5TM: Soil Moisture and Temperature Sensor

The 5TM determines volumetric water content (VWC) by measuring the dielectric constant of the soil (or other media) using capacitance/frequency domain technology. Signal filtering minimizes salinity and textural effects, making the 5TM accurate in most soils and soilless media. Factory calibrations are included for mineral soils, potting soils, rockwool, and perlite. The 5TM's small size makes it easy to install in the field and the greenhouse. This robust sensor can be pushed directly into undisturbed soil to ensure good accuracy. Get straight to the data with an Em50-series data logger. Just install the 5TM, plug it into the Em50, set the clock and measurement intervals, and start logging data. No programming required. The 5TM comes standard with both serial and SDI-12 communication options, meaning easy integration with systems manufactured by other companies.

  • Key Features
  • Applications
  • Specifications
  • Downloads
  • Video
  • Temperature Integrated with Soil Moisture
  • Engineered for Accuracy
  • Easy Installation
  • Plug and Read
  • Greenhouse Management
  • Microbial Ecology
  • Soil Respiration
  • Watershed Characterization
Accuracy Apparent dielectric permittivity (E a): ± E a (unitless) from 1-40 (soil range), ±15% from 40-80
VWC: Using Topp equation: ±0.03m3/m3 (±3% VWC) typical in mineral soils that have solution electrical conductivity <10dS/m
Using medium specific calibration, ±0.01 - 0.02m3/m3 (±1-2% VWC) in any porous medium
Temperature: ±1°C
Resolution Ea: 0.1Ea (unitless) from 1-20, <0.75Ea (unitless) from 20-80
VWC: 0.0008m3/m3 (0.08% VWC) from 0to 50% VWC 0.25% VWC (rockwool)
Temprature: 0.1°C
Range Ea: 1 (air) to 80 (water)
EC: 0-23 dS/m (bulk)
Temperature: -40-50°C
Dimensions 10 x 3.2 x 0.7cm
Cable Length 5m, custom cable lengths available upon request
Measurement Time 150 ms
Power 3.6-15 VDC, 0.3mA quiescent, 10mA during 150ms measurement
Output RS232 or SDI-12
Connector Types 3.5mm stereo jack plug or stripped and tinned lead wires (3)
Data Logger Compatibility  Decagon: Em50, Em50G, ProCheck
Campbell Scientific: CR200X - series, CR800/CR850, CR1000, CR3000, CR9000X
Other: Any data acquisition system capable of 3.6-15V excitation and serial or SDI-12 communication
Warranty One year, parts and labour