How To Avoid Burning Out The Vacuum Pump Motor

Oct 10, 2025

What are the methods to avoid motor burnout caused by overload in high viscosity pumps? Next, I will introduce some precautions for vacuum pumps to avoid motor burnout.

1. Operating for a long time under overload conditions

When the wrong vacuum pump specific oil is used, or when the vacuum pump lacks maintenance, the vacuum pump oil inside the pump deteriorates. When the exhaust pressure of the pump is too high, it can cause the motor to overload. Without certain overload protection, the motor will be damaged over time.

2. Operate in high ambient temperatures and poor ventilation, or at altitudes above 1000 meters

Due to poor heat dissipation, the temperature rise of the motor is too high, which can damage the coils of the motor and consume the grease inside the bearings, causing bearing damage.

3. Incorrect voltage

Some pumps may be imported or produced abroad, and the rated voltage of the motor may be different from that of our factory. Excessive or insufficient voltage can damage the motor.

4. Wiring error

It should be connected to the star type. Connecting to the delta type will cause the coil voltage to increase by 1.7 times, and the winding of the motor will heat up severely. The motor will quickly burn out, so it is not allowed to change the original star type connection to the delta type at the same voltage.

 

 

When connecting what should be connected in a delta shape to a star shape, the voltage of the motor coil decreases to 1/1.7, and the torque of the motor decreases to 1/3 of the rated value. When running at full load, the speed will sharply decrease and the current will increase. If the motor is not stopped, it will overheat and burn out. Due to wiring errors, some side flow vacuum pumps were connected in a delta shape instead of a star shape. During testing, the load was very small and the pump could operate normally. However, after running for a certain period of time, the load on the pump increased due to blockage of the pump filter and other reasons, which could cause damage to the motor.

Measures to prevent vacuum pump motor from burning out

1. It is essential that all electrical work is carried out by professional electricians.
2. Check the rated voltage, frequency, etc. of the motor. Carefully check the nameplate for wiring. If it cannot be confirmed, first connect it into a star shape, start it under no load, and gradually increase the load to check the current, etc.

 

3. It is best to keep the ambient temperature of high viscosity pumps below 40 degrees Celsius and maintain good ventilation.
4. The direction of the pump should be in the direction indicated by the arrow and should not be reversed.
5. It is prohibited to reduce the diameter of the exhaust outlet connecting pipe.
6. Timely and correct maintenance and upkeep should be carried out according to the user manual of the vacuum pump.