Given a ND system that is fully charged, operational and containing the correct oil quantity:
1) Is it a safe assumption that the oil present is the system is uniformly distributed, with the volume present in each system component dependent on the size of the component and thus
2) the quantity present in (drained from) the compressor would therefore be a % of the total present within the system?
3) If the compressor oil quantity does accurately and repetitively represent a percentage of the system's total and that quantity and percentage is known, would a linear relationship exist whereby one could calculate oil quantity present in systems where oil loss is suspected or known or an oil overcharge condition exits?
Obviously, this calculation would not work in systems where there has been a catastrophic loss (hose rupture) or the compressor is inoperative.