OC1 - Over-current during acceleration:
Acceleration or deceleration may be too fast. Increase the acceleration time (ACC). Also, check the grid voltage. If the VFD's power is insufficient, select a VFD with greater power. Check for short circuits in the load (ground short circuit or wire short circuit), and ensure the motor runs smoothly. Inspect the output configuration and look for strong external interference.

OC2 - Over-current during deceleration:
The grid voltage may be too low, or the VFD's power may not be enough. Check the power supply, and if needed, choose a VFD with greater power. Check for sudden changes or abnormalities in the load, including short circuits or ground faults. Inspect the output configuration.

OC3 - Over-current at constant speed:
Sudden transitions or abnormal conditions in the load may cause this fault. Check for short circuits in the load or phase loss in the output. Look for external disturbances and inspect the output configuration.

OV1 - Over-voltage during acceleration:
Check the input voltage for abnormalities. If there is large energy feedback from the load or if the deceleration time (DEC) is too short, extend it. Consider adding dynamic braking components if the VFD starts while the motor is rotating.

OV2 - Over-voltage during deceleration:
Check the input voltage and ensure the deceleration time is long enough. If the VFD started while the motor was still rotating, you may need to add braking components.

OV3 - Over-voltage at constant speed:
This fault indicates an over-voltage condition at constant speed. Check the input voltage and consider adding dynamic braking components. Also, review energy feedback from the load.

UV - DC bus under-voltage:
Check the power supply voltage. If it is too low, inspect the input power to the VFD.

OL1 - Motor overload:
Possible causes:
   • The power supply voltage is too low.
   • The motor's set rated current is incorrect.
   • The motor has stalled or the load transitions are too strong.
What to do:
   • Check the power supply line.
   • Reset the motor's rated current.
   • Check the load and adjust the torque.

OL2 - VFD overload:
Possible causes:
   • Acceleration is too fast.
   • The motor is restarting after stopping.
   • The power supply voltage is too low.
   • The load is too heavy or the motor power is too small.
What to do:
   • Increase the ACC time.
   • Avoid restarting after stopping.
   • Check the power supply line.
   • Select a VFD with greater power.
   • Choose a proper motor.

OL3 - Electrical overload:
The VFD will report an overload pre-alarm based on the set value.
What to do:
   • Check the load and the overload pre-alarm setting.

OH1 - Rectifier overheated:
Possible causes:
   • The air duct is blocked, or the fan is damaged.
   • Ambient temperature is too high.
   • Overload running time is too long.
What to do:
   • Refer to the overcurrent solution.
   • Clean or replace the air duct or fan.
   • Lower the ambient temperature.
   • Check and reconnect connections if necessary.
   • Replace the power source or main control panel.

OH2 - Inverter module overheated:
Similar causes as OH1. Ensure the fan and cooling system are working properly.
What to do:
   • Replace the fan or check the cooling system.
   • Lower the ambient temperature.
   • Check the power supply and connections.

EF - External fault:
Indicates an error in the external device inputs.
What to do:
   • Check the external device input.

CE - Communication error:
Possible causes:
   • Incorrect baud rate setting.
   • Issues with communication wiring.
   • Incorrect communication address.
   • Strong interference in communication.
What to do:
   • Set the correct baud rate.
   • Check communication connections.
   • Set the correct communication address.
   • Improve anti-interference capabilities.

EEP - EEPROM fault:
This fault indicates an error in the read/write control of the EEPROM parameters or damage to the EEPROM.
What to do:
   • Press the STOP/RST button to reset.
   • Replace the main control panel.

PIDE - PID feedback fault:
This fault indicates the PID feedback is offline or the source is lost.
What to do:
   • Check the PID feedback signal.
   • Check the PID feedback source.

END - Time reach of factory setting:
Indicates that the VFD's running time has exceeded the internally set time.
What to do:
   • Consult the supplier to adjust the running time setting.

LL - Electronic underload fault:
Indicates that the VFD has reported an underload pre-alarm based on the set value.
What to do:
   • Check the load and the underload pre-alarm point.