Hydra probe

Measurement of soil water content, soil temperature and electrical conductivity

Get product information here:

Enquire now

Determines soil water content, soil temperature and electrical conductivity (optional) manually and in combination with data loggers

  • Simultaneous measurement of soil water content, temperature and electrical conductivity (optional)
  • Output of all readings via the SDI-12-protocol
  • Good agreement with thermogravimetrically determined water contents of soil sample rings (data on request)
  • Stored calibrations of different soil textures (optional)
  • Use with data loggers or in manually with smartphone and additional battery (Mobile Hydra-Set)
  • Versions with analog signal or RS485 optionally available
Measuring range  
Water content: Oven dry to saturated
Temperature: -10 ... +65 °C
Electrical conductivity (optional): 0,01 ... 1,5 S/m
Output signal (Standard): SDI-12
Operating voltage: 9 ... 20 V DC
Accuracy (according to manufacturer)
Water content: ± 3 % vol.
Temperature: ± 0,1 °C
Electrical conductivity: ± 5 mS/m
Power consumption: 30 mA
Dimensions  
Length: 124 mm
Diameter: 42 mm
Rod length: 57 mm
Cable length 7,5 m;other lengths available on request
Frequently asked questions about "soil moisture"

Our experience of > 25 years with soil moisture sensors tells us so far that almost all inexpensive soil moisture sensors have serious disadvantages. These are either a lack of accuracy or a comparatively short service life. In the worst case, both come together. We have deliberately kept our range of sensors for water content and water tension very small because, in addition to high accuracy and long service life, which we have checked ourselves, we place more value on continuity and expertise than on erratic reactions to movements in the market. Nevertheless, we are in some continuous development process with the constant improvement of our self-manufactured sensors.

Other people would call the statement of our competitor "alternative facts" ;-)

We have been demonstrably manufacturing sensors with the full measuring range pF 0-7 since 2008 until today (> 6,000 units), among our long-standing customers are many well-known institutions.
Please feel free to ask for references.