DEWAG make conductivity level controller utilises the electrical current conducting property of the medium whose level is to be detected. Normally two electrodes are installed in a container/tank. One electrode is set at the bottom of the tank and is called a REFERENCE electrode. The other electrode is set at the point where the level is to be detected. When the material touches this electrode, an electrical current flows between these electrodes . This current is sensed and an electronic circuit actuates an electro magnetic relay, which controls the external control devices. This type of level control gives only ON / OFF output. It is possible to have level indication at more than one point.
RS-02 Series Level Controller employs three electrodes to indicate levels at two points, viz. REFERENCE ELECTRODE, LOW LEVEL ELECTRODE, and HIGH LEVEL ELECTRODE. It consists of two parts viz. Sensor Unit and Control Unit.