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Outlook

1. Introduction – General characteristics of the sensor.

2. Installation – Set up of the sensor in the soil and connection to the

measurements system.

3. Measurements systems – Different available data acquisition

methods offered by Xop Física.

4. Measurements interpretation – Information provided by the sensor.

5. Contact – Location and contact information.

Humidec® is a conductivity sensor with a coin similar size.

It allows measuring soil humidity in a simple and immediate way, so you are able to supply water to the plant according to its real necessity.

It has a long lifetime, low maintenance and a very competitive price.

1. Introduction

2. Installation

In applications where measurements are performed in liquid media, it is enough to deep the sensor to get the measurement. When sensor has to be buried in the soil, you have to follow these steps:

1. Make a hole in the sand and place the sensor face up, forming between 0 and 30º with the

horizontal.

2. Add sand till cover the sensor, holding its orientation.

3. Compact the sand to ensure a right contact. 4. Irrigate abundantly to facilitate compactation.

In an orchard with drip irrigation, generally some different control points are set up, depending on the homogeneity and soil extension.

20 cm

40 cm

60 cm

sensors

In each control point it is advisable to install several sensors at different depths, placing the deepest a bit below the length of the roots.

For a proper optimization of the irrigation, humidity should oscillate between field capacity and withering point, and water should never arrive at the area where there are no roots, therefore, the deepest sensor should not detect the irrigation.

2. Installation

2. Installation

Once the sensors have been installed, they have to be connected to the measurement system. Usually it is placed holding from the trunk and it keeps completely watertight to avoid the entrance of water and dust.

3. Measurement systems

Xop Física offers four different measurement systems, according to the costumers necessities.

1. Digital station hm2:- It has up to 4 input channels.- Measures automatically each interval time selected by the user.- Memorise measurements (45 days capacity for measurements each 10 minutes) as adc dignal.- Data extraction is done by PC or PDA connection or via Bluetooth.

- Power supply is provided by battery (It lasts about two months for measurements each ten minutes).- It is completely watertight, protected from the water and the dust. - It has a switchable output to activate latch valves or rele’s.

2. Analogic Station hm1:

- It has 1 channel input.- Measures in a continuous way.- Output signal can be voltage or current (4-20 mA loop).- It has very low consume.- Can be supplied by 5 to 12 V.- It is compatible with existing control systems.

3. Measurement systems

hm1 station with 4 electronic boards, external (left) and internal (right) part. Configured to measure in current loop.

3. Measurement systems

3. hm1 hand reader:

- Used mainly to perform instantaneous measurements. - Consists on an hm1 electronic board connected to a display.- Measures only in voltage. - Power supply consist on four 1.5 V batteries.

3. Measurement systems

4. hm2 hand reader:

- Used mainly to perform instantaneous measurements.

- Consists on an hm2 electronic board connected to a display and a keyboard.

- It offers all the advantages of hm2 station (memorization, automatic measurement gathering, data extraction, etc.).

- Power supply is a 9 V battery.

- Allows data visualization in conductivity, humidity or temperature.

- Configurable through the keyboard.

4. Measurement interpretation

Humidec sensor provides very valuable information for the efficient irrigation control. Here are shown some situations that could be found when analysing the measurements.

Response of two sensors where it is observed that the water front arrives with certain delay after the irrigation has started. The delay is longer for the deeper sensor.

High conductivity attained at the beginning belongs to the liquid water filling the pores of soil. Once the excess liquid has percolated, only the water absorbed by the soil is measured by the sensor.

1. Evolution during irrigation:

4. Measurement interpretation

- Usually, a higher humidity level is observed in the deepest area (40 cm) due to the existence of water reservation.

- It is appreciated that between the 11th and the 19th the irrigation system was broken.

- When irrigation was performed again on the 19th, the deepest sensor does not detect water, since it is absorbed at the superficial area.

- It is at the third irrigation when water finally percolates and arrives at the deep area.

2. Very dried land:

5. Contact

For doubts, enquiries, or further information, do not hesitate to contact

Xop Física S. L.

The Company is located in Castellón de la Plana, in the Científic Park of the Universitat Jaume I.

Xop Física S. L.

Parc Científic EspaitecUniversitat Jaume I

12071 Castellón

Tlf: +34 964 38 73 51Fax: +34 964 72 92 18

E-mail: info@xopfisica.esWeb: www.xopfisica.es