Setting an alarm level for water in oil is very important for machine reliability. Establishment of levels, combined with testing at proper intervals, will allow the end user to act quickly if a sudden increment of water is detected.
Best practice is to maintain water levels at or below half of the saturation level of the oil at its operating temperature. For example, if the saturation level is 1000 ppm at 50°C (used °F previously, now switched to ℃), the caution level should be set at 500 ppm, with the critical level at 1000 ppm.
Following Table shows the levels of dissolved, emulsified and free water in oil that will be expected for different types of oils. It is important to know the oil base oil type, additive package, operating temperature and pressure before establishing the alarm level.
