GroPoint™ Lite

Single-Depth Soil Moisture Sensor
Scientific-grade soil moisture measurements with fast installation and exceptional accuracy.

GroPoint™ Lite is a rugged, scientific-grade soil moisture sensor designed to measure volumetric water content and soil temperature at a single depth. Using patented TDT5 technology, it delivers highly accurate, repeatable measurements while remaining simple to install, durable, and cost-effective for agricultural, environmental, and research applications.

Key Features

  • Measures volumetric water content and soil temperature at a single depth with scientific-grade accuracy.
  • Patented TDT5 technology provides excellent long-term stability and repeatability.
  • Fast, simple installation with minimal soil disturbance.
  • Ideal for agriculture, environmental monitoring, research, turf management, and irrigation scheduling.
  • Fully sealed, rugged construction designed for long-term outdoor deployments.
  • SDI-12 digital output for easy integration with data loggers and monitoring systems.
  • Low power consumption makes it ideal for remote and battery-powered installations.
  • Excellent resistance to soil salinity and environmental variation for reliable field measurements.
  • Scientifically validated technology trusted by universities, researchers, growers, and environmental professionals worldwide.
  • 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.

4-20mA sense circuit

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.

Products Soil Sensors GroPoint Lite

Submit 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

TDT5 soil moisture 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.