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] Generally you wouldn’t want a generator solely for the purpose of operating an air compressor, but rather one that is able to run other appliances in your workplace. Therefore going for a fixed size air co.
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