Cause : PID signal fault comes when the inverter trips if the measured value exceeds the PID upper limit or PID lower limit parameter setting, or the absolute deviation value exceeds the PID deviation parameter setting during PID control. Set this function in Pr.131 PID upper limit, Pr.132 PID lower limit, Pr.553 PID deviation limit, and Pr.554 PID signal operation selection.

1. Check the meter for a failure or break.
2. Check that the parameter settings are correct.
3. Check that the meter has no failure or break.
4. Set the parameters correctly.