What are the common causes of motor burnout?

Update:01 Nov 2018
Summary:

1. Phase loss operation. At this time, the noise of the […]

1. Phase loss operation. At this time, the noise of the motor is very large, and it is severely heated. This is also a deadly killer of the three-phase asynchronous motor, which usually burns out after ten minutes of operation. If the entire power supply system is out of phase, it is likely to cause damage to multiple motors. The best solution for a single motor is to install an electronic phase loss protector (this must be used for important motors). There is also the fact that if the fuse in the three-phase circuit is blown by a certain phase, it is also a cause of phase loss.

2. The motor is damp. Because the insulation caused by water or moisture is reduced, it is also a common cause of damage, and daily protection should be done. Attention and periodic testing insulation. Especially for motors driven by inverters, you should be careful with this item, otherwise the inverter may be damaged.

3. Overload: If the protection function is normal (adding a suitable thermal relay), it will not happen. However, it should be noted that because the thermal relay can not be verified, and the protection value is not very accurate, the selection is not suitable, etc., and the artificial setting is automatically reset, so when protection is needed, it often does not work, and may also After many protections, the real reason was not found, and the protection value was artificially increased. To disable the protection.
4. Internal causes of the motor, due to bearing damage, end cap wear, spindle wear, rotor broom, and wire package damage are also a major cause.

5. The vacuum switches used in underground coal mines now have overcurrent protection and should be used consistently.

6. Others: There are other reasons that are not very common: if the voltage is too low or too high, the vibration causes the terminal to be loose and phase-to-phase short circuit, the pest of the pest, the rated voltage of the motor and the actual voltage do not match. Various decompression starting circuit failures cause no conversion, the motor works for a long time and low voltage, and so on.