Check the isolation of the motor windings. Should be in the mage-ohms (you need an isolation tester / high voltage ohm meter for this). Check the voltage when the compressor is running. If the voltage drop significantly when the compressor starts/runs, you have a bad connection somewhere.
[pdf] There is dirt stuck in the wind flap or other rotating parts 1. Send the minor repair station in time to remove or replace the necessary parts. 3. If you use the air duct to refuel, do not add too much fuel at a time, but you must work hard.
[pdf] Traditional fixed-speed compressors run at a constant speed, regardless of the actual air demand. This means they often consume more energy than necessary, especially when the demand is low. VSD technology, on the other hand, allows the compressor to adjust its speed according to the air demand.
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