Decagon EC-5 Soil Moisture Sensor

Low Cost Individual Sensors for Large Sensor Networks

The EC-5 delivers research-grade accuracy at a price that makes large sensor networks economically practical. You can adequately characterize your site with sensors at multiple depths and locations, even if you're on a tight budget.

Engineered for Accuracy

The EC-5 determines volumetric water content (VWC ) by measuring the dielectric constant of the media using capacitance/frequency domain technology. The sensor uses a 70 MHz frequency,  which minimizes salinity and textural effects, making the EC-5 accurate in almost any soil or soil-less media. Factory calibrations are included for mineral soils, potting soils, rockwool and perlite.

Easy Installation

The EC5's small size makes it easy to install--handy in field installations and good for nursery pots. The EC-5's robust design makes it easy to push directly into undisturbed soil to ensure good accuracy.

Reasons to pick the EC-5:

  • If volumetric water content is the only measurement you need.
  • If you have a tight budget
  • If you just want a simple, all-purpose sensor with excellent accuracy.
  • If you are interested in a small volume of influence (eg., field spatial variability, lab column studies or greenhouse research).

Integrate with CSI Data Loggers

The EC-5's analogue signal means no-hassle integration with systems run by other data loggers (like CSI).

Accuracy Mineral Soil:
±3% VWC, most mineral soils, up to 8 dS/m
±1-2% VWC with soil specific calibration
Rockwool: ±3% VWC, 0.5 to 8 dS/m
Potting Soil: ±3% VWC, 3 to 14 dS/m
Resolution 0.1% VWC (mineral soil)
0.25% VWC (rockwool)
Range Calibration dependant; up to 0-100% VWC  with polynomial equation
Dimensions 8.9 x 1.8 x 0.7 cm
Cable Length
5 m, custom cable lengths available upon request
Measurement Time
10 ms
2.5VDC - 3.6VDC @ 10mA
Output: 10-40% of excitation voltage (250-1000mV at
2500mV excitation)
Voltage, correlated linearly (soil) or polynomially (growing media) with VWC
-40°C to +50°C
Connector Types
3.5 mm stereo jack plug or stripped and tinned lead wires (3)
Datalogger Compatibility
(not exclusive)
Decagon: Em50, Em50G, ProCheck, Em5b
Campbell Scientific: CR10X, 21X, 23X, CR1000, CR3000, etc.
Other: Any data acquisition system capable of switched 2.5 to 3.6 V excitation and single ended voltage measurement at 12 bit or better resolution.
One year, parts and labour

Non UK/Ireland Customers

Non UK/Ireland Customers, please contact Decagon Devices at:

EC5 Volume EC-5

Click here for the Soil Sensors Comparison Page.

Soil Sensors Quick Start Guide
Size: 1.5 MB (1,533,464 bytes)

Environmental Catalogue
Size: 2.5 MB (2,581,813 bytes)

Quotation Request

Email us to request a quotation for the Decagon EC-5 Soil Moisture Sensor