CMS/User Guide - Filterteknik

6 Water SensorCMS-W models measure water content using a capacitive RH (relativehumidity) sensor. The result is expressed as percentage saturation.100% RH corresponds to the point at which free water existsin the fluid, i.e. the fluid is no longer able to hold the water in adissolved solution. This is also normally the point at which damageoccurs in a hydraulic system, so is an ideal measurement scale thatis independent of the fluid characteristics.The water saturation point (100% RH) is temperature dependent, sothe temperature is measured at the same time. 6 This enables resultsto be compared meaningfully.The water sensor output is affected by pressure, so the accuracy willbe proportionally degraded above 100 bar operating pressure.6 The temperature measured is that of the fluid passing through the unit. Note thismay differ from that of the hydraulic system, depending on flow rate, pipe lengthand ambient temperature. It is not intended to be an accurate indication of systemtemperature, but to provide a reference for the RH measurement. Neverthelessexperience has shown the temperature measured is within a few degrees of thatof the hydraulic system, in most applications.20 Water Sensor