Code

Name

Causes

Possible Solutions

PF

Input Phase Loss

There is a phase loss in the drive input power.

Correct all wiring errors with the main circuit power supply.

Loose wiring in the input power terminals.

Tighten the screws to the correct tightening torque.

The drive input power voltage is changing too much.

  • Examine the supply voltage for problems.

  • Make the drive input power stable.

Unsatisfactory balance between voltage phases.

  • Examine the supply voltage for problems.

  • Make the drive input power stable.

  • If the supply voltage is good, examine the magnetic contactor on the main circuit side for problems.

The main circuit capacitors have become unserviceable.

  • Examine the capacitor maintenance time in monitor U4-05 [CapacitorMaintenance].

  • If U4-05 is more than 90%, replace the capacitor. Contact Yaskawa or your nearest sales representative for more information.

  • Examine the supply voltage for problems.

  • Re-energize the drive.

  • If the alarm stays, replace the circuit board or the drive. Contact Yaskawa or your nearest sales representative for more information.
Note:

  • The drive detects this error if the DC bus voltage changes irregularly without regeneration.

  • If the drive detects this error, the terminal set to H2-01 to H2-04 = 10 [MFDO Function Select = Alarm] will be ON.

  • Use L8-05 [Input Phase Loss Protection Sel] to enable and disable PF detection.