How to identify the BLDC new motor is good or bad without connect to power supply electricity

How to identify the BLDC new motor is good or bad without connect to power supply？

There are three ways

1. Use the universal meter to measure DC resistance of the three phase winding,

   If the difference of resistance more than 10%, the resistance of a small phase may have

    inter-turn short circuit.

2. Use 500v insulation shake table to measure three-phase winding phase insulation resistance and

   on the ground  (to the case) insulation resistance,a long-term storage motor insulation resistance

   more than  0.5 megohms is considered as a good motor,

   If resistance is between 0.1 megohms and 0.5 megohms the motor has damp,

   before use it should be dried,

   If Insulation resistance is very low that insulation has been damaged.

3. Rotate the motor rotor, it should be easy and free from noise and friction,

    indicating normal bearing and air gap.