1. Phase loss operation. At this time, the noise of the motor is very loud and it generates severe heat, which is also the fatal killer of three-phase asynchronous motors. It usually burns out after running for more than ten minutes. If the entire power supply system is out of phase, it is very likely to cause damage to multiple motors. The solution for a single motor is to install an electronic phase loss protector (which is essential for important motors). Also, if one phase of the fuse in the three-phase circuit is blown, it can also be a cause of phase loss.

2. The motor is damp. Insulation reduction caused by water ingress or moisture is also a common cause of damage, and daily protection measures should be taken. Pay attention to and regularly test insulation. Especially for motors driven by frequency converters, be extra careful with this, otherwise it may damage both the frequency converter and the motor.

3. Overload: If the protection function is normal (by installing a suitable thermal relay), it generally will not occur. However, it should be noted that thermal relays cannot be verified, and the protection values are not very accurate. The selection is not appropriate, and the automatic reset is manually set. Therefore, when protection is needed, it often does not work, and after multiple protections, the real cause may not be found and the protection value may be artificially increased. To render the protection ineffective.

4. Internal reasons of the motor include bearing damage, resulting in end cover wear, spindle wear, rotor sweeping, and damage and burning of the wire package.

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

6. Other: There are also less common reasons, such as low or high voltage, vibration causing loose terminals and phase to phase short circuits, insect and rodent hazards, and motor rated voltage not matching the actual voltage. Various faults in the pressure reducing starting circuit result in non conversion, prolonged low voltage operation of the motor, and so on.

The above content is compiled based on the problems encountered during the actual operation of Anhui Wannan Electric Machinery, for reference only. If there are any problems, please communicate and correct them in a timely manner.