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] To use an air compressor, place it on a flat surface, connect the hose and power tool, set the pressure based on your tool’s needs, and wear safety gear like goggles and ear protection. Remember to check oil (if needed), drain moisture from the tank after use, and store the compressor properly.
[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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