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] Disassemble the air compressor cylinder head. Refer to Procedure 012-106. Use a coupling puller, Part Number 3376663, or equivalent, to remove the spline coupling hub. Remove the front thrust bearing. Remove the three flange head capscrews. Remove the three captive washer capscrews.
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