SV1069 FSSB: CRC Error (Slave) fault in Fanuc drive

SV1069 FSSB: CRC Error (Slave) fault in Fanuc drive

Description

SV1069 is the Slave-side version of the FSSB Optical Error. It means the servo amplifier (Slave) received a data packet from the CNC (Master) but the checksum (CRC) was invalid. The data was corrupted in transit from the CNC to the Drive. This is different from the Master-side error which indicates corruption on the return path.

Cause

• Dirty Input Port: The COP10B (Input) port on the drive is dusty.
• Cable Bend: The fiber optic cable leading into this drive is bent too sharply.
• Previous Drive: The previous drive in the chain (which transmits to this one) has a failing optical transmitter.

Solution

1. Trace Source: The error is happening AT the drive, but the cause is the cable coming INTO it. Trace that cable back to the previous unit (or CNC).
2. Replace Cable: Swap the incoming optical cable.
3. Check Previous Unit: If swapping cables fails, the drive *upstream* might have a weak laser output.