Common faults and solutions of variable frequency motors

1. The motor cannot start

Possible reasons:
Power failure or power not connected.
Parameter setting error.
External control signal issue.

terms of settlement:
Check if the power supply is functioning properly and ensure that it is connected.
Check the parameter settings of the frequency converter to ensure compatibility with the motor.
Check if the external control signals are normal, such as PLC or other control devices.

2. Overcurrent

Possible reasons:
Motor overload.
Short circuit on the output side.
Internal malfunction of the frequency converter.

terms of settlement:
Check if the load is too large, reduce the load or increase the power.
Check if there is a short circuit or poor contact in the output side circuit.
If there is suspicion of an internal fault in the frequency converter, it is necessary to contact professional maintenance personnel for inspection and repair.

3. Overvoltage

Possible reasons:
The input voltage is too high.
The deceleration time is set too short.

terms of settlement:
Use voltage stabilizing equipment to ensure that the input voltage is within the normal range.
Increase the deceleration time to gradually reduce the speed of the motor before stopping.

4. Abnormal regeneration

Possible reasons:
Damaged or poorly wired braking resistor.
Excessive regenerative energy.

terms of settlement:
Check if the braking resistor is damaged, and replace it promptly if there are any issues.
Check if the wiring of the braking resistor is secure, ensuring no looseness or poor contact.
If the regenerative energy is too large, consider increasing the capacity of the braking resistor or adjusting the regenerative energy processing method of the frequency converter.

5. Motor shaking, whistling, and heating

Possible reasons:
The motor does not match the frequency converter.
Improper parameter settings.
Motor malfunction.

terms of settlement:
Check if the motor matches the frequency converter, including power, voltage, and carrier frequency.
Readjust the parameters of the frequency converter, such as the PI regulator.
Check if the motor is faulty, such as bearing wear, coil issues, etc. Replace the motor if necessary.

6. The motor fan is not turning

Possible reasons:
The fan is damaged.
The circuit for controlling the fan is faulty.

terms of settlement:
Replace the damaged fan.
Check the circuit that controls the fan to ensure it is unobstructed and free from short circuits or open circuits.

7. The panel does not display

Possible reasons:
The display screen is damaged.
Insufficient or disconnected power supply to the display panel.

terms of settlement:
Replace the display screen.
Check the power supply circuit of the display panel to ensure that the power supply is normal, without any disconnection or poor contact.

8. Inverter output phase loss

Possible reasons:
The wiring on the output side is loose.
The power device on the output side is damaged.

terms of settlement:
Check and tighten the wiring on the output side.
Replace damaged power devices.

9. Communication interruption of frequency converter

Possible reasons:
The communication line is disrupted.
Loose or damaged communication interface.

terms of settlement:
Check the communication line to ensure it is far away from interference sources.
Tighten or replace the communication interface.

10. Inverter parameter setting error

Possible reasons:
Improper operation by the user when setting parameters.

terms of settlement:
According to the instruction manual of the frequency converter, check and correct the parameter settings.
Do not modify easily without understanding the specific parameter meanings.

11. Internal overheating of the frequency converter

Possible reasons:
Cooling fan malfunction.
Poor ventilation or high ambient temperature.

terms of settlement:
Check and replace the cooling fan.
Improve ventilation conditions and reduce environmental temperature.

12. Abnormal power input

Possible reasons:
The input power supply is unstable or the voltage is too low/too high.
Input side phase loss.

terms of settlement:
Use voltage stabilizing equipment to ensure stable input power supply.
Check and fix the phase loss issue on the input side.

13. Electromagnetic interference (EMI) problem

Possible reasons:
There is strong electromagnetic field interference near the frequency converter.

terms of settlement:
Add shielding measures, such as using shielded cables.
Keep the frequency converter away from strong electromagnetic interference sources.

14. Frequent tripping of frequency converter

Possible reasons:
Overload protection action.
The input side power supply is abnormal.

terms of settlement:
Check if the load is too large, reduce the load or increase the power.
Check the input side power supply to ensure stability and reliability.

15. Inverter alarm code display

Possible reasons:
An internal fault occurs in the frequency converter, which is indicated by an alarm code.

terms of settlement:
Refer to the frequency converter manual based on the alarm code, understand the cause of the fault, and take corresponding solutions.