GS3 Ruggedized Soil Moisture, Temperature, & Electrical Conductivity Sensor

Measurements: Electrical Conductivity (EC), Soil Moisture, Temperature

Applications: Fertigation Management, Greenhouse Management

GS3 Ruggedized Soil Moisture, Temperature and EC

The GS3 soil moisture, temperature, and EC sensor is built with an epoxy body and stainless steel needles. The internal circuitry is the same cutting edge design that you'll find in other Decagon soil moisture sensors, but the form factor has been optimized for use in soilless substrates or harsh environments, giving it a wider range of EC measurement and an increased temperature range. Not only do the steel needles improve sensor contact, but they also improve the sensor's ability to measure EC in porous substrates such as peat or perlite. 

 

Accuracy at a Fraction of the Cost

The GS3 measures water content, temperature, and EC independently. Its 70 MHz frequency minimizes salinity and textural effects, making it accurate in most soil or soilless media. Stainless steel needles have an extended surface area to optimize EC measurements, while minimizing substrate disturbance during insertion. Temperature is measured with an onboard thermistor, and electrical conductivity is measured using a stainless steel electrode array.

 

Understand Your Measurements

When used with our DataTrac 3 software, your GS3 data can be used to determine plant available water, growing degree days, and pore water electrical conductivity.

 

Easy Integration

Each GS3 comes standard with both serial and SDI-12 communication options, meaning easy integration with systems manufactured by other companies.

 

Advantages of the GS3

  • Measure VWC, EC, and temperature in soilless substrates or harsh environments
  • Manage 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 a generic calibration: ± 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): ± 5% from 0 to 5 dS/m, ± 10% from 5-10 dS/m, 10-23 dS/m custom calibration required

Temperature: ± 1°C

Note: Temperature measurement may not be accurate if sensor is not fully immersed in the medium of interest, due to excessively long equilibration time. 

RESOLUTION

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

VWC: 0.002 m3/m3 (0.2% VWC) from 0 to 40% VWC, 0.001 m3/m3 (0.1% VWC) > 40% VWC

EC: 0.001 dS/m from 0 to 23 dS/m

Temperature: 0.1°C

RANGE

εa: 1 (air) to 80 (water)

EC: 0 - 25 dS/m (bulk)

Temperature: -40 to 60°C*

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

MEASUREMENT SPEED 150 ms (milliseconds)
SENSOR TYPE

VWC: Frequency domain

EC: Two probe design

Temperature: Thermistor

OUTPUT Serial TTL, 3.6 Volt Levels or SDI-12
OPERATING ENVIRONMENT -40°C to 60°C
POWER 3.6 - 15 VDC, 0.3 mA quiescent, 25 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 9.3 cm x 2.4 cm x 6.5 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