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] 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.
[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.
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