How to measure the quality of three-phase asynchronous motor

The quality of the three-phase asynchronous motor can be measured by the following methods:

Check with a multimeter. A multimeter can be used to detect the resistance between the three windings of the motor, and its value should be basically equal and not zero. At the same time, check the insulation resistance between each winding and the shell, which is required to be above 0.5MΩ.

Measure with insulation resistance meter. The insulation resistance of the motor to the ground and the insulation resistance between the two phases of the motor are measured respectively, and the insulation resistance value should not be less than 1 megohm at 120 RPM.

No-load running test. The no-load running test can accurately measure the resistance of the motor winding through the single-arm bridge. If the resistance value deviation is large, the motor may be faulty.

Short circuit test. The motor is short-circuit tested under the rated voltage, the short-circuit current of the motor is observed, and the coil of the motor is judged whether there is an inter-turn short circuit according to the current value.

Auscultation test. Close the ear to the motor, carefully listen to its sound, if you hear a noise, it indicates that the motor is faulty.

The current test. Test the working current of the motor with a clamp ammeter to observe whether the current exceeds the rated current, if it exceeds the rated current, it indicates that the motor is faulty.

The above methods are common methods for detecting the quality of three-phase asynchronous motors, and the appropriate method is selected for measurement according to the specific situation.