Sensors probes

General comments

The following sections describe the main features and the general usage for all the sensors probes included in the Plug & Sense! Smart Agriculture Xtreme model.

It is important to remark that Smart Agriculture Xtreme is only available in the Waspmote Plug & Sense! line. It is not available for the Waspmote OEM line. Besides, keep in mind that Smart Agriculture Xtreme is not compatible with the former Smart Agriculture or Smart Agriculture PRO models. In other words, the sensor probes described in this Guide are only compatible with Smart Agriculture Xtreme, because its advanced electronics allow these specific sensor integrations (some exceptions are the BME, Ultrasound or Luminosity sensors).

In order to keep this guide as short as possible, some manufacturer information has been omitted. Libelium encourages the reader to visit the manufacturer websites and to spend some time studying all the technical papers and application notes provided for each sensor. Measured parameters on the great majority of Smart Agriculture applications require a deep knowledge of the environmental parameters and, what is more, sophisticated measurement techniques to obtain the best accuracy.

Additionally, Libelium highly recommends carrying out comprehensive laboratory tests before installing the system on the field, as well as proof of concepts on the field during a reasonable period, before going to a real deployment. Thanks to these good practices, the user will have an idea of the platform behavior, which will be very close to reality. Parameters like accuracy over time or battery drain can be only measured with real tests.

Finally, always take into account a maintenance factor for each sensor probe. The environmental conditions could affect the sensor behaviour and accuracy therefore it will become mandatory periodic maintenance for each sensor probe, to watch out things like dirty on sensor probes, measure position or wire connections. The period between these maintenance actions will be different on each application. Contact our Sales department through the next link if you require more information: http://www.libelium.com/contact.

Non-contact surface temperature measurement sensor probe (Apogee SI-411)

The Non-contact surface temperature measurement sensor probe is able to measure the electromagnetic radiation that every object with a temperature above absolute zero emits, which is used to calculate the surface temperature from a distance. Thanks to this, the temperature of the object's surface is not altered in any way when measuring it.

Figure: The non-contact surface temperature measurement sensor probe (Apogee SI-411)

Specifications

• Operating environment: -45 to 80 ºC

• Operation humidity: 0 ~ 100% RH (non-condensing)

• Calibration uncertainty (-20 to 65 ºC), when target and detector temperature are within 20 ºC: 0.2 ºC

• Calibration uncertainty (-40 to 80 ºC), when target and detector temperature are different by more than 20 ºC: 0.5 ºC

• Measurement repeatability: less than 0.05 ºC

• Stability (long-term drift): less than 2% change in slope per year when germanium filter is maintained in a clean condition

• Field of view: 22º (half angle)

• Spectral range: 8 to 14 µm; atmospheric window

• Dimensions: 23 mm diameter; 60 mm length

• Mass: 190 g (with 5 m of lead wire)

• Cable length: 5 m

Measurement process

The SI-411 sensor provides a digital signal using the SDI-12 protocol.

Reading code:

{
    // 1. Declare an object for the sensor
    Apogee_SI411 mySensor(XTR_SOCKET_A);
     
    // 2. Turn ON the sensor
    mySensor.ON();
    
    // 3. Read the sensor. Values stored in class variables
    // Check complete code example for details
    mySensor.read();
    
    // 4. Turn off the sensor
    mySensor.OFF();
}

You can find a complete example code for reading this sensor probe in the following link: https://development.libelium.com/ag-xtr-01-si-411-sensor-reading/

Socket

Connect the SI-411 sensor probe to Plug & Sense! Smart Agriculture Xtreme in any of the sockets shown in the image below.

Figure: Available sockets for the SI-411 sensor probe

Installation

When choosing the distance of the sensor to the object to be measured at the installation of the sensor, it must be taken into account that it has a field of view (FOV) of 22º (half angle), as you can see in the image below.

It is necessary to remove the green protective cover to measure, it is only used to protect the sensor when it is not being used.

Figure: Sensor's field of view

An Angle mounting bracket (Apogee AM-220) can also be used for the installation. This accessory is recommended to mount the sensor on a pole with an outer diameter from 3.3 to 5.3 cm at different angles.

Figure: Angle mounting bracket (Apogee AM-220)

Looking into the above picture, the black plastic part on the right must be facing the pole, while the metal angled part on the left must fix the sensor.

First, attach the accessory to the pole screwing the 2 nuts just enough to hold the accessory to the pole. Keep the 2 washers to avoid the installation loosening.

Then, place the sensor into the accessory, taking into account that the sensor must point towards the desired target.

Finally, adjust the angles by rotating the sensor and hold it into the desired position while the nuts are tightened.

Figure: Angle mounting bracket installation with the SI-411 sensor

You can find the complete sensor manual on the manufacturer's website.

Application examples

• Plant canopy temperature measurement for plant water status estimation

• Road surface temperature measurement for determination of icing conditions

• Terrestrial surface (soil, vegetation, water, snow) temperature measurement in energy balance studies

Certificate of calibration

Together with this sensor we provide a calibration certificate in which the manufacturer ensures that the sensor has passed a calibration procedure with traceability to an accredited laboratory.

Leaf and flower bud temperature sensor probe (Apogee SF-421)

Frost events may happen in plants even though the ambient temperature is not 0 ºC or lower because the canopy temperature can be different than air temperature, this is called radiation frost. The Leaf and bud temperature sensor probe is designed to predict frost events.

Radiation frost occurs when there is a lack of air mixing by the wind near the surface and a negative net long wave radiation balance at the surface.

Figure: Leaf and bud temperature sensor probe (Apogee SF-421)

Specifications

• Operating temperature: -50 to 70 ºC

• Operation humidity: 0 ~ 100% RH

• Measurement range: -50 to 70 ºC

• Measurement uncertainty:

  • 0.1 ºC (from 0 to 70 ºC)

  • 0.2 ºC (from -25 to 0 ºC)

  • 0.4 ºC (from -50 to -25 ºC)

• Measurement repeatability: less than 0.05 ºC

• Stability (long-term drift): less than 0.02 ºC per year

• Equilibration time: 10 s

• Self-heating: less than 0.01 ºC

• Dimensions: 57 cm length, 2.1 cm pipe diameter, 7.0 cm disk diameter (see image below)

• Mass: 400 g

• Cable length: 5 m

Figure: Radiation frost detector dimensions

Measurement process

The SF-421 sensor provides a digital signal using the SDI-12 protocol.

Reading code:

{
    // 1. Declare an object for the sensor
    Apogee_SI421 mySensor(XTR_SOCKET_A);

    // 2. Turn ON the sensor
    mySensor.ON();

    // 3. Read the sensor. Values stored in class variables
    // Check complete code example for details
    mySensor.read();

    // 4. Turn off the sensor
    mySensor.OFF();
}

You can find a complete example code for reading this sensor probe in the following link: https://development.libelium.com/ag-xtr-02-sf-421-sensor-reading/

Socket

Connect the SF-421 sensor probe to Plug & Sense! Smart Agriculture Xtreme in any of the sockets shown in the image below.

Figure: Available sockets for the SF-421 sensor probe

Installation

The shape of the SF-421 sensor is designed to resemble a plant leaf and flower bud and be able to measure radiation frost events. The sensor should be installed near the plant canopy where the radiation frost detection is required.

Figure: SF-421 sensor installation

An Angle mounting bracket (Apogee AM-220) can also be used for the installation. This accessory is recommended to mount the sensor on a pole with an outer diameter from 3.3 to 5.3 cm in different angles.

Figure: Angle mounting bracket (Apogee AM-220)

Looking into above picture, the black plastic part on the right must be facing the pole, while the metal angled part on the left must fix the sensor.

First, attach the accessory to the pole screwing the 2 nuts just enough to hold the accessory to the pole. Keep the 2 washers to avoid the installation loosening.

Then, place the sensor into the accessory, taking into account that the sensor must point towards the desired target.

Finally, adjust the angles by rotating the sensor and hold it into the desired position while the nuts are tightened.

Figure: Angle mounting bracket installation with the SF-421 sensor

You can find the complete sensor manual on the manufacturer's website.

Application examples

• Leaf and bud temperature estimates in cropped fields, orchards, and vineyards

• Detection of potential frost damage to crops

Quality Assurance Certificate

Together with this sensor we provide a quality assurance certificate in which the manufacturer ensures that the sensor has passed the internal quality procedures.

Soil oxygen level sensor probe (Apogee SO-411 & SO-421)

Oxygen is the second major constituent of Earth's atmosphere and it is crucial for the development of life. There are sensors which measures oxygen in 2 states: dissolved in a solution and in a gaseous state. The Soil oxygen level sensor probe measures gaseous oxygen.

The Soil oxygen level sensor probe consists of a galvanic cell type sensor and offers a measure of the percentage of the total number of molecules of oxygen in the air. This sensor is specially designed for use in soil or porous media.

Figure: Soil oxygen level sensor probe (Apogee SO-411 or Apogee SO-421)

Figure: SO-411 sensor with the diffusion head AO-001, included by default

Specifications

• Operating environment: -20 to 60 ºC; 60 to 114 kPa

• Operation humidity: 0 ~ 100% RH (non-condensing)

• Measurement range: 0 to 100% O2

• Measurement repeatability: less than 0.1% of mV output at 20.95% O2

• Non-linearity: less than 1%

• Long-term drift (non-stability): 1.0 mV per year

• Oxygen consumption rate: 2.2 µmol O2 per day at 20.95% O2 and 23 ºC

• Response time: 60 s for SO-411 (14 s for SO-421)

• Dimensions: 32 mm diameter, 68 mm length

• Mass: 175 g

• Cable length: 5 m

Due to provisioning challenges with the SO-411, Libelium also distributes the SO-421 since 2021. It is an equivalent sensor, so consider this section valid for both with the next differences:

• Response time: 14 s

• Long-term drift (non-stability): 0.8 mV per year

• Shorter life (~5 years instead of 10)

Measurement process

The SO-411 and SO-421 sensors provide a digital signal using the SDI-12 protocol.

Reading code:

{
    // 1. Declare an object for the sensor
    Apogee_SO411 mySensor(XTR_SOCKET_A);

    // 2. Turn ON the sensor
    mySensor.ON();

    // 3. Initialization delay, necessary for this sensor
    delay(60000);

    // 4. Read the sensor. Values stored in class variables
    // Check complete code example for details
    mySensor.read();

    // 5. Turn off the sensor
    mySensor.OFF();
}

You can find a complete example code for reading this sensor probe in the following link: https://development.libelium.com/ag-xtr-03-so-411-sensor-reading/

And also there is a dedicated example for the SO-421 in the next link: https://development.libelium.com/ag-xtr-30-so-421-sensor-reading/

Socket

Connect the SO-411 or the SO-421 sensor probes to Plug & Sense! Smart Agriculture Xtreme in any of the sockets shown in the image below.

Figure: Available sockets for the SO-411 and SO-421 sensor probes

Installation

The SO-411 sensor is designed to be installed in soil or porous media in vertical position, with the opening pointing down and the cable pointing up.

This sensor can be used with the accessory model A0-001, designed to facilitate measurements in soil or porous media. It consists of a diffusion head that maintains an air pocket and provides protection to the teflon membrane where gas diffusion occurs.

It is highly recommended to use the SO-411 sensor probe together with the diffusion head to keep the sensor opening clear from soil and ensure accurate readings. That's why Libelium always includes the diffusion head along with the sensor probe.

There are possibilities that the SO-411 sensor is saturated by too much water, which will cause strange readings until the inner membrane of the sensor dries out. The amount of time it takes to dry out is dependent on the outside conditions (i.e humidity, temperature). Sometimes if the sensor gets dropped on a hard surface or something comparable, the sensor will also read off until it has re-stabilized itself.

Figure: Diffusion head accessory A0-001

Figure: SO-411 sensor installation with diffusion head accessory

You can find the complete sensor manual on the manufacturer\'s website.

Application examples

• Measurement of O2 in laboratory experiments

• Monitoring gaseous O2 in indoor environments for climate control

• Monitoring of O2 levels in compost piles and mine tailings

• Monitoring redox potential in soils

• Determination of respiration rates through measurement of O2 consumption in sealed chambers

• Measurement of O2 gradients in soil/porous media

Quality Assurance Certificate

Together with this sensor we provide a quality assurance certificate in which the manufacturer ensures that the sensor has passed the internal quality procedures.

Shortwave radiation sensor probe (Apogee SP-510)

The Shortwave radiation sensor probe (Apogee SP-510) measures incoming global shortwave radiation from the Sun. Shortwave radiation is radiant energy with wavelengths in the visible (VIS), near-ultraviolet (UV), and near-infrared (NIR) spectra.

This sensor consists of a thermopile detector, acrylic diffuser, heater, and signal processing circuitry mounted in an anodized aluminum housing.

Figure: Shortwave radiation sensor probe (Apogee SP-510)

Specifications

• Operating temperature: -50 to 80 ºC

• Operation humidity: 0 ~ 100% RH

• Sensitivity (variable from sensor to sensor, typical values listed): 0.057 mV per W m^-2

• Calibration factor (reciprocal of sensitivity): 17.5 W m^-2 per mV

• Calibration uncertainty: ± 5%

• Calibrated output range: 0 to 114 mV

• Measurement range: 0 to 2000 W m^-2 (net shortwave radiation)

• Measurement repeatability: less than 1%

• Long-term drift (non-stability): less than 2% per year

• Non-linearity: less than 1%

• Detector response time: 0.5 s

• Field of view: 180º

• Spectral range (wavelengths where response is 50% of maximum): 385 to 2105 nm

• Directional (cosine) response: less than 30 W m^-2 up to solar zenith angles of 80º

• Temperature response: less than 5% from -15 to 45 ºC

• Cable length: 5 m

Measurement process

The SP-510 sensor provides an analog signal.

Reading code:

{
    // 1. Declare an object for the sensor
    Apogee_SP510 mySensor(XTR_SOCKET_B);

    // 2. Turn ON the sensor
    mySensor.ON();

    // 3. Read the sensor. Values stored in class variables
    // Check complete code example for details
    mySensor.read();

    // 4. Turn off the sensor
    mySensor.OFF();
}

You can find a complete example code for reading this sensor probe in the following link: https://development.libelium.com/ag-xtr-06-sp-510-sensor-reading/

Socket

Connect the SP-510 sensor probe to Plug & Sense! Smart Agriculture Xtreme in any of the sockets shown in the image below.

Figure: Available sockets for the SP-510 sensor probe

Installation

The SP-510 sensor includes a nylon mounting screw on the base in order to mount the sensor on a solid surface.

Figure: Pyranometer installation

The Solar sensors mounting accessory can also be used for the installation. This accessory is optional but highly recommended for the solar sensors. With this accessory you will get a secure fastening while keeping the sensor as level as possible, always pointing up.

The accessory is composed of 2 main parts: A - Mounting bracket: it will be fastened to a pipe or mast with its u-bolt B - Leveling plate: it holds the sensor and includes a bubble level

Figure: Solar sensors mounting accessory

Mounting the system is very easy, just follow these steps: 1 - Attach the solar sensor to the leveling plate, in its central hole. Use the black nylon screw (every sensor comes with one, find it on its bottom) and a screwdriver. 2 - Fasten the leveling plate to the mounting bracket with the 3 long gray screws. Do not insert them too firmly, the final adjustment is done later. 3 - Decide if you want to mount the whole structure to a vertical or horizontal pipe or mast (its outer diameter can go from 3.3 to 5.3 cm). Depending on horizontal or vertical configuration, you will use the bottom or the side of the mounting bracket. 4 - Place the black plastic piece in contact with the pipe. Then use the u-bolt to grab the mounting bracket to the pipe. On both ends of the u-bolt, insert first the washers, then the lock washers and finally the nuts. 5 - Place the structure in the desired position and tighten the nuts firmly with a wrench.

Figure: Final look of the whole structure

6 - You may take advantage of the holes on the mounting bracket and the pipe to secure the cable of the sensor, avoiding its rotation. You can do that with some cable ties. To minimize azimuth error, the sensor should be mounted with the cable pointing toward true north in the northern hemisphere or true south in the southern hemisphere. Azimuth error is typically less than 1%, but it is easy to minimize by proper cable orientation.7 - Once installed, use the long gray screws of the plate for fine adjustment of the level, making sure the bubble is inside the black circle. The wave spring will keep the leveling plate in place.

The sensor should be mounted so that obstructions (pipe/mast, sensors, enclosures, leaves, walls, etc) do not shade the sensor.

You can find the complete sensor manual on the manufacturer's website.

Application examples

• Incoming shortwave radiation measurement in agricultural, ecological, and hydrological weather networks

• Optimization of photo-voltaic systems

Certificate of calibration

Together with this sensor we provide a calibration certificate in which the manufacturer ensures that the sensor has passed a calibration procedure with traceability to an accredited laboratory.

Solar radiation sensor probe for Smart Agriculture Xtreme (Apogee SQ-110)

Photosynthetically active radiation (PAR) is the radiation that drives photosynthesis and is typically defined as total radiation across a range from 400 to 700 nm. PAR is often expressed as photosynthetic photon flux density (PPFD): photon flux in units of micromoles per square meter per second (μmol·m^-2·s^-1).

Until July 2021, Libelium distributed this sensor, but it was discontinued by Apogee.

From July 2021, Libelium only offers the SQ-100x sensor for PAR metering, which replaces the SQ-110 and has a slightly better performace.

Figure: Solar radiation sensor probe for Smart Agriculture Xtreme (Apogee SQ-110)

Figure: Graph of the spectral response of the PAR sensor (Apogee SQ-110) compared to the photosynthetic response of a plant

Specifications

• Operation temperature: -40 ~ 70 ºC

• Operation humidity: 0 ~ 100% RH

• Sensitivity: 0.2 mV / μmol·m^-2·s^-1

• Calibration factor (reciprocal of sensitivity): 5 μmol·m^-2·s^-1 / mV

• Non-linearity: < 1% (up to 4000 μmol·m^-2·s^-1 / mV)

• Non-stability (long-term drift): <2% per year

• Spectral range: 410 ~ 655 nm

• Repeatability: <0.5%

• Diameter: 2.4 cm

• Height: 2.8 cm

• Cable length: 5 m

Measurement process

The SQ-110 sensor provides an analog signal.

Reading code:

{
    // 1. Declare an object for the sensor
    Apogee_SQ110 mySensor(XTR_SOCKET_B);

    // 2. Turn ON the sensor
    mySensor.ON();

    // 3. Read the sensor. Values stored in class variables
    // Check complete code example for details
    mySensor.read();

    // 4. Turn off the sensor
    mySensor.OFF();
}

You can find a complete example code for reading this sensor probe in the following link: https://development.libelium.com/ag-xtr-05-sq-110-sensor-reading/

Socket

Connect the SQ-110 sensor probe to Plug & Sense! Smart Agriculture Xtreme in any of the sockets shown in the image below.

This sensor has a specific wiring for the Plug & Sense! Smart Agriculture Xtreme model, so it is not compatible with other Plug & Sense! models and vice versa. Refer to our Sales department for more information.

Figure: Available sockets for the SQ-110 sensor probe

Installation

The SQ-110 sensor includes a nylon mounting screw on the base in order to mount the sensor on a solid surface.

Figure: SQ-110 sensor installation

The Solar sensors mounting accessory can also be used for the installation. This accessory is optional but highly recommended for the solar sensors. With this accessory you will get a secure fastening while keeping the sensor as level as possible, always pointing up.

The accessory is composed of 2 main parts: A - Mounting bracket: it will be fastened to a pipe or mast with its u-bolt B - Leveling plate: it holds the sensor and includes a bubble level

Figure: Solar sensors mounting accessory

Mounting the system is very easy, just follow these steps: 1 - Attach the solar sensor to the leveling plate, in its central hole. Use the black nylon screw (every sensor comes with one, find it on its bottom) and a screwdriver. 2 - Fasten the leveling plate to the mounting bracket with the 3 long gray screws. Do not insert them too firmly, the final adjustment is done later. 3 - Decide if you want to mount the whole structure to a vertical or horizontal pipe or mast (its outer diameter can go from 3.3 to 5.3 cm). Depending on horizontal or vertical configuration, you will use the bottom or the side of the mounting bracket. 4 - Place the black plastic piece in contact with the pipe. Then use the u-bolt to grab the mounting bracket to the pipe. On both ends of the u-bolt, insert first the washers, then the lock washers and finally the nuts. 5 - Place the structure in the desired position and tighten the nuts firmly with a wrench.

Figure: Final look of the whole structure

6 - You may take advantage of the holes on the mounting bracket and the pipe to secure the cable of the sensor, avoiding its rotation. You can do that with some cable ties. To minimize azimuth error, the sensor should be mounted with the cable pointing toward true north in the northern hemisphere or true south in the southern hemisphere. Azimuth error is typically less than 1%, but it is easy to minimize by proper cable orientation. 7 - Once installed, use the long gray screws of the plate for fine adjustment of the level, making sure the bubble is inside the black circle. The wave spring will keep the leveling plate in place.

The sensor should be mounted so that obstructions (pipe/mast, sensors, enclosures, leaves, walls, etc) do not shade the sensor.

You can find the complete sensor manual on the manufacturer's website.

Application examples

Photosynthetic photon flux density (PPFD) measures in:

• Plant canopies in outdoor environments

• Greenhouses and growth chambers

• Evapotranspiration analysis

• Aquatic environments, including salt water aquariums where corals are grown

Certificate of calibration

Together with this sensor we provide a calibration certificate in which the manufacturer ensures that the sensor has passed a calibration procedure with traceability to an accredited laboratory.

Solar radiation sensor probe for Smart Agriculture Xtreme (Apogee SQ-100x)

Photosynthetically active radiation (PAR) is the radiation that drives photosynthesis and is typically defined as total radiation across a range from 400 to 700 nm. PAR is often expressed as photosynthetic photon flux density (PPFD): photon flux in units of micromoles per square meter per second (μmol·m^-2·s^-1).

Figure: Solar radiation sensor probe for Smart Agriculture Xtreme (Apogee SQ-100x)

Specifications

• Operation temperature: -40 ~ 60 ºC

• Operation humidity: 0 ~ 100% RH

• Sensitivity: 0.1 mV / μmol·m^-2·s^-1

• Calibration factor (reciprocal of sensitivity): 10 μmol·m^-2·s^-1 / mV

• Non-linearity: < 1% (up to 4000 μmol·m^-2·s^-1 / mV)

• Non-stability (long-term drift): <2% per year

• Spectral range: 370 ~ 650 nm

• Repeatability: <0.5%

• Diameter: 2.4 cm

• Height: 3.3 cm

• Cable length: 5 m

Figure: Graph of the spectral response of the PAR sensor (Apogee SQ-100x) compared to the photosynthetic response of a plant

Measurement process

The SQ-100x sensor provides an analog signal.

Reading code:

{
    // 1. Declare an object for the sensor
    Apogee_SQ100x mySensor(XTR_SOCKET_B);

    // 2. Turn ON the sensor
    mySensor.ON();

    // 3. Read the sensor. Values stored in class variables
    // Check complete code example for details
    mySensor.read();

    // 4. Turn off the sensor
    mySensor.OFF();
}

You can find a complete example code for reading this sensor probe in the following link: https://development.libelium.com/ag-xtr-05b-sq-100-x-sensor-reading/

Socket

Connect the SQ-100x sensor probe to Plug & Sense! Smart Agriculture Xtreme in any of the sockets shown in the image below.

This sensor has a specific wiring for the Plug & Sense! Smart Agriculture Xtreme model, so it is not compatible with other Plug & Sense! models and vice versa. Refer to our Sales department for more information.

Figure: Available sockets for the SQ-100x sensor probe

Installation

The SQ-100x sensor includes a nylon mounting screw on the base in order to mount the sensor on a solid surface.

Figure: SQ-100x sensor installation

The Solar sensors mounting accessory can also be used for the installation. This accessory is optional but highly recommended for the solar sensors. With this accessory you will get a secure fastening while keeping the sensor as level as possible, always pointing up.

The accessory is composed of 2 main parts: A - Mounting bracket: it will be fastened to a pipe or mast with its u-bolt B - Leveling plate: it holds the sensor and includes a bubble level

Figure: Solar sensors mounting accessory

Mounting the system is very easy, just follow these steps: 1 - Attach the solar sensor to the leveling plate, in its central hole. Use the black nylon screw (every sensor comes with one, find it on its bottom) and a screwdriver. 2 - Fasten the leveling plate to the mounting bracket with the 3 long gray screws. Do not insert them too firmly, the final adjustment is done later. 3 - Decide if you want to mount the whole structure to a vertical or horizontal pipe or mast (its outer diameter can go from 3.3 to 5.3 cm). Depending on horizontal or vertical configuration, you will use the bottom or the side of the mounting bracket. 4 - Place the black plastic piece in contact with the pipe. Then use the u-bolt to grab the mounting bracket to the pipe. On both ends of the u-bolt, insert first the washers, then the lock washers and finally the nuts. 5 - Place the structure in the desired position and tighten the nuts firmly with a wrench.

Figure: Final look of the whole structure

6 - You may take advantage of the holes on the mounting bracket and the pipe to secure the cable of the sensor, avoiding its rotation. You can do that with some cable ties. To minimize azimuth error, the sensor should be mounted with the cable pointing toward true north in the northern hemisphere or true south in the southern hemisphere. Azimuth error is typically less than 1%, but it is easy to minimize by proper cable orientation. 7 - Once installed, use the long gray screws of the plate for fine adjustment of the level, making sure the bubble is inside the black circle. The wave spring will keep the leveling plate in place.

The sensor should be mounted so that obstructions (pipe/mast, sensors, enclosures, leaves, walls, etc) do not shade the sensor.

You can find the complete sensor manual on the manufacturer's website.

Application examples

Photosynthetic photon flux density (PPFD) measures in:

• Plant canopies in outdoor environments

• Greenhouses and growth chambers

• Evapotranspiration analysis

• Aquatic environments, including salt water aquariums where corals are grown

Certificate of calibration

Together with this sensor we provide a calibration certificate in which the manufacturer ensures that the sensor has passed a calibration procedure with traceability to an accredited laboratory.

Ultraviolet radiation sensor probe for Smart Agriculture Xtreme (Apogee SU-100)

Ultraviolet (UV) radiation is typically defined as total radiation across a range from 100 to 400 nm and is subdivided into 3 wavelength ranges: UV-A (315 to 400 nm), UV-B (280 to 315 nm) and UV-C (100 to 280 nm). Much of the UV-B and all of the UV-C wavelengths from the sun are absorbed by the Earth's atmosphere.

The Ultraviolet radiation sensor probe for Smart Agriculture Xtreme (Apogee SU-100) detects UV radiation from 250 to 400 nm and is calibrated in photon flux units of micromoles per square meter per second (μmol·m^-2·s^-1).

Note: Apogee has recently updated its ultraviolet sensors. The new SU-202 sensor is the substitute for the SU-100, which is no longer available for purchase.

Figure: Ultraviolet radiation sensor probe for Smart Agriculture Xtreme (Apogee SU-100)

Figure: Graph of the spectral response of the SU-100 sensor probe compared to the photosynthetic response of a plant

Specifications

• Operation temperature: -40 to 70 ºC

• Operation humidity: 0 to 100%

• Sensitivity: 0.2 mV / μmol·m^-2·s^-1

• Calibration factor (reciprocal of sensitivity): 5.0 μmol·m^-2·s^-1 / mV

• Non-stability (long-term drift): <3% per year

• Non-linearity: <1% (up to 300 μmol·m^-2·s^-1)

• Spectral range: 250 ~ 400 nm

• Repeatability: <1%

• Diameter: 2.4 cm

• Height: 2.8 cm

• Cable length: 5 m

Measurement process

The SU-100 sensor provides an analog signal.

Reading code:

{
    // 1. Declare an object for the sensor
    Apogee_SU100 mySensor(XTR_SOCKET_B);

    // 2. Turn ON the sensor
    mySensor.ON();

    // 3. Read the sensor. Values stored in class variables
    // Check complete code example for details
    mySensor.read();

    // 4. Turn off the sensor
    mySensor.OFF();
}

You can find a complete example code for reading this sensor probe in the following link: https://development.libelium.com/ag-xtr-04-su-100-sensor-reading/

Socket

Connect the SU-100 sensor probe to Plug & Sense! Smart Agriculture Xtreme in any of the sockets shown in the image below.

This sensor has a specific wiring for the Plug & Sense! Smart Agriculture Xtreme model, so it is not compatible with other Plug & Sense! models and vice versa. Refer to our Sales department for more information.

Figure: Available sockets for the SU-100 sensor probe

Installation

The SU-100 sensor includes a nylon mounting screw on the base in order to mount the sensor on a solid surface.

Figure: SU-100 sensor probe installation

The Solar sensors mounting accessory can also be used for the installation. This accessory is optional but highly recommended for the solar sensors. With this accessory you will get a secure fastening while keeping the sensor as level as possible, always pointing up.

The accessory is composed of 2 main parts: A - Mounting bracket: it will be fastened to a pipe or mast with its u-bolt. B - Leveling plate: it holds the sensor and includes a bubble level.

Figure: Solar sensors mounting accessory

Mounting the system is very easy, just follow these steps: 1 - Attach the solar sensor to the leveling plate, in its central hole. Use the black nylon screw (every sensor comes with one, find it on its bottom) and a screwdriver. 2 - Fasten the leveling plate to the mounting bracket with the 3 long gray screws. Do not insert them too firmly, the final adjustment is done later. 3 - Decide if you want to mount the whole structure to a vertical or horizontal pipe or mast (its outer diameter can go from 3.3 to 5.3 cm). Depending on horizontal or vertical configuration, you will use the bottom or the side of the mounting bracket. 4 - Place the black plastic piece in contact with the pipe. Then use the u-bolt to grab the mounting bracket to the pipe. On both ends of the u-bolt, insert first the washers, then the lock washers and finally the nuts. 5 - Place the structure in the desired position and tighten the nuts firmly with a wrench.

Figure: Final look of the whole structure

6 - You may take advantage of the holes on the mounting bracket and the pipe to secure the cable of the sensor, avoiding its rotation. You can do that with some cable ties. To minimize azimuth error, the sensor should be mounted with the cable pointing toward true north in the northern hemisphere or true south in the southern hemisphere. Azimuth error is typically less than 1%, but it is easy to minimize by proper cable orientation. 7 - Once installed, use the long gray screws of the plate for fine adjustment of the level, making sure the bubble is inside the black circle. The wave spring will keep the leveling plate in place.

The sensor should be mounted so that obstructions (pipe/mast, sensors, enclosures, leaves, walls, etc) do not shade the sensor.

You can find the complete sensor manual on the manufacturer's website.

Application examples

UV radiation measurement in:

• Outdoor environments

• Laboratory use with artificial light sources (e.g. germicidal lamps)

• Monitoring the filter ability and stability of different materials

Certificate of calibration

Together with this sensor we provide a calibration certificate in which the manufacturer ensures that the sensor has passed a calibration procedure with traceability to an accredited laboratory.

Ultraviolet radiation sensor probe for Smart Agriculture Xtreme (Apogee SU-202)

Apogee has recently updated its ultraviolet sensors. The new SU-202 sensor is the substitute for the SU-100, which is discontinued. It is available for the Smart Agriculture Xtreme line.

The Ultraviolet radiation sensor probe for Smart Agriculture Xtreme (Apogee SU-202) detects UV radiation from 300 to 400 nm and is calibrated in photon flux units of micromoles per square meter per second (μmol·m-2s-1).

Figure: Ultraviolet radiation sensor probe for Smart Agriculture Xtreme (Apogee SU-202)

Figure: Graph of the spectral response of the SU-202 compared to the photosynthetic response of a plant

Specifications

• Operation temperature: -30 to 85 ºC

• Operation humidity: 0 to 100%

• Temperature response: -0.1% per ºC

• Sensitivity: 8.33 mV / μmol·m^-2·s^-1

• Calibration factor (reciprocal of sensitivity): 0.12 μmol·m^-2·s^-1 / mV

• Calibration uncertainty: ±10%

• Spectral range: 300 ~ 400 nm (wavelengths where response is greater than 10 % of maximum)

• Measurement range: 0 to 100 Wm−2

• Repeatability: <0.5%

• Long-term drift: Less than 2% per year

• Non-linearity: Less than 1%

• Field overview: 180º

• Directional (cosine) response: ±2% at 45º; ± 5 % at 75º zenith angle

• Dimensions: 30.5 mm diameter, 37 mm height

Measurement process

The SU-202 sensor provides an analog signal.

Reading code:

{
    // 1. Declare an object for the sensor
    Apogee_SU202 mySensor(XTR_SOCKET_B);

    // 2. Turn ON the sensor
    mySensor.ON();

    // 3. Read the sensor. Values stored in class variables
    // Check complete code example for details
    mySensor.read();

    // 4. Turn off the sensor
    mySensor.OFF();
}

You can find a complete example code for reading this sensor probe in the following link: https://development.libelium.com/ag-xtr-29-su-202-sensor-reading/

Socket

Connect the SU-202 sensor probe to Plug & Sense! Smart Agriculture Xtreme in any of the sockets shown in the image below.

This sensor specific wiring for the Plug & Sense! Smart Agriculture Xtreme model, so it is not compatible with other Plug & Sense! models and vice versa. Refer to our Sales department for more information.

Figure: Available sockets for the SU-202 sensor probe

Installation

The SU-202 sensor includes a nylon mounting screw on the base in order to mount the sensor on a solid surface.

Figure: SU-202 sensor probe installation

The Solar sensors mounting accessory can also be used for the installation. This accessory is optional but highly recommended for the solar sensors. With this accessory you will get a secure fastening while keeping the sensor as level as possible, always pointing up.

The accessory is composed of 2 main parts: A - Mounting bracket: it will be fastened to a pipe or mast with its u-bolt. B - Leveling plate: it holds the sensor and includes a bubble level.

Figure: Solar sensors mounting accessory

Mounting the system is very easy, just follow these steps: 1 - Attach the solar sensor to the leveling plate, in its central hole. Use the black nylon screw (every sensor comes with one, find it on its bottom) and a screwdriver. 2 - Fasten the leveling plate to the mounting bracket with the 3 long gray screws. Do not insert them too firmly, the final adjustment is done later. 3 - Decide if you want to mount the whole structure to a vertical or horizontal pipe or mast (its outer diameter can go from 3.3 to 5.3 cm). Depending on the horizontal or vertical configuration, you will use the bottom or the side of the mounting bracket. 4 - Place the black plastic piece in contact with the pipe. Then use the u-bolt to grab the mounting bracket to the pipe. On both ends of the u-bolt, insert first the washers, then the lock washers and finally the nuts. 5 - Place the structure in the desired position and tighten the nuts firmly with a wrench.

Figure: Final look of the whole structure

6 - You may take advantage of the holes on the mounting bracket and the pipe to secure the cable of the sensor, avoiding its rotation. You can do that with some cable ties. To minimize azimuth error, the sensor should be mounted with the cable pointing toward true north in the northern hemisphere or true south in the southern hemisphere. Azimuth error is typically less than 1%, but it is easy to minimize by proper cable orientation. 7 - Once installed, use the long gray screws of the plate for fine adjustment of the level, making sure the bubble is inside the black circle. The wave spring will keep the leveling plate in place.

The sensor should be mounted so that obstructions (pipe/mast, sensors, enclosures, leaves, walls, etc) do not shade the sensor.

You can find the complete sensor manual on the manufacturer's website.

Application examples

UV radiation measurement in:

• Outdoor environments

• Laboratory use with artificial light sources (e.g. germicidal lamps)

• Monitoring the filter ability and stability of different materials

Certificate of calibration

Together with this sensor, we provide a calibration certificate in which the manufacturer ensures that the sensor has passed a calibration procedure with traceability to an accredited laboratory.

Temperature, humidity and pressure sensor probe (Bosch BME280)

The Bosch BME280 includes a humidity sensor that features an extremely fast response time which supports performance requirements for emerging applications such as context awareness, and high accuracy over a wide temperature range. The pressure sensor is an absolute barometric pressure sensor with features exceptionally high accuracy and resolution at very low noise. The integrated temperature sensor has been optimized for very low noise and high resolution. It is primarily used for temperature compensation of the pressure and humidity sensors, and can also be used for estimating ambient temperature.

Figure: Temperature, humidity and pressure sensor (Bosch BME280)

Specifications

Temperature sensor

• Operational range: -40 ~ +85 ºC

• Full accuracy range: 0 ~ +65 ºC

• Accuracy: ±1 ºC (range 0 ºC ~ +65 ºC)

• Response time: 1.65 seconds (63% response from +30 to +125 °C)

Humidity sensor

• Measurement range: 0 ~ 100% of relative humidity (for temperatures < 0 °C and > 60 °C see figure below) Accuracy: < ±3% RH (at 25 ºC, range 20 ~ 80%)

• Hysteresis: ±1% RH

• Operating temperature: -40 ~ +85 ºC

• Response time (63% of step 90% to 0% or 0% to 90%): 1 second

Figure: Humidity sensor operating range

Pressure sensor

• Measurement range: 30 ~ 110 kPa

• Operational temperature range: -40 ~ +85 ºC

• Full accuracy temperature range: 0 ~ +65 ºC

• Absolute accuracy: ±0.1 kPa (0 ~ 65 ºC)

Measurement process

The Temperature, humidity and pressure sensor provides a digital signal using the I2C protocol.

Reading code:

{
    // 1. Declare an object for the sensor
    bme mySensor(XTR_SOCKET_A);

    // 2. Turn ON the sensor
    mySensor.ON();

    // 3. Read the sensor. Store parameters in local variables
    float temperature = mySensor.getTemperature();
    float humidity = mySensor.getHumidity();
    float pressure = mySensor.getPressure();

    // 4. Turn off the sensor
    mySensor.OFF();
}

You can find a complete example code for reading this sensor probe in the following link: https://development.libelium.com/ag-xtr-16-bme280-sensor-reading/

Socket

Connect the Temperature, humidity and pressure sensor probe (Bosch BME280) to Plug & Sense! Smart Agriculture Xtreme in any of the sockets shown in the image below.

Figure: Available sockets for the Temperature, humidity and pressure sensor probe (Bosch BME280)

Application examples

• Weather observation and forecast

• Evapotranspiration analysis

• Control heating, ventilation or air conditioning in greenhouses

• Warning regarding dryness or high temperatures

Conductivity, water content and soil temperature GS3 sensor probe (Decagon GS3)

This sensor probe was discontinued by Libelium in July 2020 since it was discontinued by its manufacturer. From that moment, our customers can choose the equivalent TEROS 11 and TEROS 12 sensor probes.

The Conductivity, water content and soil temperature sensor probe (Decagon GS3) can measure many types of growing media, specially in greenhouse applications where the probe can be inserted easily into different types of soilless substrates. The GS3 sensor determines volumetric water content (VWC) by measuring the dielectric constant (εa) of the medium using capacitance / frequency-domain technology, the temperature using a thermistor, and electrical conductivity using a stainless steel electrode array.

Figure: Conductivity, water content and soil temperature GS3 sensor probe (Decagon GS3)

Specifications

General specifications

• Operating temperature: -40 to 60 ºC

• Dielectric measurement frequency: 70 MHz

• Measurement time: 150 ms

• Dimensions: 9.3 x 2.4 x 6.5 cm

• Prong length: 5.5 cm

• Cable length: 5 m

Volumetric water content

• Accuracy: εa: ±1 εa (unitless) from 1 to 40 (soil range), ±15% from 40 to 80

• Resolution:

  • 0.1 εa (unitless) from 1 to 20

  • < 0.75 εa (unitless) from 20 to 80

  • 0.002 m³/m³ (0.2% VWC) from 0 to 40% VWC

  • 0.001 m³/m³ (0.1% VWC) > 40% VWC

• Range: Apparent dielectric permittivity (εa): 1 (air) to 80 (water)

Bulk electrical conductivity

• Accuracy: ± 5% from 0 to 5 dS/m, ±10% from 5 to 23 dS/m

• Resolution: 0.001 dS/m from 0 to 23 dS/m

• Range: 0 to 25 dS/m (bulk)

Temperature

• Accuracy: ±1 ºC

• Resolution: 0.1 ºC

• Range: -40 to 60 ºC

Measurement process

The GS3 sensor provides a digital signal using the SDI-12 protocol.

Reading code:

{
    // 1. Declare an object for the sensor
    Decagon_GS3 mySensor(XTR_SOCKET_A);

    // 2. Turn ON the sensor
    mySensor.ON();

    // 3. Read the sensor. Values stored in class variables
    // Check complete code example for details
    mySensor.read();

    // 4. Turn off the sensor
    mySensor.OFF();
}

Volumetric water content (VWC) calculation

The GS3 sensor provides the dielectric permittivity (ε~) of the surrounding medium. The dielectric permittivity value must be converted in the code to a particular substrate by a calibration equation specific to the media you are working in.

The calibration equation for several potting soils, perlite, and peat moss at salinities ranging from 0 to > 4 dS/m is:

$$VWC(m³/m³) =0.118*sqrt(εa) - 0.117$$

The calibration equation for mineral soils ranging from 0 to > 5 dS/m is:

$$VWC(m³/m³) = 5.89*10⁻⁶*εa³-7.62*10⁻⁴*εa²+3.67*10⁻²*εa-7.53*10⁻²$$

You can find a complete example code for reading this sensor probe and for calculating VWC for mineral soil in the following link: https://development.libelium.com/ag-xtr-07-gs3-sensor-reading/

Socket

Connect the GS3 sensor probe to Plug & Sense! Smart Agriculture Xtreme in any of the sockets shown in the image below.

Figure: Available sockets for the GS3 sensor probe

Installation

The GS3 sensor can be inserted into soilless substrates in different ways. However, the orientation of the sensor does affect the sensor readings. Please keep in mind that the sensor only measures the VWC in its sphere of influence.

Sensors can either be inserted into the top of the plant pot or into the side of the root ball. Insertion into the side of the root ball may be the best option, as it will give the best indication of the water available to the plant.

Figure: GS3 sensor installation

You can find the complete sensor manual on the manufacturer's website.

Application examples

• Maintain good soil contact and compensate for air gaps in the substrate of potting soil or soilless medias

• Greenhouse substrate monitoring

• Irrigation management

• Salt management

• Fertilizer movement

• Modeling processes that are affected by temperature

Quality Assurance Certificate

Together with this sensor we provide a quality assurance certificate in which the manufacturer ensures that the sensor has passed the internal quality procedures.

Volumetric water content and soil temperature TEROS 11 sensor probe (Meter TEROS 11)

The Volumetric water content and soil temperature sensor probe (Meter TEROS 11) can measure many types of growing media, especially in greenhouse applications where the probe can be inserted easily into different types of soilless substrates. The TEROS 11 sensor determines volumetric water content (VWC) using capacitance / frequency-domain technology and the temperature using a thermistor.

Figure: Volumetric water content and soil temperature TEROS 11 sensor probe (Meter TEROS 11)

Specifications

General specifications

• Operating temperature: -40 to 60 ºC

• Dielectric measurement frequency: 70 MHz

• Measurement time: 150 ms (maximum)

• Dimensions: 9.4 x 2.4 x 7.5 cm

• Needle length: 5.5 cm

• Cable length: 5 m

Volumetric water content

• Accuracy: ±0.03 m³/m³ typical in mineral soils that have solution electrical conductivity < 8 dS/m

• Resolution: 0.001 m³/m³

• Range: Mineral soil calibration: 0.00-0.70 m³/m³; Soilless media calibration: 0.0-1.0 m³/m³

The VWC range is dependent on the media the sensor is calibrated to. A custom calibration will accommodate the necessary ranges for most substrates.

Temperature

• Accuracy: ±1 ºC from -40 to 0 ºC, ±0.5 ºC from 0 to 60 ºC

• Resolution: 0.1 ºC

• Range: -40 to 60 ºC

Measurement process

The TEROS 11 sensor provides a digital signal using the SDI-12 protocol.

Reading code:

{
    // 1. Declare an object for the sensor
    Meter_TEROS11 mySensor(XTR_SOCKET_A);

    // 2. Turn ON the sensor
    mySensor.ON();

    // 3. Read the sensor. Values stored in class variables
    // Check complete code example for details
    mySensor.read();

    // 4. Turn off the sensor
    mySensor.OFF();
}

Volumetric water content (VWC) calculation

The TEROS 11 sensor provides a raw output to calculate the VWC and the dielectric permittivity (εa) of the surrounding medium. The VWC value must be converted in the code to a particular substrate by a calibration equation specific to the media you are working in.

The calibration equation for several potting soils, perlite, and peat moss at salinities is:

$$VWC(m³/m³) = 6.771*10⁻¹⁰*RAW³-5.105*10⁻⁶*RAW²+1.302*10⁻²*RAW-10.848$$

The calibration equation for mineral soils ranging from 0 to to 8 dS/m is:

$$VWC(m³/m³) = 5.89*10⁻⁶*εa³-7.62*10⁻⁴*εa²+3.67*10⁻²*εa-7.53*10⁻²$$

Dielectric Permittivity calculation (ε)

Dielectric Permittivity is calculated from the raw output following the next equation:

$$ε = (2.887*10⁻⁹*RAW³-2.080*10⁻⁵*RAW²+5.276*10⁻²*RAW-43.39)²$$

You can find complete example code for reading this sensor probe and for calculating VWC and Dielectric Permittivity in the following link: https://development.libelium.com/ag-xtr-27-teros-11-sensor-reading/

Socket

Connect the TEROS 11 sensor probe to Plug & Sense! Smart Agriculture Xtreme in any of the sockets shown in the image below.

Figure: Available sockets for the TEROS 11 sensor probe

Installation

The TEROS 11 sensor can be inserted into soilless substrates in different ways. However, the orientation of the sensor does affect the sensor readings. Please keep in mind that the sensor only measures the VWC in its sphere of influence.

Sensors can either be inserted into the top of the plant pot or into the side of the root ball. Insertion into the side of the root ball may be the best option, as it will give the best indication of the water available to the plant.

Figure: TEROS 11 sensor installation

You can find the complete sensor manual on the manufacturer's website.

Application examples

• Maintain good soil contact and compensate for air gaps in the substrate of potting soil or soilless media

• Greenhouse substrate monitoring

• Irrigation management

• Modeling processes that are affected by temperature

Quality Assurance Certificate

Together with this sensor, we provide a quality assurance certificate in which the manufacturer ensures that the sensor has passed the internal quality procedures.

Conductivity, water content and soil temperature TEROS 12 sensor probe (Meter TEROS 12)

The Conductivity, water content and soil temperature sensor probe (Meter TEROS 12) can measure many types of growing media, especially in greenhouse applications where the probe can be inserted easily into different types of soilless substrates. The TEROS 12 sensor determines volumetric water content (VWC) using capacitance / frequency-domain technology, the temperature using a thermistor, and electrical conductivity using a stainless steel electrode array.

‌ Figure: Conductivity, water content and soil temperature TEROS 12 sensor probe (Meter TEROS 12)

Specifications

General specifications

• Operating temperature: -40 to 60 ºC

• Dielectric measurement frequency: 70 MHz

• Measurement time: 150 ms (maximum)

• Dimensions: 9.4 x 2.4 x 7.5 cm

• Needle length: 5.5 cm

• Cable length: 5 m

Volumetric water content

• Accuracy: ±0.03 m³/m³ typical in mineral soils that have solution electrical conductivity < 8 dS/m

• Resolution: 0.001 m³/m³

• Range: Mineral soil calibration: 0.00-0.70 m³/m³; Soilless media calibration: 0.0-1.0 m³/m³

The VWC range is dependent on the media the sensor is calibrated to. A custom calibration will accommodate the necessary ranges for most substrates.

Electrical conductivity

• Accuracy: ± 5% from 0 to 10 dS/m, ±10% from 10 to 20 dS/m

• Resolution: 0.001 dS/m

• Range: 0 to 20 dS/m (bulk)

Temperature

• Accuracy: ±0.5 ºC from -40 to 0 ºC, ±0.3 ºC from 0 to 60 ºC

• Resolution: 0.1 ºC

• Range: -40 to 60 ºC

Measurement process

The TEROS 12 sensor provides a digital signal using the SDI-12 protocol.

Reading code:

{
    // 1. Declare an object for the sensor
    Meter_TEROS12 mySensor(XTR_SOCKET_A);

    // 2. Turn ON the sensor
    mySensor.ON();

    // 3. Read the sensor. Values stored in class variables
    // Check complete code example for details
    mySensor.read();

    // 4. Turn off the sensor
    mySensor.OFF();
}

Volumetric water content (VWC) calculation

The TEROS 12 sensor provides a raw output to calculate the VWC and the dielectric permittivity (εa) of the surrounding medium. The VWC value must be converted in the code to a particular substrate by a calibration equation specific to the media you are working in.

The calibration equation for several potting soils, perlite, and peat moss at salinities is:

$$VWC(m³/m³) = 6.771*10⁻¹⁰*RAW³-5.105*10⁻⁶*RAW²+1.302*10⁻²*RAW-10.848$$

The calibration equation for mineral soils ranging from 0 to to 8 dS/m is:

$$VWC(m³/m³) = 5.89*10⁻⁶*εa³-7.62*10⁻⁴*εa²+3.67*10⁻²*εa-7.53*10⁻²$$

Dielectric Permittivity calculation (ε)

Dielectric Permittivity is calculated from the raw output following the next equation:

$$ε = (2.887*10⁻⁹*RAW³-2.080*10⁻⁵*RAW²+5.276*10⁻²*RAW-43.39)²$$

You can find complete example code for reading this sensor probe and for calculating VWC and Dielectric Permittivity in the following link: https://development.libelium.com/ag-xtr-28-teros-12-sensor-reading/

Socket

Connect the TEROS 12 sensor probe to Plug & Sense! Smart Agriculture Xtreme in any of the sockets shown in the image below.

Figure: Available sockets for the TEROS 12 sensor probe

Installation

The TEROS 12 sensor can be inserted into soilless substrates in different ways. However, the orientation of the sensor does affect the sensor readings. Please keep in mind that the sensor only measures the VWC in its sphere of influence.

Sensors can either be inserted into the top of the plant pot or into the side of the root ball. Insertion into the side of the root ball may be the best option, as it will give the best indication of the water available to the plant.

Figure: TEROS 12 sensor installation

You can find the complete sensor manual on the manufacturer's website.

Application examples

• Maintain good soil contact and compensate for air gaps in the substrate of potting soil or soilless media

• Greenhouse substrate monitoring

• Irrigation management

• Salt management

• Fertilizer movement

• Modeling processes that are affected by temperature

Quality Assurance Certificate

Together with this sensor, we provide a quality assurance certificate in which the manufacturer ensures that the sensor has passed the internal quality procedures.

Conductivity, water content and soil temperature 5TE sensor probe (Decagon 5TE)

This sensor probe was discontinued by Libelium in July 2020 since it was discontinued by its manufacturer. From that moment, our customers can choose the equivalent TEROS 11 and TEROS 12 sensor probes.

The Conductivity, water content and soil temperature sensor probe (Decagon 5TE) can measure volumetric water content, electrical conductivity, and temperature of soil. The sensor uses an oscillator running at 70 MHz to measure the dielectric permittivity of soil to determine the water content (VWC). A thermistor in thermal contact with the sensor prongs provides the soil temperature, while the screws on the surface of the sensor form a two-sensor electrical array to measure electrical conductivity.

Figure: Conductivity, water content and soil temperature 5TE sensor probe (Decagon 5TE)

Specifications

General specifications

• Operating temperature: -40 to 60 ºC

• Dielectric measurement frequency: 70 MHz

• Measurement time: 150 ms

• Dimensions: 10 cm x 3.2 cm x 0.7 cm

• Prong length: 5.2 cm

• Cable length: 5 m

Volumetric water content

• Range: Apparent dielectric permittivity (εa): 1 (air) to 80 (water)

• Resolution:

  • 0.1 εa (unitless) from 1 to 20,

  • < 0.75 εa (unitless) from 20 to 80

  • 0.0008 m³/ m³ (0.08% VWC) from 0 to 50% VWC

• Accuracy: εa : ±1 εa (unitless) from 1 to 40 (soil range), ±15% from 40 to 80 (VWC)

Bulk electrical conductivity

• Range: 0 to 23 dS/m (bulk)

• Resolution: 0.01 dS/m from 0 to 7 dS/m, 0.05 dS/m from 7 to 23 dS/m

• Accuracy: ±10% from 0 to 7 dS/m

Temperature

• Range: −40 to 60 ºC

• Resolution: 0.1 ºC

• Accuracy: ±1 ºC

Measurement process

The 5TE sensor provides a digital signal using the SDI-12 protocol.

Reading code:

{
    // 1. Declare an object for the sensor
    Decagon_5TE mySensor(XTR_SOCKET_A);

    // 2. Turn ON the sensor
    mySensor.ON();

    // 3. Read the sensor. Values stored in class variables
    // Check complete code example for details
    mySensor.read();

    // 4. Turn off the sensor
    mySensor.OFF();
}

Volumetric water content (VWC) calculation

The 5TE sensor provides the dielectric permittivity (εa) of the surrounding medium. The dielectric permittivity value must be converted in the code to a particular substrate by a calibration equation specific to the media you are working in.

The calibration equation for mineral soil (Topp equation) is:

$$VWC(m³/m³) = 4.3*10⁻⁶*εa³-5.5*10⁻⁴*εa²+2.92*10⁻²*εa-5.3*10⁻²$$

The calibration equation for potting soil is:

$$VWC(m³/m³) = 2.25*10⁻⁵*εa³-2.06*10⁻³*εa²+7.24*10⁻²*εa-0.247$$

The calibration equation for rockwool is:

$$VWC(m³/m³) = 1.68*10⁻³*εa²+6.56*10⁻²*εa+0.0266$$

The calibration equation for perlite is:

$$VWC(m³/m³) = -1.07*10⁻³*εa²+5.25*10⁻²*εa-0.0685$$

You can find a complete example code for reading this sensor probe and for calculating VWC for mineral soil in the following link: https://development.libelium.com/ag-xtr-08-5te-sensor-reading/

Socket

Connect the 5TE sensor probe to Plug & Sense! Smart Agriculture Xtreme in any of the sockets shown in the image below.

Figure: Available sockets for the 5TE sensor probe

Installation

The 5TE sensor can be inserted into growing media or soil, and it needs to be completely covered by soil.

It is important to avoid air gaps or extremely compact soil around the sensor. Do not install the 5TE sensor next to large metal objects, which can attenuate the sensor electromagnetic field and distort output readings.

Figure: Water content, electrical conductivity, and temperature sensor installation

You can find the complete sensor manual on the manufacturer's website.

Application examples

• Greenhouse substrate monitoring

• Irrigation management

• Salt management

• Fertilizer movement

• Modeling processes that are affected by temperature

Quality Assurance Certificate

Together with this sensor we provide a quality assurance certificate in which the manufacturer ensures that the sensor has passed the internal quality procedures.

Soil temperature and volumetric water content sensor probe (Decagon 5TM)

This sensor probe was discontinued by Libelium in July 2020 since it was discontinued by its manufacturer. From that moment, our customers can choose the equivalent TEROS 11 and TEROS 12 sensor probes.

The Soil temperature and volumetric water content sensor probe (Decagon 5TM) sensor can measure volumetric water content and temperature of soil. The sensor uses an oscillator running at 70 MHz to measure the dielectric permittivity of soil to determine the water content (VWC). A thermistor in thermal contact with the sensor prongs provides the soil temperature.

Figure: Soil temperature and volumetric water content sensor probe (Decagon 5TM)

Specifications

General specifications

• Operating temperature: -40 to 60 ºC

• Dielectric measurement frequency: 70 MHz

• Measurement time: 150 ms

• Dimensions: 10 cm x 3.2 cm x 0.7 cm

• Prong length: 5.2 cm

• Cable length: 5 m

Volumetric water content

• Range: Apparent dielectric permittivity (εa): 1 (air) to 80 (water)

• Resolution:

  • 0.1 εa (unitless) from 1 to 20,

  • < 0.75 εa (unitless) from 20 to 80

  • 0.0008 m³/ m³ (0.08% VWC) from 0 to 50% VWC

• Accuracy: εa : ±1 εa (unitless) from 1 to 40 (soil range), ±15% from 40 to 80 (VWC)

Temperature

• Range: −40 to 60 ºC

• Resolution: 0.1 ºC

• Accuracy: ±1 ºC

Measurement process

The 5TM sensor provides a digital signal using the SDI-12 protocol.

Reading code:

{
    // 1. Declare an object for the sensor
    Decagon_5TM mySensor(XTR_SOCKET_A);

    // 2. Turn ON the sensor
    mySensor.ON();

    // 3. Read the sensor. Values stored in class variables
    // Check complete code example for details
    mySensor.read();

    // 4. Turn off the sensor
    mySensor.OFF();
}

Volumetric water content (VWC) calculation

The 5TM sensor provides the dielectric permittivity (εa) of the surrounding medium. The dielectric permittivity value must be converted in your code to your particular substrate volumetric water content by a calibration equation specific to the media you are working in.

The calibration equation for mineral soil (Topp equation) is:

$$VWC(m³/m³) = 4.3*10⁻⁶*εa³-5.5*10⁻⁴*εa²+2.92*10⁻²*εa-5.3*10⁻²$$

The calibration equation for potting soil is:

$$VWC(m³/m³) = 2.25*10⁻⁵*εa³-2.06*10⁻³*εa²+7.24*10⁻²*εa-0.247$$

The calibration equation for rockwool is:

$$VWC(m³/m³) = 1.68*10⁻³*εa²+6.56*10⁻²*εa+0.0266$$

The calibration equation for perlite is:

$$VWC(m³/m³) = -1.07*10⁻³*εa²+5.25*10⁻²*εa-0.0685$$

You can find a complete example code for reading this sensor probe and calculating VWC for mineral soil in the following link: https://development.libelium.com/ag-xtr-09-5tm-sensor-reading/

Socket

Connect the 5TM sensor probe to Plug & Sense! Smart Agriculture Xtreme in any of the sockets shown in the image below.

Figure: Available sockets for the 5TM sensor probe

Installation

The 5TM sensor can be inserted into growing media or soil, and it needs to be completely covered by soil.

It is important to avoid air gaps or extremely compact soil around the sensor. Do not install the 5TM sensor next to large metal objects, which can attenuate the sensor electromagnetic field and distort output readings.

Figure: 5TE sensor installation

You can find the complete sensor manual on the manufacturer's website.

Application examples

• Soil water balance

• Irrigation management

• Modeling processes that are affected by temperature

Quality Assurance Certificate

Together with this sensor we provide a quality assurance certificate in which the manufacturer ensures that the sensor has passed the internal quality procedures.

Soil water potential sensor probe (Meter TEROS 21)

There are 2 basic parameters that describe the state of water in soil: one is soil water content, or the amount of water per unit of soil, and the other is soil water potential, or the energy state of water in the soil. Although water content is useful when trying to describe the water balance of a soil, i.e. how much water is moving in, out, or being stored, water potential is often preferred over water content because it determines how water moves in a soil or from the soil to the plant. In addition, you can use water potential to determine plant availability of water, schedule irrigation, or determine the mechanical stress state of soil.

The Soil water potential sensor probe (Meter TEROS 21) measures the water potential and temperature of a wide range of soil and other porous materials without user maintenance and factory calibration. Its extended range makes this sensor ideal for measuring the water potential in natural systems or other drier systems. The added temperature measurements can be used to determine approximate soil water potential in frozen soils.

Figure: Soil water potential sensor probe (Meter TEROS 21)

The Meter TEROS 21 sensor was previously named as Decagon MPS-6

Specifications

General specifications

• Operating temperature: -40 to 60 ºC (no water potential measurement below 0 ºC)

• Operation humidity: 0 ~ 100% RH

• Dielectric measurement frequency: 70 MHz

• Measurement time: 150 ms

• Dimensions: 9.6 cm (L) x 3.5 cm (W) x 1.5 cm (D)

• Sensor diameter: 3.2 cm

• Cable length: 5 m

Water potential

• Range: -9 to -2000 kPa*

• Resolution: 0.1 kPa

• Accuracy: ±(10% of reading + 2 kPa) from −9 to −100 kPa

Temperature

• Range: −40 to 60 ºC

• Resolution: 0.1 ºC

• Accuracy: ±1 ºC

*Note: TEROS 21 sensors with serial numbers up to T21-00009999 have a water potential range of −9 to −100,000 kPa.

Measurement process

The TEROS 21 sensor provides a digital signal using the SDI-12 protocol.

Reading code:

{
    // 1. Declare an object for the sensor
    TEROS_21 mySensor(XTR_SOCKET_A);

    // 2. Turn ON the sensor
    mySensor.ON();

    // 3. Read the sensor. Values stored in class variables
    // Check complete code example for details
    mySensor.read();

    // 4. Turn off the sensor
    mySensor.OFF();
}

You can find a complete example code for reading this sensor probe in the following link: https://development.libelium.com/ag-xtr-10-mps6-sensor-reading/

Socket

Connect the TEROS21 sensor probe to Plug & Sense! Smart Agriculture Xtreme in any of the sockets shown in the image below.

Figure: Available sockets for the TEROS 21 sensor probe

Installation

The TEROS21 sensor needs good hydraulic contact with the surrounding soil. The best method for installing the sensor is to take some native soil, wet it, and pack it in a ball around the entire sensor, making sure that the moist soil is in contact with all surfaces of the ceramic in the sensor. Then place the sensor into the soil at the desired depth.

After installing the sensor, the hole that was excavated to bury the sensor at depth should be back-filled with care taken to pack the soil back to its native bulk density. Leave at least 15 centimeters of sensor cable beneath the soil before bringing the cable to the surface.

Figure: TEROS21 sensor installation

You can find the complete sensor manual on the manufacturer's website.

Application examples

• Deficit irrigation monitoring and control

• Water potential monitoring in the vadose zone

• Crop stress

• Waste water drainage studies

• Plant water availability

Quality Assurance Certificate

Together with this sensor we provide a quality assurance certificate in which the manufacturer ensures that the sensor has passed the internal quality procedures.

(Meter ATMOS 14) Vapor pressure, humidity, temperature and air pressure sensor probe

The ATMOS 14 sensor probe is an accurate tool to measure air temperature, relative humidity (RH), vapor pressure and barometric pressure in the air. A microprocessor within the sensor calculates vapor pressure from the RH and temperature measurements. The sensor uses a sensor chip to measure both air temperature and RH and a secondary chip to measure barometric pressure.

Until June 2021, this sensor was distributed by Libelium with the name "Vapor pressure, humidity, temperature and pressure in soil and air sensor probe (Decagon VP-4)".

Meter is the new corporate name for Decagon. The manufacturer calls it ATMOS 14 now, and makes no reference to measuring in the soil, so it is only valir for air measurements.

Besides, this ATMOS 14 corresponds to Generation 2 (Gen 2). This new version features finer accuracies, smaller time drifts and shorter aquilibration times.

For the former VP-4: Despite this sensor can be installed in dry soils with a good performance, it is not recommended for saturated soils. The humidity measurements could saturate and could give a drift. Moreover, if the soil is completely saturated, it will not make sense to measure barometric pressure because there will not be air in the soil.

Figure: Vapor pressure, humidity, temperature and air pressure sensor probe (VP4)

Figure: ATMOS 14 sensor inside radiation shield

Specifications

General specifications

• Operating temperature: −40 to 80 ºC

• Measurement time: 50 ms

• Dimensions

  • 2.0 cm (0.8 in)

  • 5.4 cm (2.1 in)

• Cable length: 5 m

Vapor pressure

• Range: 0 to 47 kPa

• Resolution: 0.01 kPa

• Accuracy: see diagram below

Vapor pressure sensor accuracy

Temperature

• Range: −40 to 80 ºC

• Resolution: 0.1 ºC

• Equilibration time: <165 s (response time in 1 m/s air stream)

• Long term drift: < 0.03 ºC/year typical

• Accuracy: ±0.2 °C

Barometric pressure

• Range: 1 to 120 kPa

• Resolution: 0.01 kPa

• Accuracy: ±0.05 kPa at 25 °C

• Equilibration Time (τ, 63%) <10 ms

• Long-Term Drift <0.1 kPa/year, typical

Relative humidity

• Range: 0 to 100% RH

• Resolution: 0.1% RH

• Equilibration time: < 25 s (response time in 1 m/s air stream)

• Hysteresis: <0.80% RH typical

• Long term drift: <0.25% RH/year typical

• Accuracy: see diagram below

RH sensor accuracy

Measurement process

The ATMOS 14 provides a digital signal using the SDI-12 protocol.

Reading code:

{
    // 1. Declare an object for the sensor
    ATMOS_14 mySensor(XTR_SOCKET_A);

    // 2. Turn ON the sensor
    mySensor.ON();

    // 3. Read the sensor. Values stored in class variables
    // Check complete code example for details
    mySensor.read();

    // 4. Turn off the sensor
    mySensor.OFF();
}

You can find a complete example code for reading this sensor probe in the following link: https://development.libelium.com/ag-xtr-11-atmos-14-sensor-reading/

Socket

Connect the ATMOS 14 sensor probe to Plug & Sense! Smart Agriculture Xtreme in any of the sockets shown in the image below.

Figure: Available sockets for the ATMOS 14 sensor probe

Installation

The humidity sensor needs to be at air temperature in order to get accurate representation of the atmospheric humidity, for this reason in most outdoor uses it is necessary to house the sensor inside a radiation shield with adequate air flow. This allows the sensor to be in equilibrium with air temperature. The radiation shield comes with a mounting bracket and 7 discs that prevent direct sunlight from coming into contact with the sensor.

Figure: Inserting the ATMOS 14 sensor in the radiation shield

The radiation shield with the sensor can be mounted on the desired place. Fasten the sensor cord to the mounting post to avoid that the weight of the cable pulls out the sensor.

Figure: The ATMOS 14 sensor installation

You can find the complete sensor manual on the manufacturer's website.

Application examples

• Greenhouse and canopy monitoring

• Reference evapotranspiration calculations

• Routine weather monitoring

• Building humidity monitoring

• Mold remediation

• Modeling processes that are affected by vapor pressure or humidity

Quality Assurance Certificate

Together with this sensor we provide a quality assurance certificate in which the manufacturer ensures that the sensor has passed the internal quality procedures.

(Decagon VP-4) Vapor pressure, humidity, temperature and pressure in soil and air sensor probe

The VP-4 sensor probe is an accurate tool to measure air temperature, relative humidity (RH), vapor pressure, and barometric pressure in soil and in air. A microprocessor within the sensor calculates vapor pressure from the RH and temperature measurements. The sensor uses a sensor chip to measure both air temperature and RH and a secondary chip to measure barometric pressure.

Despite this sensor can be installed in dry soils with a good performance, it is not recommended for saturated soils. The humidity measurements could saturate and could give a drift. Moreover, if the soil is completely saturated, it will not make sense to measure barometric pressure because there will not be air in the soil.

Figure: Vapor pressure, humidity, temperature and pressure in soil and air sensor probe (Decagon VP-4)

Figure: VP-4 sensor inside radiation shield

Specifications

General specifications

• Operating temperature: −40 to 80 ºC

• Measurement time: 300 ms

• Dimensions: 1.96 cm (diameter) x 5.4 cm (h)

• Cable length: 5 m

Vapor pressure

• Range: 0 to 47 kPa

• Resolution: 0.001 kPa

• Accuracy: see diagram below

Figure: Vapor pressure accuracy chart

Temperature

• Range: −40 to 80 ºC

• Resolution: 0.1 ºC

• Equilibration time: < 400 s

• Long term drift: < 0.04 ºC/year typical

• Accuracy: see diagram below

Figure: Temperature accuracy chart

Barometric pressure

• Range: 49 to 109 kPa

• Resolution: 0.01 kPa

• Accuracy: 0.4 kPa

Relative humidity

• Range: 0 to 100% RH

• Resolution: 0.1% RH

• Equilibration time: <40 s

• Hysteresis: <1% RH typical

• Long term drift: <0.5% RH/year typical

• Accuracy: see diagram below

Figure: Humidity accuracy chart

Measurement process

The VP-4 sensor provides a digital signal using the SDI-12 protocol.

Reading code:

{
    // 1. Declare an object for the sensor
    Decagon_VP4 mySensor(XTR_SOCKET_A);

    // 2. Turn ON the sensor
    mySensor.ON();

    // 3. Read the sensor. Values stored in class variables
    // Check complete code example for details
    mySensor.read();

    // 4. Turn off the sensor
    mySensor.OFF();
}

You can find a complete example code for reading this sensor probe in the following link: https://development.libelium.com/ag-xtr-11-vp4-sensor-reading/

Socket

Connect the VP-4 sensor probe to Plug & Sense! Smart Agriculture Xtreme in any of the sockets shown in the image below.

Figure: Available sockets for the VP-4 sensor probe

Installation

The humidity sensor needs to be at air temperature in order to get accurate representation of the atmospheric humidity, for this reason in most outdoor uses it is necessary to house the sensor inside a radiation shield with adequate air flow. This allows the sensor to be in equilibrium with air temperature. The radiation shield comes with a mounting bracket and 7 discs that prevent direct sunlight from coming into contact with the sensor.

Figure: Inserting the VP-4 sensor in the radiation shield

The radiation shield with the sensor can be mounted on the desired place. Fasten the sensor cord to the mounting post to avoid that the weight of the cable pulls out the sensor.

Figure: The VP-4 sensor installation

You can find the complete sensor manual on the manufacturer's website.

Application examples

• Greenhouse and canopy monitoring

• Reference evapotranspiration calculations

• Routine weather monitoring

• Building humidity monitoring

• Mold remediation

• Modeling processes that are affected by vapor pressure or humidity

Quality Assurance Certificate

Together with this sensor we provide a quality assurance certificate in which the manufacturer ensures that the sensor has passed the internal quality procedures.

Leaf wetness Phytos 31 sensor probe (Decagon Phytos 31)

The Leaf wetness Phytos 31 sensor probe (Decagon Phytos 31) measures leaf surface wetness by measuring the dielectric constant of the sensor's upper surface. This sensor has very high resolution, which gives you the ability to detect very small amounts of water (or ice) on the sensor surface. Water on the sensor surface does not need to bridge electrical traces to be detected, as is common with resistance-based surface wetness sensors.

Figure: Leaf wetness Phytos 31 sensor probe (Decagon Phytos-31)

Specifications

• Operating temperature: -20 to 60 ºC

• Measurement time: 10 ms

• Probe dimensions: 11.2 cm x 5.8 cm x 0.075 cm

• Cable length: 5 m

Measurement process

The Phytos 31 sensor probe provides an analog signal.

Reading code:

{
    // 1. Declare an object for the sensor
    leafWetness mySensor();

    // 2. Turn ON the sensor
    mySensor.ON();

    // 3. Read the sensor. Values stored in class variables
    // Check complete code example for details
    mySensor.read();

    // 4. Turn off the sensor
    mySensor.OFF();
}

You can find a complete example code for reading this sensor probe in the following link: https://development.libelium.com/ag-xtr-12-phytos-sensor-reading/

Socket

Connect the Phytos 31 sensor probe to Plug & Sense! Smart Agriculture Xtreme in any of the sockets shown in the image below.

Figure: Available sockets for the Phytos 31 sensor probe

Installation

The Leaf wetness sensor is designed with leaf shape in order to be mounted next to the canopy or on a weather station pole. The 2 holes in the black part of the sensor can be used to fix the sensor with bolts or zip ties. Unlike other leaf wetness sensors, this sensor does not require to be installed at a specific inclination (45º, for example). Besides, the plastic surface of this sensor makes it more resistant to oxidation than traditional leaf wetness sensors with exposed electric traces.

Figure: Phytos 31 sensor installation

You can find the complete sensor manual on the manufacturer's website.

Application examples

• Decision of usage for crop fungicides

• Predict crop diseases or infections

Quality Assurance Certificate

Together with this sensor we provide a quality assurance certificate in which the manufacturer ensures that the sensor has passed the internal quality procedures.

Dendrometer sensor probes for Smart Agriculture Xtreme (Ecomatik DC3, DD-S and DF4)

Dendrometers are highly precise instruments for the continuous measurement of changes in plant diameter (i.e. growth dynamic, diurnal diameter changes). Dendrometer signals document the response of plants to their environment in high temporal resolution.

This type of sensors do not measure the total diameter of the trunk or fruit, but the micro variations in diameter. That is a great tool to study how well the plant grows, absorbs and transpires water, its hydrological stress, possible diseases, etc.

Figure: Dendrometer sensor (Ecomatik DF)

Ecomatik DC3 specifications (Trunk diameter)

• Operation temperature: -30 ~ 40 ºC

• Operation humidity: 0 ~ 100% RH

• Trunk/branch diameter: from 5 cm

• Accuracy: ±3.3 μm

• Temperature coefficient: <1.4 μm/K

• Linearity: 0.7%

• Output range: 0 ~ 20 kΩ

• Range of the sensor: function of the size of the tree:

Tree Diameter (cm)	Measuring range in diameter (mm)
10	16.2
50	11.3
100	9.0

Note: The previous version of the DC3 Trunk diameter (the DC2) has been discontinued, but it is still available for replacements on demand. Contact your Sales agent for more information.

Ecomatik DD-S specifications (Stem diameter)

• Operation temperature: -30 ~ 40 ºC

• Operation humidity: 0 ~ 100% RH

• Stem/branch diameter: 0 ~ 20 cm

• Range of the sensor: 11 mm

• Output range: 0 ~ 20 kΩ

• Accuracy: ±2 μm

• Temperature coefficient: <0.1μm/K

• Cable length: 2 m

Ecomatik DF4 specifications (Fruit diameter)

Specifications

Fruit diameter: ~ 13 cm Range of the sensor: 120 mm Output range: 0 ~ 20 kΩ Accuracy: ±4.4 μm Temperature coefficient: <0.2 μm/K Operation temperature: -30 ~ 70 ºC Operation humidity: 0 ~ 100% RH Cable length: 5 m

​The sensor is protected from rainwater, but it is not sealed. Please do not immerse the sensor in water. Max. fruit diameter 135 mm, exceedance may cause sensor damage

Installation process of DF4

a) Select a representative fruit for instrumentation.

b) Use the included rubber cord to strain relief the sensor by fixing the sensor cable on the fruit carrying branch. Please leave enough cable between the fixation point on the branch and the sensor. In the final installation position, the fruit sensor should be able to move freely with the instrumented fruit, without tension on the cable.

c) Pull apart the sensor clamping system and carefully insert the fruit into the fruit gripper. Make sure that the sensor is attached firmly to the fruit and that the fruit grippers are in firm contact to the fruit surface.

d) Fix the cable onto the stem or on a ground stake for strain relief of the sensor cable between instrumented plant and the data logger. This can be done using a rope or cable straps. There should be no tension between the sensor, fixation point at the fruit carrying branch and the remaining sensor cable.

!! IMPORTANT !! Fix the cable onto the tree stem/branch so that the sensor is protected from any accidental pull/ drag of the entire cable length. This can be done using a rope or cable straps. In addition, there should be no tension between the sensor and cable. Ensure that no rainwater can run along the cable, or the sensor rod and enter the sensor casing. Rod entrance, as well as wire outlet, should hence always be inclined downwards.

Measurement process

The operation of the 3 Ecomatik dendrometers, DC3, DD-S and DF, is based on the variation of an internal resistance with the pressure that the growing of the trunk, stem, branch or fruit exerts on the sensor. The Ecomatik dendrometers provide an analog output signal.

Reading code:

{
    // 1. Declare an object for the sensor
    dendrometer mySensor(DENDRO_DD);

    // 2. Turn ON the sensor
    mySensor.ON();

    // 3. Read the sensor. Values stored in class variables
    // Check complete code example for details
    mySensor.read();

    // 4. Turn off the sensor
    mySensor.OFF();
}

You can find a complete example code for reading this sensor probe in the following link: https://development.libelium.com/ag-xtr-13-dendrometer-sensor-reading/

Socket

Connect the Ecomatik dendrometer sensor probe to Plug & Sense! Smart Agriculture Xtreme in any of the sockets shown in the image below.

Note: This sensor has a specific wiring for the Plug & Sense! Smart Agriculture Xtreme model, so it is not compatible with other Plug & Sense! models and vice versa. Refer to our Sales department for more information.

Figure: Available sockets for Ecomatik dendrometers sensor probes

Installation

There are 3 different dendrometer models focused on different elements to be measured. Place the sensor as you can see in the following images.

Figure: Ecomatik DC3 sensor for trunk diameter

Figure: Ecomatik DD-S sensor for stem diameter

Figure: Ecomatik DF sensor for fruit diameter

Application examples

• Monitoring of growth processes of plants

• Examination of the influence of environmental factors on plant growth

• Precise dating of beginning and end of the growing season

Weather station sensor probes (Gill Instruments MaxiMet series)

The Plug & Sense! Smart Agriculture Xtreme model offers the possibility of connecting any of the MaxiMet weather stations provided by Gill Instruments.

In February 2021, the manufacturer Gill reports their optical precipitation sensor is valid for knowing if it rains. Compact and with low maintenance, it gives a general idea of the amount of rain, but it is not really accurate. Choose the Tipping Bucket for superior accuracy and reliability.

As a result, Libelium discontinued all the Gill sensor probes and accessories with the exception of 3 weather stations: GMX-240 (W-PO), GMX-550 (W-x-T-H-AP) and GMX-551 (W-x-T-H-AP-R). Besides, an accurate rain sensor is available for GMX-550 and GMX-551: Tipping Bucket Accessory for GMX Weather Stations.

The MaxiMet series offers a compact solution for weather forecast. The user can choose easily the best configuration thanks to the modularity that they offer, keeping the robustness, easy installation and low maintenance features. In other words, any of the different weather sensors can be combined in a custom model.

Parameters related with wind, precipitation, solar radiation, dew point, air temperature, air humidity or atmospheric air pressure can be measured with these weather station probes.

In the next subsections, all the available models are described briefly to allow the user selecting the best for each application. However, a feature table is also provided below:

Weather station	Wind and compass	Precipitation	Temperature, relative humidity and pressure	Solar radiation	GPS
GMX-100 (PO)		X (Optical)
GMX-101 (R)				X
GMX-200 (W)	X				Optional
GMX-240 (PO-W)	X	X (Optical)			Optional
GMX-300 (T-H-AP)			X
GMX-301 (T-H-AP-R)			X	X
GMX-400 (PO-T-H-AP)		X (Optical)	X
GMX-500 (W-T-H-AP)	X		X		Optional
GMX-501 (W-T-H-AP-R)	X		X	X	Optional
GMX-531 (W-PT-T-H-AP-R)	X	X (Tipping bucket)	X	X	Optional
GMX-541 (W-PO-T-H-AP-R)	X	X (Optical)	X	X	Optional
GMX-550 (W-x-T-H-AP)	X	Optional (Tipping bucket)	X		Optional
GMX-551 (W-x-T-H-AP-R)	X	Optional (Tipping bucket)	X	X	Optional
GMX-600 (W-PO-T-H-AP)	X	X (Optical)	X		Optional

According to Libelium's nomenclature:

• PO: Includes a Precipitation sensor (Optical type)

• PT: Includes a Precipitation sensor (Tipping bucket type)

• x: This item accepts a Precipitation sensor (tipping bucket type), needs to be ordered apart

• W: Includes a Wind sensor

• T-H-AP: Includes air Temperature, air Humidity and Atmospheric air Pressure sensors

• R: Includes a Radiation sensor

As seen, the weather stations capable of metering wind, can accept a GPS accessory (available on demand, needs to be ordered specially).

The precipitation parameter can be measured with 2 different sensors: the optical one and the traditional tipping bucket (Gill's Kalyx rain gauge). The tipping bucket is more accurate then the optical sensor. The tipping bucket needs to be ordered as an accessory for the GMX-550 and GMX-551 (available on demand).

MaxiMet GMX-100 (PO) sensor probe

The MaxiMet GMX-100 sensor probe provides information about precipitation (optical method).

An integrated optical rain gauge that senses water hitting its outside surface provides measurements based on the size and number of drops.

The optical rain gauge has no moving parts so possible mechanical problems are avoided.

Figure: MaxiMet GMX-100 sensor probe

MaxiMet GMX-101 (R) sensor probe

The MaxiMet GMX-101 sensor probe provides accurate information about solar radiation.

An integrated pyranometer, protected by a single glass, measures the solar radiation. In addition, an inclinometer is also included to allow a precise installation.

Figure: MaxiMet GMX-101 sensor probe

MaxiMet GMX-200 (W) sensor probe

The MaxiMet GMX-200 sensor probe provides accurate information about wind.

Three ultrasonic sensors provide wind speed and direction measurements and the addition of an electronic compass provides apparent wind measurement. Average speed and direction together with WMO averages and gust data are also provided.

In addition, this model has a compass and an optional GPS.

Figure: MaxiMet GMX-200 sensor probe

MaxiMet GMX-240 (W-PO) sensor probe

The MaxiMet GMX-240 is a weather station that provides accurate meteorological information about wind and precipitation (optical method).

Three ultrasonic sensors provide wind speed and direction measurements and the addition of an electronic compass provides apparent wind measurement. Average speed and direction together with WMO averages and gust data are also provided.

An integrated optical rain gauge that senses water hitting its outside surface provides measurements based on the size and number of drops.

The optical rain gauge and the wind ultrasonic sensors have no moving parts so possible mechanical problems are avoided.

Figure: MaxiMet GMX-240 sensor probe

MaxiMet GMX-300 (T-H-AP) sensor probe

The MaxiMet GMX-300 sensor probe provides accurate information about air temperature, air humidity and atmospheric air pressure.

This model is basically a solar shield with no moving parts which allows high performance over large time periods.

Figure: MaxiMet GMX-300 sensor probe

MaxiMet GMX-301 (T-H-AP-R) sensor probe

The MaxiMet GMX-301 sensor probe provides accurate information about air temperature, air humidity, atmospheric air pressure and solar radiation.

This model is basically a solar shield with no moving parts which allows high performance over large time periods. On the top of the solar shield, an integrated pyranometer protected by a single glass measures the solar radiation. In addition, an inclinometer is also included to allow a precise installation.

Figure: MaxiMet GMX-301 sensor probe

MaxiMet GMX-400 (PO-T-H-AP) sensor probe

The MaxiMet GMX-400 sensor probe provides information about precipitation (optical method), air temperature, air humidity and atmospheric air pressure.

This model is basically a solar shield with no moving parts which allows high performance over large time periods. On the top of the solar shield, an integrated optical rain gauge senses water hitting its outside surface, providing measurements based on the size and number of drops.

Figure: MaxiMet GMX-400 sensor probe

MaxiMet GMX-500 (W-T-H-AP) sensor probe

The MaxiMet GMX-500 sensor probe provides accurate information about wind, air temperature, air humidity and atmospheric air pressure.

This model is basically a solar shield with no moving parts which allows high performance over large time periods. On the top of the solar shield, three ultrasonic sensors are placed to provide wind speed and direction measurements. Besides, an electronic compass provides apparent wind measurement. Average speed and direction together with WMO averages and gust data are also provided.

Figure: MaxiMet GMX-500 sensor probe

MaxiMet GMX-501 (W-T-H-AP-R) sensor probe

The MaxiMet GMX-501 sensor probe provides accurate information about wind, air temperature, air humidity, atmospheric air pressure and solar radiation.

This model is basically a solar shield with no moving parts which allows high performance over large time periods. On the top of the solar shield, three ultrasonic sensors are placed to provide wind speed and direction measurements. Besides, an electronic compass provides apparent wind measurement. Average speed and direction together with WMO averages and gust data are also provided. Additionally, an integrated pyranometer protected by a single glass measures the solar radiation. Finally, an inclinometer is also included to allow a precise installation.

Figure: MaxiMet GMX-501 sensor probe

MaxiMet GMX-531 (W-PT-T-H-AP-R) sensor probe

The MaxiMet GMX-531 sensor probe provides accurate information about wind, precipitation (tipping bucket method), air temperature, air humidity, atmospheric air pressure and solar radiation.

This model is basically a solar shield with no moving parts which allows high performance over large time periods. On the top of the solar shield, three ultrasonic sensors are placed to provide wind speed and direction measurements. Besides, an electronic compass provides apparent wind measurement. Average speed and direction together with WMO averages and gust data are also provided. Additionally, an integrated pyranometer protected by a single glass measures the solar radiation. Finally, an inclinometer is also included to allow a precise installation.

On top of that, a tipping bucket rain gauge is provided to measure precipitation, with excellent performance in tropical or heavy precipitation locations. The Kalyx rain gauge is connected using a 20 m cable.

Figure: MaxiMet GMX-531 sensor probe

MaxiMet GMX-541 (W-PO-T-H-AP-R) sensor probe

The MaxiMet GMX-541 sensor probe provides information about wind, precipitation (optical method), air temperature, air humidity, atmospheric air pressure and solar radiation.

This model is basically a solar shield with no moving parts which allows high performance over large time periods. On the top of the solar shield, three ultrasonic sensors are placed to provide wind speed and direction measurements. Besides, an electronic compass provides apparent wind measurement. Average speed and direction together with WMO averages and gust data are also provided. Additionally, an integrated pyranometer protected by a single glass measures the solar radiation. Finally, an inclinometer is also included to allow a precise installation.

On top of that, an optical gauge is provided to measure precipitation. It senses water hitting its outside surface, providing measurements based on the size and number of drops. The optical rain gauge is connected using a 20 m cable.

Figure: MaxiMet GMX-541 sensor probe

MaxiMet GMX-550 (W-x-T-H-AP) sensor probe

The MaxiMet GMX-550 sensor probe provides accurate information about wind, precipitation (with an accessory), air temperature, air humidity and atmospheric air pressure.

This model is basically a solar shield with no moving parts which allows high performance over large time periods. On the top of the solar shield, three ultrasonic sensors are placed to provide wind speed and direction measurements. Besides, an electronic compass provides apparent wind measurement. Average speed and direction together with WMO averages and gust data are also provided. Finally, an inclinometer is also included to allow a precise installation.

On top of that, an integrated connector allows the user to connect a tipping bucket rain gauge to measure precipitation.

Figure: MaxiMet GMX-550 sensor probe

MaxiMet GMX-551 (W-x-T-H-AP-R) sensor probe

The MaxiMet GMX-551 sensor probe provides accurate information about wind, precipitation (with an accessory), air temperature, air humidity, atmospheric air pressure and solar radiation.

This model is basically a solar shield with no moving parts which allows high performance over large time periods. On the top of the solar shield, three ultrasonic sensors are placed to provide wind speed and direction measurements. Besides, an electronic compass provides apparent wind measurement. Average speed and direction together with WMO averages and gust data are also provided. Additionally, an integrated pyranometer protected by a single glass measures the solar radiation. Finally, an inclinometer is also included to allow a precise installation.

On top of that, an integrated connector allows the user to connect a tipping bucket rain gauge to measure precipitation.

Figure: MaxiMet GMX-551 sensor probe

MaxiMet GMX-600 (W-PO-T-H-AP) sensor probe

The MaxiMet GMX-600 sensor probe provides information about wind, precipitation (optical method), air temperature, air humidity and atmospheric air pressure.

This model is basically a solar shield with no moving parts which allows high performance over large time periods. On the top of the solar shield, three ultrasonic sensors are placed to provide wind speed and direction measurements. Besides, an electronic compass provides apparent wind measurement. Average speed and direction together with WMO averages and gust data are also provided. Moreover, an integrated optical rain gauge senses water hitting its outside surface, providing measurements based on the size and number of drops. Finally, an inclinometer is also included to allow a precise installation.

Figure: MaxiMet GMX-600 sensor probe

Specifications for each weather station sensor

General specifications

• Operating temperature: -40 to 70 ºC

• Operation humidity: 0 ~ 100% RH

• Weight (approximate, depends on models): 0.5 kg

• Dimensions (approximate, depends on models): 141 x 209.5 mm

• Cable length: 1.5 m

• Protection Class: IP66

Wind speed

• Range: 0.01 m/s to 60 m/s

• Accuracy: ±3% to 40 m/s; ±5% above 40 and up to 60 m/s

• Resolution: 0.01 m/s

• Threshold: 0.01 m/s

Wind direction

• Range: 0-359º

• Accuracy: ±3º to 40 m/s; ±5º above 40 and up to 60 m/s

• Resolution: 1º

• Starting threshold: 0.05 m/s

Compass

• Range: 0-359º

• Accuracy: ±3º

• Resolution: 1º

Precipitation: optical method

• Range: 0 to 300 mm/h

• Precipitation resolution: 0.2 mm

• Repeatability: 3%

Precipitation: mechanical, tipping bucket method (Kalyx rain gauge)

• Range: 0-1000 mm/hr

• Precipitation resolution: 0.2 mm

• Accuracy: 2%

• Cable length: 20 m

Air temperature and dew point

• Range: -40 °C to +70 °C

• Resolution: 0.1 °C

• Accuracy: ± 0.3 °C @ 20 °C

Air humidity

• Range: 0 - 100%

• Resolution: 1%

• Accuracy: ± 2% @ 20 °C (10%-90% RH)

Atmospheric air pressure

• Range: 300 to 1100 hPa

• Resolution: 0.1 hPa

• Accuracy: ± 0.5 hPa @ 25 °C

Global solar radiation

• Wavelength sensitivity: 300 to 3000 nm

• Range: 0 to 1600 W/m²

• Resolution: 1 W/m²

• DIN standard: ISO 9060 Second Class

Measurement process

The MaxiMet weather stations provide a digital signal using the RS-485 protocol. The same code can be used to read all models. Nevertheless, the obtained parameters will be different.

Reading code:

{
    // 1. Declare an object for the sensor
    weatherStation mySensor;

    // 2. Turn ON the sensor
    mySensor.ON();
}

// main loop
{
    // 3. Read the sensor. Values stored in class variables
    // Check complete code example for details
    mySensor.read();

    //(...)
}

You can find a complete example code for reading this sensor probe in the following link: https://development.libelium.com/ag-xtr-15-weather-station-sensor-reading/

Socket

Connect the weather station sensor probe to Plug & Sense! Smart Agriculture Xtreme in the socket shown in the image below.

Figure: Available sockets for the weather station sensors probes

Installation

First, it is necessary to connect the cable in the bottom connector of the weather station.

Figure: Weather station bottom connector detail

Figure: Weather station cable connection

To make this connection correctly, it is necessary to insert the connector following the notches shown in the following image.

Figure: Weather station notches detail

It includes bolt fittings for securing the unit to a vertical pipe. Use a support tube of diameter 44.45 mm, 3 mm of wall thickness and 3 equidistant M5 holes.

Figure: Aproximated weather station dimensions for GMX-240

It is recommendable to use a mast for the weather station installation. The optical rain gauge on the top must be facing the sky to measure precipitation correctly. Fix the weather station to the mast with 3 M5 bolts and nuts.

Figure: Weather station installation on a pole

Figure: Weather station fixed in a pole

For the correct measurement of the wind direction it is necessary to install the weather station correctly aligned. In order to do this, check that the north alignment pointers are correctly oriented to the north. Besides, select the location trying to maximize the natural wind flow through the sensor. Wind sensors should not be installed next to any obstacles like buildings, walls, plants, enclosures or objects that might affect the air flow.

Figure: Weather station north alignment

Libelium also offers as on option the GMX Weather Station Mounting Bracket. This accessory allows a solid fastening to both wall or pole. It is not mandatory, but recommended for professional installations.

Figure: GMX Weather Station Mounting Bracket, general view

Built with anodized aluminium to reduce corrosion, it has high resistance to wind and vibration. It comes with stainless steel bolts, multiple earth points and a wall/pole mounting kit.

Figure: Dimensions of the GMX Weather Station Mounting Bracket

Finally, the weather station requires continuous measures to obtain certain average values, so the energy consumption of this sensor may be considerable depending the application. That is specially true to weather stations which measure fast-changing parameters, like wind or precipitation. Because of that, it is recommended to add external power to some Plug & Sense! Smart Agriculture Xtreme models with a weather station.

When the weather station is powered, it automatically senses weather parameters, saving their values into its internal memory and calculating average values. In order to provide average parameters such as precipitation per hour, etc, the weather station must remain powered.

However, this mode of use is not mandatory. For applications where it is not possible to add external power to the Plug & Sense! Smart Agriculture Xtreme, it is possible to turn the station on and off at specific periods of time and therefore receive punctual values of wind and rain. That is, it would not be possible to obtain every "average" calculated values nor "Precipitation total".

The energy consumption of the node will be determined by the measures needed for the application, so long term tests are recommended to see complete energy cycles.

You can find the complete sensor manual on the manufacturer's website.

Application examples

• Weather observation and forecast

• Evapotranspiration analysis

• Forest fires development forecast

Product test report

Together with this sensor we provide a product test report in which the manufacturer ensures that the sensor has passed the internal quality procedures.

Solar radiation and temperature Datasol MET probe (Atersa Datasol MET)

The Datasol MET is a precision device that allows to visualize and acquire solar radiation, peak sun hours (PSH), temperature of the cell and the ambient temperature. The radiation measurement of the Datasol MET incorporates compensation with the temperature of the cell. Additionally, an anemometer can be added as an accessory to obtain wind speed.

This sensor is especially focused on owners of a photovoltaic system looking for maximum performance.

Figure: Solar radiation and temperature Datasol MET probe

Specifications

General specifications

• Operating temperature: -20 to 50 ºC

• Weight: 1.2 kg

• Dimensions: 266 x 266 x 35 mm

• Protection class: IP54

• Cable length: 1.5 m

Temperature

• Range: -20 °C to +100 °C

• Accuracy: ±0.8 °C

Radiation

• Range: 0 to 1400 W/m²

• Intrinsic measurement error: ±0.2%

• CIEMAT reference standard measurement error: ±2%

• Maximum relative error: ±2.2%

Measurement process

The Datasol MET provides a digital signal using the RS-485 protocol.

Reading code:

{
    // 1. Declare an object for the sensor
    DatasolMET mySensor;

    // 2. Turn ON the sensor
    mySensor.ON();
}

// main loop
{
    // 3. Read the sensor. Values stored in class variables
    // Check complete code example for details
    mySensor.read();

    //(...)
}

You can find a complete example code for reading this sensor probe in the following link: https://development.libelium.com/ag-xtr-24-datasol-met-sensor-reading/

Socket

Connect the solar radiation and temperature Datasol MET probe to Plug & Sense! Smart Agriculture Xtreme in the socket shown in the image below.

Figure: Available socket for the solar radiation and temperature Datasol MET probe

Installation

Normally this sensor is used to verify the operation of a photovoltaic installation, so its location is very important, since it must share the shading and ambient temperature conditions of the solar panels. Fix the Datasol MET stably to the structure of these, always with the same inclination, either by fixing with the hook fixation accessory or by screwing it.

Figure: Solar radiation and temperature Datasol MET probe installation

Figure: Hook fixation for Solar radiation and temperature Datasol MET probe

Avoid fixing the sensor to structures that vibrate or that tend to lean over time. The Datasol MET has sensors and components that are extremely sensitive to shocks or falls. We recommend handling the Datasol MET with caution, especially during the installation process. Plan the wiring path in advance.

The Datasol MET is equipped with 2 temperature probes. Both are pre-installed and adjusted in the equipment, ready to be used. The temperature probe of the cell is installed on the laminate itself, inside the sealed box. The ambient temperature probe must hang freely, it comes out through a cable gland and it is enough to let it hang on the back of the Datasol MET.

The components of the Datasol MET are installed inside a sealed box with IP54 protection, located behind the calibrated cell. Keep the Datasol MET box sealed and the cable glands plugged and tightened, thus ensuring the necessary tightness in humid or dusty environments. Do not install the system near the reach of children or animals.

The Datasol MET hardly needs maintenance. Check that dirt has not accumulated on the glass of the cell and the good condition of the cables. Always prevent dirt from accumulating inside the Datasol MET box. In the case where the Datasol MET glass is dirty, it generates an alarm warning of it (mySensor.sensorDatasolMET.necessaryCleaningNotice).

If it is necessary to connect more than one RS-485 device, in addition to Datasol MET, you can use the accessory Socket splitter probe (RS-485) for Smart Agriculture Xtreme.

Figure: Socket splitter probe (RS-485) for Smart Agriculture Xtreme

It is a very simple accessory to use as you can see in the following images. It connects to socket E, just like the Datasol MET sensor.

Figure: Available socket for the socket splitter probe (RS-485) for Smart Agriculture Xtreme

It enables the connection of up to 3 RS-485 devices to Smart Agriculture Xtreme.

Figure: Solar radiation and temperature Datasol MET probe connected to Socket splitter probe (RS-485) for Smart Agriculture Xtreme

Accessory anemometer

The Datasol MET sensor optionally includes an anemometer. This sensor allows to obtain the wind speed. This is a relevant parameter for moving (sun-tracking) solar panel installations, because in the event of strong wind, the system should put the panels in horizontal protective position (offering the minimum surface to the wind). The sensor should be placed away from any obstacle that may interfere with the measurement of wind speed. It is very important to place it in a vertical position for its correct functioning.

Figure: Optional anemometer for Datasol MET sensor

Application examples

• Photovoltaic installation

Certificate of calibration

Together with this sensor we provide a calibration certificate in which the manufacturer ensures that the sensor has passed a calibration procedure with traceability to accredited CIEMAT reference standard.

Luminosity sensor probe (AMS TSL2561)

This is a light-to-digital converter that transforms light intensity into a digital signal output. This device combines one broadband photo-diode (visible plus infrared) and one infrared-responding photo-diode on a single CMOS integrated circuit capable of providing a near-photopic response over an effective 20-bit dynamic range (16-bit resolution). Two integrating ADCs convert the photo-diode currents to a digital output that represents the irradiance measured on each channel. This digital output in lux is derived using an empirical formula to approximate the human eye response.

Figure: Luminosity sensor probe (AMS TSL2561)

Specifications

• Operating temperature: -30 ºC to +80 ºC

• Dynamic range: 0.1 to 40000 Lux

• Spectral range: 300 - 1100 nm

• Usage: indoors and outdoors

Figure: Luminosity sensor graphic

Measurement process

The luminosity sensor provides a digital signal using the I2C protocol.

Reading code:

{
    // 1. Declare an object for the sensor
    luxes mySensor(XTR_SOCKET_A);

    // 2. Turn ON the sensor
    mySensor.ON();

    // 3. Read the sensor. Store parameters in local variables
    uint32_t luminosity = mySensor.getLuminosity();

    // 4. Turn off the sensor
    mySensor.OFF();
}

You can find a complete example code for reading this sensor probe in the following link: https://development.libelium.com/ag-xtr-17-tsl2561-sensor-reading/

Socket

Connect the Luminosity sensor probe to the Plug & Sense! Smart Agriculture Xtreme in any of the sockets shown in the image below.

Figure: Available sockets for the Luminosity sensor probe

Application examples

• Light presence detection for artificial lightning usage

Ultrasound sensor probe (MaxBotix MB7040)

The Ultrasound sensor probe (MaxBotix MB7040) has high acoustic power output along with real-time auto calibration for changing conditions (voltage and acoustic or electrical noise) that ensure users receive the most reliable ranging data for every reading taken in air.

Figure: Ultrasound sensor (Maxbotix MB7040)

Specifications

• Operation frequency: 42 kHz

• Maximum detection distance: 765 cm

• Usage: indoors and outdoors (IP-67)

Figure: Ultrasound sensor dimensions

Measurement process

The ultrasound sensor provides a digital signal using the I2C protocol.

Reading code:

{
    // 1. Declare an object for the sensor
    ultrasound mySensor(XTR_SOCKET_A);

    // 2. Turn ON the sensor
    mySensor.ON();

    // 3. Read the sensor. Store parameters in local variables
    uint16_t distance = mySensor.getDistance();

    // 4. Turn off the sensor
    mySensor.OFF();
}

You can find a complete example code for reading this sensor probe in the following link: https://development.libelium.com/ag-xtr-18-mb7040-sensor-reading/

Socket

Connect the Ultrasound sensor probe to the Plug & Sense! Smart Agriculture Xtreme in any of the sockets shown in the image below.

Figure: Available sockets for ultrasound sensor (Maxbotix MB7040)

Installation

The ultrasound sensor probe may be placed in different positions. The sensor can be focused directly to the point we want to measure.

Figure: ultrasound sensor (Maxbotix MB7040) installation

Application examples

• Tank level measurement

• Proximity zone detection

• People detection

• Distance measuring

• Security systems

• Motion detection

• Collision avoidance