The Charis SureSense range is designed for water-based materials foam or liquid control. The DiFoam range is used for non water-based materials such as oil, resin, solvents.

The Charis Technology Foam Sensor operates by passing a small alternating current through the foam or the liquid under test, and uses this to measure impedance. The impedance of the material being sensed is used to determine the presence of foam or liquid.

The sensor is designed with two electrodes called Sense (at the end of the sensor) and Guard (on the body of the sensor). The Sense electrode is used to sense foam while the Guard electrode is designed to prevent the build-up of any surface coating from causing false readings. The Guard electrode supplies all the leakage current leaving the Sense electrode to sense only foam and isolates the sensor from the interference caused by fouling.
This technology enables the sensor to continue working reliably even in conditions of extreme fouling.

These systems will fit any vessels from two litres to a hundred cubic metres capacity.
Sensors are available in 12 mm  or 18mm diameter.