It should turn around smoothly, without any 'hickups' (be sure to completely shut down the air compressor!). 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.
[pdf] This manual describes the safety precautions, structure and functions of all systems and components, as well as the operation and maintenance methods for the KHE series rotary screw air compressors. The owner and operator shall read the manual carefully.
[pdf] Regular maintenance helps avoid these issues, reducing operational costs, energy consumption, and improving overall productivity. Daily Maintenance Inspection: Before each use, check for loose bolts, proper belt tension, and sufficient oil levels.
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