cable
power-supply · Check if others ruled out
- Request a quote →
PS / XPS power supply
power-supply · Check if others ruled out
Need the part urgently?
Send us alarm 4078 with your machine details — typical RFQ turnaround is 24–48h.