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] Rotary screw air compressors are built to last for several years of professional quality operations. That said, all air compressors do have their limits and wish to be inspected periodically to ensure optimal performance for the duration of their lifespan. A rotary screw air compressor consists of several key internal. .
I have picked out this example of maintenance guidelines, or a checklist, provided by Eaton in their rotary screw air compressor manual!. .
If you have any questions regarding rotary screw air compressor maintenance, please leave a comment below, with a photo if applicable, so that someone can help you!
[pdf] After around 20,000 hours or four years of operation, screw air compressors usually require major maintenance, including bearing replacement. Long-term operation leads to internal bearing wear, causing loud noise and high temperatures. These signs indicate the need for an overhaul.
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