OC1 (0001) - Overcurrent during Acceleration:
+ The acceleration time is too short.
+ The V/F setting is incorrect.
+ A restart signal is sent to the motor after a brief stop.
+ A special motor (e.g., with low impedance) is used.

    Solutions:
+ Increase the acceleration time.
+ Check the V/F parameter.
+ Use F301 (auto-restart) and F302 (ride-through control).
+ Increase the carrier frequency with F303.

OC2 (0002) - Overcurrent during Deceleration:
+ The deceleration time is too short.

    Solutions:
+ Increase the deceleration time.

OC3 (0003) - Overcurrent during Operation:
+ The load fluctuates suddenly.
+ The load is in an abnormal condition.

    Solutions:
+ Reduce load fluctuations.
+ Check the load (operated machine).

OCR (0005) - Arm Overcurrent at Start-up:
+ A main circuit element is defective.

    Solutions:
+ Make a service call.

OCL (0004) - Overcurrent on the Load Side at Start-up:
+ The insulation of the output main circuit or motor is defective.
+ The motor impedance is too low.

    Solutions:
+ Check the cables and wires for defective insulation.

OP1 (000A) - Overvoltage during Acceleration:
+ The input voltage fluctuates abnormally.
+ The power supply has a capacity of 200kVA 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.

    Solutions:
+ Insert a suitable input reactor.
+ Use F301 (auto-restart) and F302 (ride-through control).

OP2 (000B) - Overvoltage during Deceleration:
+ The deceleration time is too short (Regenerative energy is too large).
+ F304 (dynamic braking resistor activation) is off.
+ F305 (overvoltage limit operation) is off.
+ The input voltage fluctuates abnormally.
- The power supply has a capacity of 200kVA or more.
- A power factor improvement capacitor is opened or closed.
- A system using a thyristor is connected to the same power distribution line.

    Solutions:
+ Increase the deceleration time.
+ Install a suitable dynamic braking resistor.
+ Enable F304 (dynamic braking selection).
+ Enable F305 (overvoltage limit operation).
+ Insert a suitable input reactor.

OP3 (000C) - Overvoltage during Constant-Speed Operation:
+ The input voltage fluctuates abnormally.
- The power supply has a capacity of 200kVA or more.
- A power factor improvement capacitor is opened or closed.
- A system using a thyristor is connected to the same power distribution line.
+ If the motor is in a regenerative state, the load causes the motor to run at a frequency higher than the inverter output frequency.

    Solutions:
+ Insert a suitable input reactor.
+ Install a dynamic braking resistor.

OL1 (000D) - Inverter Overload:
+ The acceleration time is too short.
+ The DC braking amount is too low.
+ The V/F setting is incorrect.
+ A restart signal is input to the motor after a momentary stop.
+ The load is too large.

    Solutions:
+ Increase the acceleration time.
+ Reduce the DC braking amount and time.
+ 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 incorrect.
+ The motor is locked up.
+ Low-speed operation is performed continuously.
+ An excessive load is applied to the motor.

    Solutions:
+ Check the V/F parameter setting.
+ Check the load (operated machine).
+ Adjust to a load that the motor can withstand during operation in a low-speed range.

EPHO (0009) - Output Phase Failure:
+ A phase failure occurred in the output line of the main circuit.

    Solutions:
+ Check the main circuit output line, motor, etc., for phase failure.
+ Enable F605 (output phase failure detection).

EPHI (0008) - Input Phase Failure:
+ A phase failure occurred in the input line of the main circuit.

    Solutions:
+ Check the main circuit input line for phase failure.
+ Enable F608 (input phase failure detection).

+ Toshiba S9 User Manual >>

+ Toshiba S9 Fault index >>

+ Toshiba S9 Fault codes 2 >>

+ Toshiba 2 Main page -

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