The SWS Surface Wetness Sensor is a low-power electronic device for meauring surface moisture. It works by detecting the change in resistance across exposed carbon electrodes when they get wet. When used with a Delta-T logger such as the DL2e, the output is 0 Volts when dry, and greater than 1 Volts when wet.
Power requirement : 7-18Volts at 5mA
Active area : 150mm
Cable : 2metres
Includes ground spike.