1. Check the surface of the motor for damage and deformation.
2. Check whether the motor label meets the requirements.
3. Check the fasteners of the motor to prevent loosening.
4. Check the power supply for lack of phase and run for 5 minutes without load.
5. Measuring insulation resistance with 500V megohm meter. The value of insulation resistance should be treated by drying the stator windings. The drying temperature should not exceed 120 C.
6. Check whether the rotation is flexible or not. If there is any abnormality, it should be excluded.