Features
The moisture in oil can be expressed in absolute or relative terms.
Water activity aw is the relative measure for moisture in oil. It represents the ratio between the actual amount of dissolved
water and the maximum possible amount of dissolved water in the oil at a certain temperature. The aw value indicates the
degree of saturation of the oil. aw = 0 indicates completely dry oil, aw = 1 indicates fully saturated oil. The water activity is
independent of the type of oil and shows how close to saturatio n is the oil at any moment in time.
Water content x is an absolute measure for the amount of water in the oil (dis solved, emulsified or separated). The water
content is usually expressed in ppm or mg water / kg oil and it is independent from the oil temperature. For asse ssing the
degree of saturation, x must be regarded together with T.
EE364 calculates x based on the measured aw and T values. The calculation is oil dependent and requires a set of oil
specific parameters. E+E offers the service of determining the oil specific parametrs, see section “Accessories” below. The
parameters can be set upon order or uploaded to EE364 using the EE-PCS Product Configuration Software (available at
www.epluse.com/configurator).
Measurement Water activity aw / Water content x