OC1 0001 Overcurrent during acceleration

- The acceleration time ACC is too short.
- The V/F setting is improper.
- A restart signal is input to the rotating motor after a momentary stop, etc.
- A special motor (e.g., motor with a small impedance) is used.
- Low inductance motor especially High speed motor is used.
+ Remedy:
- Increase the acceleration time ACC.
- Check the V/F parameter.
- Use F301 (auto-restart) and F302 (ride-through control).
- In case of P3, P2, and P1, increase b.
- In case of P2 to P1, set F415 (Motor rated current) and make an auto-tuning.
- Choose the higher power range drive (1 class up drive is recommended).

OC2 0002 Overcurrent during deceleration

- The deceleration time DEC is too short.
- Low inductance motor especially High speed motor is used.
+  Remedy:
- Increase the deceleration time DEC.
- Choose the higher power range drive (1 class up drive is recommended).

OC3 0003 Overcurrent during constant speed operation

- The load fluctuates abruptly.
- The load is in an abnormal condition.
- Low inductance motor especially High speed motor is used.
+ Remedy:
- Reduce the load fluctuation.
- Check the load (operated machine).
- Choose the higher power range drive (1 class up drive is recommended).

OC4 0004 Overcurrent (An overcurrent on the load side at start-up)

- The insulation of the output main circuit or motor is defective.
- The motor has too small impedance.
    Remedy:
- Check the secondary wiring and insulation state.
- Set F513=2.3.

OCR Arm overcurrent at start-up

- A main circuit element is defective.
+ Remedy:
- Contact your Toshiba distributor.

EPH1 0008 Input phase failure

- A phase failure occurred in the input line of the main circuit.
- The capacitor in the main circuit lacks capacitance.
+ Remedy:
- Check the main circuit input line for phase failure.
- Check the capacitor in the main circuit for lack of capacitance.

EPH0 0009 Output phase failure

- A phase failure occurred in the output line of the main circuit.
+ Remedy:
- Check the main circuit output line, motor, etc., for phase failure.
- Select output phase failure detection parameter F605.

OP1 000A Overvoltage during acceleration

- The input voltage fluctuates abnormally.
- The power supply has a capacity of 500kVA or more.
- A power factor improvement capacitor is opened or closed.
- A system using a thyristor is connected to the same power distribution line.
- A restart signal is input to the rotating motor after a momentary stop, etc.
+ Remedy:
- Use F301 (auto-restart) and F302 (ride-through control).

OP2 000B Overvoltage during deceleration

- The deceleration time DEC is too short. (Regenerative energy is too large.)
- The input voltage fluctuates abnormally.
- The power supply has a capacity of 500kVA or more.
- A power factor improvement capacitor is opened or closed.
- A system using a thyristor is connected to the same power distribution line.
+ Remedy:
- Increase the deceleration time DEC.
- Set overvoltage limit operation F305 is set to 1. (Disabled).
- Insert a suitable input reactor.

OP3 000C Overvoltage during constant-speed operation

- The input voltage fluctuates abnormally.
- The power supply has a capacity of 500kVA or more.
- A power factor improvement capacitor is opened or closed.
- A system using a thyristor is connected to the same power distribution line.
- The motor is in a regenerative state because the load causes the motor to run at a frequency higher than the inverter output frequency.
+ Remedy:
- Insert a suitable input reactor.
- Install an optional dynamic braking module.

OL1 000D Inverter overload

- The acceleration time ACC is too short.
- The DC braking amount is too large.
- The V/F setting is improper.
- A restart signal is input to the rotating motor after a momentary stop, etc.
- The load is too large.
+ Remedy:
- Increase the acceleration time ACC.
- Reduce the DC braking amount F251 and the DC braking time F252.
- Check the V/F parameter setting.
- Use F301 (auto-restart) and F302 (ride-through control).
- Use an inverter with a larger rating.

OL2 000E Motor overload

- The V/F setting is improper.
- The motor is locked up.
- Low-speed operation is performed continuously.
- An excessive load is applied to the motor during operation.
+ Remedy:
- Check the V/F parameter setting.
- Check the load (operated machine).
- Adjust OL1 to the overload that the motor can withstand during operation in a low-speed range.

OL3 003E Main module overload

- The carrier frequency is high and load current has increased at low speeds (mainly at 15Hz or less).
    Remedy:
- Raise the operation frequency.
- Reduce the load.
- Reduce the carrier frequency.
- When an operating motor is started up at 0Hz, use the auto-tuning function.
- Set carrier frequency control mode selection F36 to 1 (carrier frequency within the auto-tuning operation).

+ VF-MB1 User manual  

+ VF-MB1 Fault index 

+ VF-MB1 Fault codes 1 >>

+ VF-MB1 Fault codes 2 >>

+ VF-MB1 Fault codes 3 >> 

+ Toshiba VF-MB1 -

+ Toshiba Main page  

++ VFD Main page  

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