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] Replace screw air compressor lubricating oil by stopping the machine, draining old oil, cleaning pipelines, adding new oil, and replacing the oil filter. Check oil level after starting.
[pdf] Before making any repairs, be sure the unit is unplugged and tank has no air. To remove the line and load cords from the pressure switch, the pressure switch cover will need to be removed. Use your Phillips head screwdriver to loosen the screw located either on the top or on the side of the cover.
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