Asynchronous motor rotor coil insulation test specification:

　　1. All tests are for one minute. The so-called one minute is: the test should start with a voltage not exceeding one-third of the voltage, gradually or not more than 5% each time and step up to the full value of the test voltage, while testing the voltage When it is raised from its half value to the full value, the allowable time should not be less than 10 seconds, then all voltages should be maintained for one minute, after which it drops to 1/3 of the full value and is broken.

　　2. The test voltage should be AC, and the weekly rate is approximately 50 cycles and the actual sinusoidal waveform.

　　3. When testing a part or a phase of the coil, all untested parts of the coil must be grounded.

　　4. After the coil insulation is completed, when testing individual coils, the length of all metal leaves (copper or aluminum foil) is 10 mm longer (3000 volts and below) than the length of the core.

　　5. The motor must measure its insulation resistance before the last high voltage test. After the insulation resistance grid is placed, the withstand voltage test is performed.