Thetaprobe


The Thetaprobe soil moisture sensor measures the soil moisture volume percentage by applying the Frequency Domain technique. The Thetaprobe measures the soil moisture volume percentage by measuring the changes in the dielectric constant. The sensor consists of a sturdy, watertight synthetic housing which contains the electronics. The sensor is able to measure within a measuring range of 5 - 55 volumetric moisture content with an accuracy of 5% with standard calibration and only 2% with soil specific calibration. The sensor has an output signal of 0-1 Vdc. The sensor is supplied standard with a 5-metre cable and plug for connection to the soil moisture meter or with wire for connection to a datalogger. The measurement values are shown on the display of the soil moisture meter and can be stored in the memory (including time and sensor location). These data can be read on a PC. The meter comes with built-in conversion characteristics for mineral and organic soils. The software allows a further 5 soil specific calibrations to be introduced. If the moisture content is measured of other materials the meter will give an output signal in millivolts. If a series of soil moisture measurements is required the soil moisture sensors can be connected easily to a datalogger.