Although it is state of the art to equip hydraulic and lubrication systems with appropriate professional filters in order to ensure certain cleanliness within the fluid, it is astonishing that not many efforts are made to ensure the maximum use of dirt holding capacity of employed filter elements.

Professional tank top return line filters still appear just with gauges with red/ green professional scales (some of them with pull pointers). In-line filters are normally equipped with electrical clogging professional indicators, but most of them have just one switch point.

Advanced filter suppliers offer indeed indicators with two alarms; some of them are even equipped with cold start suppression and /or cold start check function. Unfortunately, these units are mostly specials and thus claim for a higher price. OEMs try to avoid high price because they have to keep their competitive position vis-à-vis their rivals.

The newly launched VSA 24 series has been developed with the aim to make use of as much dirt holding capacity as possible of a given filter element; therefore, it enables the exchange intervals predictable and can be planned. Consequently it minimises the cost for part investments. In addition, another major target was to eliminate the viscosity-induced alarm and false alarms under cold start conditions.