1. When operating under load for a long time and using unsuitable mechanical pump specific oil without maintenance, the vacuum pump oil inside the pump will deteriorate. When the working pressure of the exhaust pipe of the pump is too high, it can cause motor load. If there is no corresponding overvoltage protection, it will damage the motor for a long time.
2. Operating in high working environment temperatures and poor indoor ventilation or at altitudes exceeding one kilometer is due to poor heat dissipation, resulting in excessive temperature of the motor, damage to the electromagnetic coil of the motor, loss of vegetable oil in the rolling bearing, and damage to the rolling bearing.
3. The working voltage may not be correct. Some pumps may be imported, and the rated voltage of the motor may be different from the working voltage in China. Both high and low working voltages can damage the motor.
4. If the wiring is not correct, it should be connected to a star shaped wire. If a triangle shaped wire is connected, it will increase the working voltage of the electromagnetic coil by 1.7 times, and the winding resistance of the motor will seriously heat and quickly damage the motor. Therefore, the motor must resolutely avoid changing the original star shaped wire connection to a triangle shaped wire under the same working voltage. When the motor should be connected in a triangular shape and in a star shape, the working voltage of the electromagnetic coil of the motor drops to 1/1.7, and the torque of the motor drops to 1/3 of the rated voltage. When running at full load, the speed ratio will sharply decrease, and the current flow will continue to expand. If the motor is not turned off, it will overheat and damage the motor. Some side flow mechanical pumps are connected in a triangular shape to a star shape due to incorrect wiring. During the test run, the load was not very large and the pump could operate normally. However, after running for a corresponding time, the load of the pump continued to expand due to reasons such as clogging of the pump filtration system, which could cause damage to the motor.
5. Failure to use appropriate electrical product protection devices and high-quality electrical product hydraulic control systems. It is because some customers only use simple wiring to immediately let the mechanical pump run without installing suitable overvoltage protection, phase failure maintenance and other facilities and equipment when using the mechanical pump, resulting in damage to the motor due to various abnormal situations. There are also some consumers who need to start and close the mechanical pump from time to time in their work situation, and even frequently open and close it for one minute. Once the contact point of the AC contactor is poor, it can cause phase failure and damage. It is recommended to choose a shut-off valve for opening and closing the pump to control the continuity of the vacuum pipeline.