portfolio page

Soil Moisture Sensor

This Soil Moisture Sensor is designed to fulfil the needs of precision irrigation, it is built on capacitive/FDR mechanism and its accuracy is very high.

This Soil Moisture sensor is available in multiple depth options such as 15 cm, 30 cm, 45 cm, 60 cm, 75 cm and 90 cm.

Soil moisture readings can be viewed and analyzed using the mobile application and this soil moisture sensor can also be integrated with single plot or multi plot motor controller for precision irrigation scheduling.

Following are some key features of Soil Moisture Sensor Features:

1. Voltage Supply - DC 5- 12 Volt +/- 0.5 Volt

2. It support 4 AA lithium batteries as power backup with Solar Charging on top

3. Current Consumption - max 105mA or minimum

4. Output Signal Voltage Level - 3.3Volt(via USB)

5. Temperature Range - (-40 degree to 85 degree C, Industrial)

6. Measurement mechanism – Capacitive/FDR type measurement

7. Measurement Range - 0.000pF to 1000uF

8. Data Logging Capability (local) - 16 GB(Can be extended to upto 32GB)

9. Data Logging Maximum Frequency - 4 MHz

10. Serial Data Output baudrate, by default @9600 bps(configurable upto 115200)

11. Data should be read throughout the electrodes

12. Rugged and robust design

13. It has inbuilt GSM/GPRS Engine with universal SIM support(Preferably BSNL)

14. It can send data to any IoT Cloud via its compatible POST api Web Service

15. Data should be compatible with most of the commercial grade Pump Motor Controllers via Serial/I2C/SPI/CAN/PWM Communication

16. Power Indication LED(3 mm)

17. Data Logging troubleshoot LED(3 mm)

18. Easy Firmware version upgrade via USB/Cloud

19. Should support on field/Cloud Calibration

20. Electrode Material - Glass Epoxy Cu plate or SS316 material

21. Electronics Enclosure Body – ABS/Polycarbonate Plastic

22. Sensor Electrode Dimension – comes in various length maximum up to 90 cm

Measuring soil moisture is important for agricultural applications to help farmers manage their irrigation systems more efficiently. Knowing the exact soil moisture conditions on their fields, not only are farmers able to generally use less water to grow a crop, they are also able to increase yields and the quality of the crop by improved management of soil moisture during critical plant growth stages. The soil moisture sensor is one kind of sensor used to measure volumetric content of water within the soil. In this we measure dielectric constant of a certain volume element around the sensor is obtained by measuring the operating frequency of an oscillating circuit. The sensor data can either be viewed on farmers mobile phone or linked to any smart pump controller.  

·        It measures soil moisture with FDR (Frequency Domain Reflectometry) technology.

·        This Module determines the amount of soil moisture by measuring the frequency between two metallic probes that is inserted into the soil to be monitored.

·        Sensors can be connected to a two-wire path and provide automatic or user-requested measurements so the controller can make smart irrigation decisions specific to the landscape the sensor is installed in.


Featuresof Soil moisture sensor

·        Easyto use with Microcontrollers or with normal Digital/Analog IC

·        Supportup to clock speed of 16MHz.

·        Bootup time is less than 5sec.

·        OperatingVoltage: 5V to 12V DC

·        OperatingCurrent: <10mA for sensor

·        Probesmade from SS316 which is corrosion free.

·        High resolutionwhile moisture measuring method being implemented.

·        Accuratelymeasures soil moisture using patented modified FDR technology.

·        OLED graphicsdisplay for soil moisture readings.

·        Soilmoisture readings are very close to the actual volumetric soil moisturecontent.

·        Hastrue two-way communication using a 9-byte packet for commands and replies.

·        Sensorcomes with different probe length of 30cm, 60cm and 90cm.

·        4G,3G, 2G universal SIM type support including BSNL.

·        CommunicationSystem- LTE/DC-/HSPA+/UMTS/ EDGE/ GSM.

·        SpeedFDD LTE Cat4: 150/50 Mbps @20 M BW HSPA+ 42/5.76, 21/5.76 Mbps HSPA: 14/5.76, 7.2/5.76Mbps.

·        ExternalAntenna Interface-TS-5 of 2dB and 50ohm impedance.

·        ReceiveDiversity- All the LTE and 3G bands.

·        Non-linearity±3%(10%-120% rated input current)

·        Frequency50 Hz to 150KHz.

·        IP-65protection for enclosure.

·        Soilmoisture content display on OLED device.

·        Directandroid mobile application connectivity support.

·        Externalaviation connector for calibration and firmware upgrade.

·        Inbuilthigh-capacity lithium-ion battery with smart charger.


Operation of soil moisture sensor



  1. Place     any SIM card with activated internet pack in to the SIM card slot     provided in the soil moisture sensor.
  2. Make sure     the external antenna should be put in vertical direction and as far as     possible from any sharp metallic object and the power source/control     panel.
  3. Connect the     power 3.5mm connector in the sensor.
  4. Insert the measuring     inside the soil up to the marked position.
  5. Please make sure all the connections are     intact.
  6. Switch on the power switch of the sensor.
  7. Wait for some time to get GPRS     network established.
  8. The soil moisture will be displayed     on OLED device.
  9. The data can be viewed at this point     via its registered mobile application.





·        Thiscan be used in an automatic plant watering system or to signal an alert of sometype when a plant needs watering.

·        Thesesensors are calibrated once for all soil types and conditions and are unaffected by salty soil conditions or soils with ahigh pH.

·        Portableand easily installable.

·        Notaffected by salts or fertilizers.

·        Moisturereadings are consistent in salty conditions.

·        ItsIP65 grade enclosure is suitable for harsh environmental condition.

·        Soil moisturesensor is designed with quality components promises longer life cycle of theimplement.

·        Sensoris made up of corrosion free SS316 material which gives longer life.

·        Itensures faster operation and completes function in less time reducing powerconsumption.

·        It canbe viewed using this mechanism from any remote places hence no distancerestriction.

·         All components of soil moisture sensor consumevery less power hence contribute towards the power saving.

·        Shockresistant.

·        Powersurge resistant.

·        Small,cost effective and easily available.

Installation Instructions

Ø  Install the soil moisture sensor in a location representative ofthe zones that the sensor is controlling.

Ø  Bury the soil moisture sensor so there are no air pockets or rocksin contact with the sensor.

Ø  Bury the soil moisture sensor in an area of average water distributionbetween two sprinkler heads and place it on the centerline between sprinklers.

Ø  Only trained technician should be allowed for the installation of soilmoisture sensor.

Ø  Requires all connections to be installed according to manufacturer’sinstructions.

Ø  Connect the soil moisture sensor to the two-wire permanufacturer’s specifications.

Ø  Don’t interfere the wiring of sensor during its operation.

Ø  Maintain the distance between the electrode from bottom to top uniformlyacross its length.

Ø  Use foamed and bubbled packaging box to transport this device toavoid any physical damage.

Ø  The farmer and end users should be properly trained for androidapplication and soil moisture sensor operation.

Ø  Before making installation changes make sure the power supply iscompletely disconnected/removed.


Safety measures


General safety suggestions include:

·          Read and follow the manufacturer’sinstructions for operation.

·          Don’t remove or modify safetyfeatures.

·          Ensure that everyone workingon the farm is thoroughly familiar with operating procedures and safetyrequirements of soil moisture sensor use.

·          Please make sure the soilmoisture sensor switch is off before making any connection.

·          Use of insulating glovesshould be recommended for installation.

·          Never place any electricalmeasuring instrument near the soil moisture sensor.

·          Fit falling object protectivestructures (FOPS) for soil moisture sensor.

·          Keep a well-stocked,up-to-date first aid kit in an accessible area.

·          Repair and replacement of componentshould be done with appropriate ratings and by authorized person.

·          Always use insulated tools forinstallation and replacement of any parts.

·          Do not place any heat sourcenearby soil moisture sensor.


Team Member


Positive Feedback


Projects done


Lines of code