Motor winding damage is generally caused by the following conditions:
1, insulation is damaged, the temperature of the motor is too high during operation, and the winding is burnt out due to the burning of the insulator.
2. The service life of the motor winding has reached the limit, and the insulator is aging, resulting in the winding burning out.
3. The motor runs under high load for a long time, which leads to accelerated aging of insulators and damage of motor windings.
4. There is a problem with the motor connection circuit, which leads to the winding burning out.
5. The motor suffers from natural disasters such as lightning strike, which leads to short circuit and burning of the winding.
Extended data:
Precautions for removing the motor:
1. Before disassembly, blow off the dust on the motor surface with compressed air and wipe it clean.
2. Choose the working place of motor disintegration and clean up the site environment.
3, familiar with the motor structure characteristics and maintenance technical requirements.
4. Prepare tools (including special tools) and equipment required for disassembly.
5, in order to further understand the defects in the operation of the motor, conditional can do an inspection test before disassembly. Therefore, put the motor into load trial operation, check the temperature, sound and vibration of each part of the motor in detail, and test the voltage, current and speed, then disconnect the load, do a no-load inspection test alone, measure the no-load current and no-load loss, and make records.
6. Cut off the power supply, remove the external wiring of the motor, and make records.
7. Choose a suitable voltage megger to test the insulation resistance of the motor. In order to compare with the insulation resistance measured in the last overhaul and judge the changing trend and insulation state of the motor, the insulation resistance measured at different temperatures should be converted into the same temperature, generally 75℃.
8. Test the absorption ratio K. When the absorption ratio is greater than 1.33, it means that the insulation of the motor is not affected with damp or the degree of damp is not serious. In order to compare with the previous data, the absorption ratio measured at any temperature should also be converted to the same temperature.
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