Causes

Possible Solutions

There is no PID feedback input.

  • Examine the MFAI terminal settings.

  • See if H3-02, H3-10, H3-06 = B [MFAI Function Select = PID Feedback] is set.

  • Make sure that the MFAI terminal settings agree with the signal inputs.

  • Examine the connection of the feedback signal.

  • Make sure that b5-xx [PID Control] is set correctly.

    Note:

    If there is no PID feedback input to the terminal, the detected value is 0, which causes a PID fault and also causes the drive to operate at maximum frequency.

The detection level and the target value do not agree.

Use H3-03, H3-11, H3-07 [Terminal A1, A2, A3 Gain Setting] to adjust PID target and feedback signal scaling.

Note:

PID control keeps the difference between the target value and detection value at 0. Set the input level for the values relative to each other.

Reverse drive output frequency and speed detection. When output frequency increases, the sensor detects a speed decrease.

Set b5-09 = 1 [PID Output Level Selection = Reverse output (reverse acting)].