Soil Moisture, Temperature, and Electrical Conductivity

The 5TE monitors bulk electrical conductivity (EC), in addition to volumetric water content (VWC) and soil temperature.

 

Monitor Salt Levels

The 5TE enables users to measure the EC response to salts and fertilizers in the soil. EC Measurements require good contact between the stainless steel electrodes on the sensor, and the soil. In potting soil and soilless medias, we recommend using the GS3 to maintian good soil contact and compensate for air gaps in the substrate. 

 

Engineered for Accuracy

The 5TE determines 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 5TE accurate in most soils. The 5TE measures temperature with an onboard thermistor, and electrical conductivity using a stainless steel electrode array. VWC in mineral soils is calculated using the Topp equation; other calibrations are provided on request. Temperature and electrical conductivity are factory calibrated for all soil types.

 

Easy Installation

The 5TE's small size makes it easy to install in the field and the greenhouse. This robust sensor should be pushed directly into undisturbed soil to ensure good accuracy.

 

Easy Integration

Each 5TE comes standard with serial and SDI-12 communication options, meaning easy integration with systems manufactured by other companies.

 

Advantages of the 5TE

  • Measures VWC, EC, and temperature
  • Monitoring salts
  • SDI-12 compatible

ACCURACY

Apparent Dielectric Permittivity (εa): ± 1 εa (unitless) from 1 - 40 (soil range), ± 15% from 40 - 80

Soil Volumetric Water Content (VWC): Using Topp equation: ± 0.03 m3/m3 (± 3% VWC) typical in mineral soils that have solution electrical conductivity < 10 dS/m; using medium specific calibration, ± 0.01 - 0.02 m3/m3 (± 1 - 2% VWC) in any porous medium

Electrical Conductivity (EC): ± 10% from 0 to 7 dS/m, user calibration required above 7 dS/m

Temperature: ± 1°C

RESOLUTION

εa: 0.1 εa (unitless) from 1 - 20, < 0.75 εa (unitless) from 20 - 80

VWC: 0.0008 m3/m3 (0.08% VWC) from 0 to 50% VWC

EC: 0.01 dS/m from 0 to 7 dS/m, 0.05 dS/m from 7 to 23.1 dS/m

Temperature: 0.1 °C

RANGE

εa: 1 (air) to 80 (water)

EC: 0 - 23 dS/m (bulk)

Temperature: -40 - 60°C*

*Sensors can be used at higher temperatures under some conditions.  Contact Decagon for more details.

MEASUREMENT TIME 150 ms
SENSOR TYPE

VWC: Frequency domain

EC: Two probe design

Temperature: Thermistor

OUTPUT RS232 (TTL), or SDI-12 
OPERATING ENVIRONMENT

40° to 60°C*

*Sensors can be used at higher temperatures under some conditions.  Contact Decagon for more details.

POWER REQUIREMENTS 3.6 - 15 VDC, 0.3 mA quiescent, 10 mA during 150 ms measurement
CABLE LENGTH

Sensors come standard with 5 m cable. Custom cable lengths available. Maximum cable length of 75 m. Please contact Decagon if you need longer cable lengths.

CABLE CONNECTOR TYPES

3.5 mm "stereo" plug, or stripped and tinned lead wires (3)

SENSOR DIMENSIONS

10 cm x 3.2 cm x 0.7 cm

DATA LOGGER COMPATIBILITY 
(NOT EXCLUSIVE)

Decagon Em50 Series, ProCheck, Campbell Scientific

WARRANTY

One year, parts and labor

ANALOG SENSORS  
SENSOR EC-5 10HS GS1
MEASURES volumetric water content, dielectric permittivity volumetric water content, dielectric permittivity volumetric water content, dielectric permittivity
VOLUME OF INFLUENCE 240 mL 1320 mL 1430 mL
DATA LOGGER COMPATIBILITY Em5b, Em50, Em50G, ProCheck, ECH2O Check, Campbell Scientific* Em5b, Em50, Em50G, ProCheck, ECH2O Check, Campbell Scientific* Em5b, Em50, Em50G, ProCheck, ECH2O Check, Campbell Scientific*

MEASUREMENT RANGE

0 to 100% VWC 0 to 57% VWC 0 to 57% VWC
BEST IF

VWC is all that you need.

You're establishing a large sensor network.

You want a large measurement volume.

VWC is all that you need.

You're establishing a large sensor network.

You're installing in the side wall of a trench.

You need the most rugged sensor available.

BUT NOT IF You cannot apply a regulated voltage (only applies to non-Decagon data loggers).

You are measuring in nursery pots.

You are installing in rocky soil.

You are installing sensors down bore holes.

 

DIGITAL SENSORS  
SENSOR 5TM 5TE GS3 MAS-1  
MEASURES volumetric water content, dielectric permittivity, temperature volumetric water content, dielectric permittivity, temperature, electrical conductivity volumetric water content, dielectric permittivity, temperature, electrical conductivity volumetric water content  
VOLUME OF INFLUENCE 715 mL 715 mL 160 mL 450 mL  
DATA LOGGER COMPATIBILITY Em50, Em50G, ProCheck, Campbell Scientific*, SDI-12 capable Em50, Em50G, ProCheck, SDI-12 capable Em50, Em50G, ProCheck, SDI-12 capable Any logger with 4-m20 mA input (not compatible with Decagon data loggers or ProCheck)  

MEASUREMENT RANGE

0 to 100% VWC

-40 to 60 °C

0 to 100% VWC

-40 to 60 °C

0 to 23 dS/m

0 to 100% VWC

-40 to 60 °C

0 to 25 dS/m

0 to 100% VWC

-40 to 60 °C

 

BEST IF

Measure High temperature variability.

Data must be corrected for temperature effects.

Using SDI-12.

You are managing salts in your system.

You want to use SDI-12.

You are measuring water content of soilless substrates.

You need high accuracy EC.

You are working with a PLC with a 4-20 mA input.

You need extremely long cable lengths.

 

BUT NOT IF N/A You want to monitor soiless substrates or potting soils. You are installing sensors down bore holes.

You want to use Decagon data loggers or ProCheck.

You need a low-power system.

 

Compatibility and Programming Specifications for Campbell Scientific and Other (non-Decagon) Data Loggers

Note: ECH2O sensors are “plug and read” on Decagon data loggers. You do not need to program any of this information (or ANY information) into a Decagon logger.

SENSOR CAMPBELL COMPATIBILITY OTHER LOGGERS OUTPUT VOLTAGE REQUIREMENTS
EC-5 CR10X, 21X, 23X, CR1000, CR3000, etc. 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. (Note: some people take their chances with resolution as low as 3 bits, but resolution lower than 10 bits will leave the data quite choppy). Voltage, correlated linearly (soil) or polynomially (growing media) with VWC 2.5-3.6 V
10HS CR10X, 21X, 23X, CR1000, CR3000, etc. Any data acquisition system capable of 3-15 VDC excitation and single ended voltage measurement at 12 bit or better resolution. Voltage correlated with VWC, independent of excitation 3-15 V
5TE Any logger with serial I/O (CR10X, CR850, CR1000, CR3000, etc.) Ask a Decagon representative for an integrator’s guide to interfacing the 5TE Digital ASCIII stream or SDI-12 3.6-15 V
5TM Any logger with serial I/O (CR10X, CR850, CR1000, CR3000, etc.) Ask a Decagon representative for an integrators guide to interfacing the 5TM Digital ASCII Stream or SDI-12 3.6-15 V
GS3 Any logger with serial I/O (CR10X, CR850, CR1000, CR3000, etc.) Ask a Decagon representative for an integrators guide to interfacing the GS3 Digital ASCII Stream or SDI-12 3.6-15 V
GS1 CR10X, 21X, 23X, CR1000, CR3000, etc. Any data acquisition system capable of 3-15 VDC excitation and single ended voltage measurement at 12 bit or better resolution. Voltage correlated with VWC, independent of excitation 3-15 V
MAS-1 Any logger with 4-20 mA output Any logger with 4-20 mA output 4-20 mA 12-32 VDC continuous