Vortex compression is a kind of volumetric compressor, which makes use of the meshing of the scroll rotator and the scroll stator to form a number of compression chambers. With the translational rotation of the vortex rotator, the volume of each compression chamber changes constantly, so that the gas can be inhaled and compressed. Today, we bring you the motor winding burned down for the analysis of common faults of scroll compressor.

 

The burnout of motor windings is related to the protection of electrical design or the improper operation and use of water chillers.

 

1. Abnormal load: the compressor built-in thermal protector frequently acts, which may cause its contacts to adhere and use the protector to lose its function, thereby burning the motor. Lubrication failure and friction resistance increase are the main causes of abnormal load. In order to solve the problem of lubrication failure, we should mainly start from the following aspects: preventing the return of liquid, preventing the overheating of lubricating oil (high exhaust temperature), and solving the problem of oil return or oil shortage in the system.

 

2. If there is no overload protection or over-current protection in the electrical design, the following dangers may arise: if the compressor current is large, the motor winding will continue to work at a higher temperature, which is not enough to make the built-in thermal protector operate. In this case, the coil insulation layer may be damaged and the motor will be short-circuit burned. Increasing external overload protection is an effective means to prevent motor burnout, such as thermal relay protection. The set value of the hot breaker can be disconnected when the rated current of the compressor is not more than 140%. In addition, it is also very important that the power supply wire of the chiller goes through the air switch.

 

3. Frequent start-up of the motor will make the corner of the contactor with poor quality prone to adhesion. In this way, relying on contactor to disconnect all protection control of compressor power supply circuit (high and low pressure protection, exhaust temperature protection, water flow protection, etc.) will all fail, and the compressor of water cooler will be in unprotected state, resulting in motor burnout. Therefore, the contactor should be selected correctly.

 

4. Insufficient cooling is also one of the causes of burnout of compressor motor. Fully enclosed scroll compressor is usually cooled by refrigerant, and a large amount of leakage of refrigerant will cause insufficient compression cooling. Of course, a large amount of leakage of refrigerant will generally cause low-pressure protection or thermal protection, but if the low-pressure protection and thermal protection of water chillers fail, it will cause the burning of compressors.