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] Displacement (m³/min): It refers to the volume of air discharged by the compressor per unit of time, also known as flow rate or volumetric flow rate. Discharge pressure (MPa): It indicates the pressure of the air at the compressor’s outlet, usually measured in megapascals (MPa).
[pdf] Heat generated during compression can cause air expansion before intake is completed. Poor cooling performance—whether due to inefficient oil cooling or water cooling —raises internal temperatures and reduces overall intake volume. Air displacement is directly proportional to rotor speed.
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