Soil moisture sensor Thetaprobe
The Thetaprobe (ML3) soil moisture sensor (art. no.: 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 changes are converted into a millivolt signal proportional to the soil moisture content. The sensor consists of a sturdy, watertight synthetic housing which contains the electronics. The housing is fitted with 4 stainless steel measuring probes at one end that can simply be pushed into the soil (or other material). The Thetaprobe also can measure soil temperature.
Soil moisture sensor Thetaprobe
Measuring range
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.

Benefits soil moisture sensor Thetaprobe
  • Versatile instrument, measures and stores %
  • Push probe, read and store data
  • Can be extended with profile probe 4-6 levels
  • Can be extended with conductivity sensor
  • Two standard calibrations, three user curves=
  • A fair accuracy for a fair price
  • Own soil data allow direct irrigation advice
  • Special 6 port datalogger allows easy user connection of sensors

  • % can be translated to suction with pF curve
  • Calibrations in instrument or own spreadsheet

Technical Specifications
Maximum measuring depth >100 cm
Measuring accuracy ± 1 - 2%
Measuring principles FD (volumetric, permittivity derived)
Measuring range 5 - 55% + mV + mm deficit
Reading accuracy 0.1 volume%
Package size 30 x 10 x 10 cm
Volume of material needed 170 ml
Weight 300 gr

  • Geohydrological research
  • Irrigation research
  • Soil moisture measurements

click here for a Quote...!