Try to turn the compressor by hand. It should be possible to turn it around. It should turn around smoothly, without any 'hickups' (be sure to completely shut down the air compressor!). Check the isolation of the motor windings.
[pdf] The Variable Frequency Rotary Screw Air Compressor is an energy efficient solution for industrial air compression requirements. The motor output frequency is intelligently matched to air consumption, making it more energy efficient and longer lasting than traditional air compressors.
[pdf] The JX-100APMX is a single-stage screw air compressor engineered for maximum reliability, even in critical applications. It ensures minimal oil emissions, with exhaust levels not exceeding 3 parts per million. Powered by a robust 75 HP (55 kW) motor, it achieves an impressive speed of 3000 RPM.
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