When a short circuit fault occurs between turns of the motor stator winding, it is generally judged by measuring the DC .

However, the DC resistance of the stator winding of a motor with a large capacity is very small, and will be affected by the relationship between instrument accuracy and measurement error . It is not easy to obtain correct judgment results. The following method can be used to judge.

Fault diagnosis method:

Instead of disassembling the motor, use a single-phase auto-voltage regulator with appropriate capacity to gradually increase the voltage from scratch and introduce low-voltage alternating current to one of the phases. At the same time, use a clamp ammeter to measure the current, so that the current rises to about 1/3 of the rated current of the motor.

Then, stop boosting and use a multimeter to measure the induced voltages of the other two phases. If one phase has an inter-turn short circuit fault, its induced voltage will be lower than the other phase. Switch one phase of power supply and measure the induced voltage of the other two phases in the same way.

Depending on whether the induced voltages are the same, it can be judged whether there is an inter-turn short circuit fault. The problem of short circuit fault between turns of the motor stator is generally solved by replacing the motor winding during motor maintenance.

What to do if the insulation breaks down between turns of the motor?

The problem of insulation breakdown between turns of the motor includes poor insulation material between turns of the motor, damage to the insulation between turns during winding and inlaying, insufficient thickness of the insulation between turns or unreasonable structure, etc., which will all cause insulation breakdown failure between turns of the motor. occurrence of phenomena.

How to test the insulation between turns of motor stator winding?

In order to ensure the normal operation of the motor, the inter-turn insulation test of the motor stator winding is necessary. Whether it is a newly put into operation or a running motor, it is necessary to conduct the inter-turn insulation test.

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Post time: Sep-19-2023