OC Over Current: ASD output current is higher than the F601 setting.

- Defective IGBT (U, V, or W).
- Incorrect motor connection at the ASD output. Disconnect the motor and retry.
- Phase-to-phase short at the ASD output.
- The ASD is starting into a spinning motor.
- Motor/machine jammed.
- Mechanical brake engaged while the ASD is starting or running.
- Acceleration/Deceleration time is too short.
- Voltage Boost setting is too high.
- Load fluctuations.
- The ASD is operating at an elevated temperature.
    Solutions:
- Check and replace IGBTs if necessary.
- Ensure motor connections are correct.
- Check for short circuits.
- Stop the motor and restart it.
- Adjust acceleration and deceleration times.
- Reduce the Voltage Boost setting.
- Minimize load fluctuations.
- Operate the ASD in a cooler environment.

OH Overheat: The ASD ambient temperature is too high.

- The ASD is operating at a high temperature.
- The ASD is too close to heat-generating equipment.
- Cooling fan vent is obstructed.
- The cooling fan is inoperative.
- The internal thermistor is disconnected.
    Solutions:
- Operate the ASD in a cooler environment.
- Keep the ASD away from heat-generating equipment.
- Clear any obstructions from the cooling fan vent.
- Ensure the cooling fan is working.
- Check internal thermistor connections.

OJ Timer: Run-time counter exceeded.

- Run-time counter is full.
    Solutions:
- Reset is required; select Clear Run Timer.

*OLI ASD Overload: The load requirement exceeds the capability of the ASD.

- The carrier frequency is too high.
- Excessive load.
- Acceleration time is too short.
- DC damping rate is set too high.
- The motor is starting into a spinning load after a momentary power failure.
- The ASD is improperly matched to the application.
    Solutions:
- Reduce the load.
- Adjust the carrier frequency and acceleration times.
- Decrease the DC damping rate.
- Ensure the motor is properly stopped before restarting.
- Verify the ASD is properly matched to the application.

OLM Motor Overload: The load requirement exceeds the capability of the motor.

- Improper V/f parameter setting.
- Motor is locked.
- Continuous operation at low speed.
- The load exceeds what the motor can deliver.
    Solutions:
- Adjust the V/f parameters.
- Ensure the motor is not locked.
- Limit continuous operation at low speeds.
- Reduce the load.

*OLR Resistor Overload: Excessive current at the Dynamic Braking Resistor.

- Deceleration time is too short.
- Improper DBR configuration.
    Solutions:
- Extend the deceleration time.
- Check and adjust the DBR settings.

*OP Overvoltage: DC bus voltage exceeds specifications.

- The ASD is attempting to start into a spinning motor after a momentary power loss.
- Incoming utility power is above the specified range.
- Deceleration time is too short.
- Voltage spikes at the 3-phase input; install an inductive filter.
- DBR required.
- DBR resistance value is too high.
- DBR function is turned off.
- Overvoltage Stall feature is turned off.
- The system is regenerating.
- Load instability.
- Disable the Ridethrough function (F302).
    Solutions:
- Check incoming power levels.
- Adjust deceleration times.
- Install an inductive filter.
- Verify and adjust DBR settings and function.

OT Overtorque: Torque requirement exceeds the setting of F616 or F617 for longer than the setting of F618.

- The ASD is not correctly matched to the application.
- F616 or F617 setting is too low.
- Obstructed load.
    Solutions:
- Ensure the ASD is properly matched to the application.
- Increase the F616 and F617 settings.
- Ensure the load is free and not obstructed.

*POFF Control Undervoltage: Undervoltage condition at the 5, 15, or 24 VDC supply.

- Defective control board.
- Excessive load on the power supply.
- Low input voltage.
    Solutions:
- Check and replace the control board if necessary.
- Reduce the load on the power supply.
- Check and stabilize the input voltage.

PtSt Reference Point: Two speed-reference frequency setpoint values are too close to each other.

- Two speed reference frequency setpoints are too close.
    Solutions:
- Increase the difference between the speed reference frequencies.

UC Undercurrent: The output current of the ASD is below the level defined at F611 and remains there for the time set at F612.

- Insufficient load.
    Solutions:
- Check the load and ensure the motor is properly functioning.

Control Power Undervoltage

- Undervoltage condition at the 5, 15, or 24 VDC supply.
- Low 3-phase input voltage.
    Solutions:
- Check supply voltages and ensure they are not low.
- Check the 3-phase input voltage and ensure it is within the required range.

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