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] The Micro Oil Screw Air Compressor uses two rotors (screws) that rotate in opposite directions. As the screws turn, air is drawn in and compressed. The oil injected into the system lubricates and cools the compressor element while also sealing the gap between the screws.
[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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