Toshiba VF-AS1 fault codes

Understanding Troubles with Your Toshiba VFD:


   Motor Runs in the Wrong Direction:

 Cause: The phases of the output terminals U, V, and W might be inverted.

 Solution: Swap the connections of any two of the output terminals to correct the motor's direction.


   Motor Speed Doesn't Change Normally:

 Cause: The load might be too heavy, or the soft stall function could be activated.

 Solution: Reduce the load or switch off the soft stall function to allow normal speed changes.


   Motor Doesn't Accelerate or Decelerate Smoothly:

 Cause: The acceleration or deceleration time might be set too short.

 Solution: Increase the acceleration or deceleration time for smoother transitions.


   Motor Runs at Incorrect Speed:

 Cause: This could be due to an improper voltage rating, incorrect frequency settings, or issues with the reduction gear ratio.

 Solution: Use a motor with the correct voltage rating, check the frequency settings, and adjust the gear ratio as needed.


   Motor Speed Varies During Operation:

 Cause: The load might be too heavy or too light, or the inverter/motor rating might not be sufficient.

 Solution: Adjust the load and ensure that the inverter and motor have appropriate ratings for the application.


   Control Panel Issues:

 Cause: Some keys on the operation panel might not work, or you might be unable to change parameter settings.

 Solution: Check the panel operation prohibition parameter and ensure that key operation is allowed.


   Overcurrent During Acceleration (OC1 - OCP1P):

 Cause: This can happen if the acceleration time is too short or the V/f setting is improper.

 Solution: Increase the acceleration time and check the V/f parameter settings.


   Overcurrent During Deceleration (OC2-OC2P):

 Cause: The deceleration time might be too short.

 Solution: Increase the deceleration time to reduce the risk of overcurrent.


   Overcurrent During Fixed Speed (OC3-OC3P):

 Cause: Sudden load fluctuations or abnormal load conditions can cause this.

 Solution: Reduce load fluctuations and check the load for any abnormalities.


   Phase Short Circuits (OCA1, OCA2, OCA3):

 Cause: There could be a defect in the main circuit elements of the U, V, or W phase.

 Solution: Contact your Toshiba distributor for assistance.


   Overheating (OH):

 Cause: The cooling fan might not be working, the ambient temperature could be too high, or there could be blockages in the vent.

 Solution: Ensure the cooling fan is operational, maintain an appropriate ambient temperature, and clear any vent blockages.


   Inverter Overload (OL1):

 Cause: Rapid acceleration or a too large DC braking amount can overload the inverter.

 Solution: Increase the acceleration time and reduce the DC braking amount.


   Motor Overload (OL2):

 Cause: The V/f parameter might be set improperly, or the motor could be locked up.

 Solution: Check and adjust the V/f parameter settings and ensure the motor is not locked.


   Overvoltage During Acceleration (OP1):

 Cause: Abnormal fluctuations in input voltage can cause overvoltage.

 Solution: Use an input reactor and check the settings for auto-restart and regenerative power ride-through control.


   Emergency Stop (E):

 Cause: The inverter is stopped by a panel operation or an external control device.

 Solution: Reset the inverter to resume operation.


   EEPROM Errors (EEP1, EEP2, EEP3):

 Cause: These errors occur due to data writing errors or corrupted internal data.

 Solution: Turn off the inverter and then turn it back on. If the error persists, contact your Toshiba distributor.


   Ground Fault (EF1, EF2):

 Cause: A current has leaked from an output cable or the motor to the ground.

 Solution: Check the cable and the motor for ground faults and repair as necessary.


+ VF-AS1 User manual

+ VF-As1 Fault codes

+ Toshiba Main page

++ VFD Main page


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