Checkout Current Transformers (CTs) and check resistance across each one while it is disconnected. All resistances should be within 10% of one another. Also do a diode test on the CT inputs on each compressor module. (The diode test is described in RTAA-SVB10B-EN.)
[pdf] When matching motor characteristics to compressor requirements, one should consider factors such as voltage, phase, and duty cycle. The motor’s rated horsepower should ideally be closely matched to the compressor’s demands to ensure optimal performance.
[pdf] Rotary screw electric air compressors provide a continuous supply of air. They have two internal screws that rotate in opposite directions, trapping and compressing air. The constant movement differs from piston air compressors that start and stop to meet air flow needs.
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