Decagon Devices GS3 Manual

2365 NE Hopkins Ct / Pullman, WA 99163 USA
APPLICATIONS
 Greenhouse substrate monitoring.
 Volumetric water content measurement.
 Soil/Substrate water balance.
 Irrigation management.
 Electrical Conductivity measurement.
 Salt management.
 Fertilizer movement.
 Soil/Substrate temperature measurement.
 Modeling processes that are affected by
temperature.
ADVANTAGES
 Digital sensor communicates three
measurements over a serial interface.
 2-probe EC measurement.
 Robust thermistor for accurate temperature
measurements.
 Low input voltage requirements.
 Low power design supports battery-operated
data loggers.
 Robust epoxy encapsulation and stainless
steel needles to resist corrosive environments.
 Supports SDI-12 or DDI-Serial 1-wire serial
communications protocols.
 Modern design optimized for low-cost sensing.
MEASUREMENT SPECIFICATIONS
Volumetric Water Content
Accuracy ±1 ε (unitless) from 1 – 40 ε
a
±15% from 40 – 80 ε
Generic calibration equation:
± 0.03 m
Medium Specific Calibration:
± 0.02 m
Resolution 0.1 ε
a
<0.75 ε
0.2% VWC from 0% – 40% VWC
0.1% VWC from 40% – 100% VWC
Range
a
a
/m (± 3% VWC)
3 3
/m (± 2% VWC)
3 3
(unitless) from 1 – 20 ε
a
from 20 – 80 ε
a a
1 ε – 80 ε
a a
For support contact us via email at
or call us at 1.509.332.5600 between 7AM to 5PM PST
GS3 Greenhouse Sensor
Volumetric Water Content, Electrical Conductivity, and Temperature
DESCRIPTION
The Decagon GS3 sensor is an accurate tool for
monitoring electrical conductivity, volumetric water
content, and temperature in soil and soilless
substrates. The GS3 determines volumetric water
content (VWC) by measuring the dielectric constant
(ε ) of the medium using capacitance / frequency-
a
domain technology. The sensor uses a 70 MHz
frequency, which minimizes textural and salinity
effects, making the GS3 accurate in most soilless
substrates. The GS3 measures temperature using
an onboard thermistor, and electrical conductivity
using a stainless steel electrode array.
For a more detailed description of how this sensor
makes measurements, refer to the User Manual.
AUDIENCE
Decagon provides the information in this integrators
guide to help
communication between these sensors and their
data acquisition equipment or field data loggers.
Customers using data loggers that support SDI-12
sensor communications should consult the user's
manual for their data logger. These sensors are fully
integrated into Decagon's system of plug-and-play
sensors, cellular-enabled data loggers, and data
analysis software.
Temperature
± 1°C
± 10% from 0 to 5 – 25 mS/cm (dS/m)
0.1°C
- 40°C to + 50°C
support@decagon.com
GS3 customers
Electrical Conductivity
± 5% from 0 to 5 mS/cm (dS/m)
user calibration required above:
25 mS/cm (dS/m)
0.001 mS/cm (dS/m)
0 – 25 dS/m
establish
1