Cause: PID feedback wire break comes when the PID feedback wire is broken. This alarm is triggered when the feedback signal used in PID control becomes invalid, such as when the feedback signal wire breaks, goes open-circuit, or drops below/above expected range.

cof fault in fuji FRENIC MEGA drive indicates PID feedback wire break. This means a loss of signal from the sensor providing feedback for the drive's internal Proportional-Integral-Derivative (PID) control loop.

• Check whether the PID feedback signal wires are connected correctly.
• Check whether any joint or connecting part bites the wire sheath.