Alarm code: A.Cb0. Alarm Name: Encoder Echo back Error on Sony SI-F209 Electronic Part Mounter

Alarm Display: A.Cb0

Alarm Name: Encoder Echo back Error

Situation at Alarm Occurrence: Occurred when the control power supply was turned ON or during operation.

Cause: The encoder wiring and contact are incorrect.
Corrective Actions: Correct the encoder wiring.

Cause: Noise interference occurred due to incorrect encoder cable specifications.
Corrective Actions: Use tinned annealed copper twisted-pair or twisted-pair shielded wire with a core of at least 0.12 mm (0.0002 in).

Cause: Noise interference occurred because the wiring distance for the encoder cable is too long
Corrective Actions: The wiring distance must be 20m (65.6 ft) max.

Cause: Noise interference occurred on the signal line, because the encoder cable is bent and the sheath is damaged.
Corrective Actions: Correct the encoder cable layout

Cause: The encoder cable is bundled with a high-current line or near a high-current line.
Corrective Actions: Correct the encoder cable layout so that no surge is applied

Cause: The FG varies because of the influence from the servomotor side machines, such as welder.
Corrective Actions: Ground the machine separately from PG side FG.

Cause: Noise interference occurred on the signal line from the encoder.
Corrective Actions: Take measures against noise for the encoder wiring

Cause: Excessive vibration and shocks to the encoder was applied.
Corrective Actions: Reduce the machine vibration or mount the servomotor securely.

Cause: An encoder fault occurred.
Corrective Actions: Replace the servomotor.

Cause: A SERVOPACK board fault occurred
Corrective Actions: Replace the SERVOPACK

Written by: SMTBOX Editorial & Engineering Team

Our editorial team consists of senior SREs, mechanical engineers, and SMT assembly specialists with over 15 years of industry experience in PCB assembly line optimization. All technical articles are reviewed and verified for mechanical and electronic compatibility before publication.