GroPoint™ Lite
Accurate and Reliable Analog or Digital Soil Moisture/Temperature Sensor
Powered by TDT⁵
Soil moisture sensor retrieves measurements by averaging the volumetric water content
Digitally measures soil temperature
Flexible interface options (SDI-12, RS-485 and 4-20mA) simplify integration into a broad range of applications, ancillary equipment and data loggers.
Based on ourunique TDT5 technology.
Comes with 5m (16.4') durable cable (4-pin IP68-rated M12 connector optional).
Factory-calibrated for most agricultural soils, but can be custom calibrated before shipping—request when ordering.
Low power consumption—suitable for remote applications.
SDI-12/RS-485 version of the soil moisture sensor can be custom calibrated by the customer—see the detailed procedure in theuser manual.
GroPoint™ Lite
The GroPoint™ Lite is robust, reliable and highly accurate, providing cost-effective soil moisture and soil temperature measurements. The sleek, lightweight design installs quickly with minimal soil disruption.
When installed vertically, the soil moisture sensor averages the volumetric water content over a soil layer of about 6 inches (15 cm). When installed horizontally, the sensor can be used to measure soil moisture at a specific depth.
GroPoint Lite can be deployed in irrigation-sensitive zones, such as around the root zone, to enable an irrigation monitoring system and increase water-use efficiency.
- Specifications
- FAQs
- Downloads
Analog Version
| Moisture | |
|---|---|
| Measurement range | 0% to 100% of VMC |
| Accuracy | ±2.0% * |
| Precision | < 0.2% |
| Electrical | |
| Interface | 0-5 mA, 4-20 mA |
| Connection | Bare wire (Optional EN3 3-pin IP66/IP68 rated environmental connector) |
| Warm-up time on power up | |
| Input voltage | 6 to 14 VDC max. 18 VDC |
| Current consumption |
0-5 mA: 18 mA (nominal), 25 mA (max) 4-20 mA: 30 mA (nominal), 50 mA (max) |
| Environmental | |
| Operating temperature | -20°C to 70°C (-4°F to 158°F) |
| Storage temperature | -40°C to 85°C (-40°F to 185°F)Physical |
| Physical | |
| Dimensions | 19.6 cm x 2.0 cm x 0.56 cm (7.7” x 0.8” x 0.2”) |
| Weight | 272 g (0.6 lb.) |
| Cable weight | 38 g per m (0.42 oz. per foot) |
| Standard cable | 5 m (16.3 ft.)3xAWG22 dual-shielded, twisted pair, rated for direct burial |
| Warranty | 1-year limited parts and labour |
Digital Version
| Moisture | |
|---|---|
| Measurement range | 0% to 100% of VMC |
| Accuracy | ±2.0% * |
| Precision | < 0.2% |
| Temperature | |
| Measurement range | -20°C to +70°C (-4°F to 158°F) |
| Accuracy | ±0.5 °C |
| Electrical | |
| Interface | SDI-12, RS-485 |
| Connection | Bare wire (Optional EN3 4-pin IP66/IP68 rated environmental connector) |
| Warm-up time on power up | |
| Input voltage | 6 to 14 VDC max. 18 VDC |
| Current consumption | Quiescent: Active: 15-35 mA |
| Environmental | |
| Operating temperature | -20°C to 70°C (-4°F to 158°F) |
| Storage temperature | -40°C to 85°C (-40°F to 185°F)Physical |
| Physical | |
| Dimensions | 19.6 cm x 2.0 cm x 0.56 cm (7.7” x 0.8” x 0.2”) |
| Weight | 272 g (0.6 lb.) |
| Cable weight | 38 g per m (0.42 oz. per foot) |
| Standard cable | 5 m (16.3 ft.)4xAWG22 dual-shielded, twisted pair, rated for direct burial |
| Warranty | 1-year limited parts and labour |
* 8% to 42% VMC, in controlled laboratory conditions; factory calibrated for most agricultural soils. In field applications, accuracy may slightly decrease due to the inevitable heterogeneity of soil texture, soil compaction, moisture and fluctuation in soil temperature. The accuracy may also decrease in difficult soil conditions (higher clay and salinity content). In normal conditions, GroPoint soil sensors will maintain their accuracy from permanent wilting through field capacity in sandy loam through clay soils with less than 60% clay particles. Under moderately saline conditions, GroPoint soil sensors will maintain their accuracy up to 6 ds/m.
SDI-12
General
Are GroPoint Lite soil sensors compatible with all data loggers?
GroPoint Lite will work with virtually any data logger. Just ensure your data logger will handle the output of your
GroPoint Lite sensor whether it's SDI-12, RS-485, 0-5mA or 4-20ma. If you are looking for a datalogger, check out
GP-BTDL Bluetooth SDI-12 Data Logger
Can a GroPoint Lite soil sensor be used as a portable solution?
No, GroPoint soil moisture sensors are meant to be used on a permanent or semi-permanent basis. There should be minimal
disturbance of the surrounding soil for proper accuracy.
What is the area of influence, or measurement volume, for the sensor?
The GroPoint Lite measure the average volumetric water content along its active length about 15 cm (6″), which is
3 cm (1.25″) from the top and 2.5 cm (1″) from the bottom of the sensor, whether the sensor is installed vertically
or horizontally. Under most conditions, the sensor’s active range extends about 10 cm (4″) out from the side of the
sensor, and 2.5 cm (1″) from the tip.
I’m not in BC or Canada. Can I buy and obtain support for GroPoint products locally?
GroPoint has dealers in several international locations. You can find your local dealer on the [Dealers page][1].
GroPoint soil probes and data loggers are also sold online and we offer several self-help support resources, as well
as unlimited support via phone, email and online chat.
What measurement frequency do GroPoint soil moisture sensors operate at?
The GroPoint Lite family of sensors send TDT pulses with sub nanosecond rise times, around 500ps, so the frequency
bandwidth exceeds 1-2 GHz.
What does my sensor's ID string mean?
013RIOTTECHGPLPTS036SN612345
allccccccccmmmmmmvvvxxxxxxxx
Where:
a = sensor address (0)
ll = SDI-12 compatibility (13 for V1.3)
cccccccc = company name (RIOTTECH)
mmmmmm = sensor model number (GPLPTS)
vvv = sensor version (036)
xxxxxxxx = serial number (SN612345)
Communication & Configuration
What power-on delay time is needed for GroPoint SDI-12 sensors?
GroPoint Lite sensors need a minimum power-on delay of 350 ms before they will respond to a command.
Can you power GroPoint Lite SDI-12 sensors with a continuous 12VDC?
Yes, there is no problem continuously powering the sensors with 12V.
Does temperature come standard with the GroPoint Lite SDI-12 sensors?
Yes, the standard configuration for GroPoint Lite is with temperature sensing capabilities.
Sensor Readings
Can damage to the housing affect my moisture readings?
Minor cosmetic damage to the polycarbonate housing will not impact soil moisture or temperature readings. However,
significant damage, such as cracks or gouges, can interfere with moisture measurements. This is because larger damage
reduces the material between the soil and sensing element, and can allow water to infiltrate between the housing and
the epoxy encapsulating the sensor. For this reason, proper installation and extraction methods are essential to
prevent housing damage.
Calibration & Accuracy
Can you explain your calibration process for the GroPoint Lites?
Our calibration process is extensive, involving multiple reference solutions with different dielectric constants in
6 inch diameter columns. Each segment is individually calibrated to match a reference % moisture content.
Troubleshooting
Why are my sensor readings not as expected?
Unexpected sensor readings can result from several factors including soil disturbance, calibration mismatch,
obstructions in the measuring field, and improper installation.
4-20mA
How does the output current relate to soil moisture readings?
The GroPoint Lite 4-20mA Analog sensor outputs 4-20mA where 4mA represents 0% volumetric moisture content (VMC) and
20mA represents 50%VMC.
Installation
How do I properly install my GroPoint Lite sensor?
The GroPoint Lite sensors should be installed vertically into the ground. Avoid digging a hole if possible to minimize
soil disturbances, the design of the sensor body allows you to easily push the sensor into the ground.
Downloads
Datasheets/ Manuals
GROPOINT LITE USER MANUALGROPOINT LITE 4-20 MA QUICKSTART GUIDE
GROPOINT LITE SD-12 QUICKSTART GUIDE
GROPOINT LITE MODBUS QUICKSTART GUIDE
GROPOINT LITE DATASHEET
GROPOINT LITE MODBUS GUIDE
GroPoint Product Catalog
GROPOINT PRODUCT CATALOGSubmit a General Inquiry
Videos
GroPoint Tutorials: Data Logger Setup
Step-by-Step Guide: Set Up the Data Logger and Connect a Sensor
GroPoint Tutorials: Multiple Sensor Setup with Data Logger Kit
Step-by-Step Guide: Set Up the Data Logger and Connect a Sensor
GroPoint Tutorials: Display Unit Setup
Step-by-Step Guide: Set Up the Data Logger and Connect a Sensor
GroPoint's patented technique for soil moisture measurement
Our proprietary TDT5 technology delivers an exceptional price:performance ratio, with performance as good (in most cases better) as soil sensors costing much more.