Soil water potential sensor

1. Product Introduction of Soil Water Potential Sensor

Soil water potential sensor, also known as soil moisture sensor and soil water potential measuring instrument, is a soil water potential sensor suitable for field installation and long-term monitoring. It is easy to install, easy to maintain, and very simple to measure and record. Plug and play, measurement Soil water potential or substrate potential. The growth of plants requires a certain amount of soil water, and the content of soil water has an important impact on plant growth and development. With the development of agriculture, the requirements for crop yield and quality are getting higher and higher, so it is necessary to know the precise irrigation cycle of plants and give them an irrigation time point. Soil tension sensors can give such an irrigation point. It can clearly inform growers whether plants are short of water, how long it will be short of water, and how often to irrigate, thereby improving the quality of crop products.

In modern agriculture, the role of soil tension sensors is very significant. After the soil tension sensor collects the data of the dynamic content of soil moisture in the planted crops, more precise irrigation measures can be carried out according to the growth of the crops, which can not only record the data of soil tension changes, but also help growers to continuously replenish the soil of crop types Environmental data is of great significance for improving crop varieties, improving crop quality and yield.

The product uses a transparent PVC plastic tube, which can clearly see the amount of remaining water in the equipment, which is convenient for adding water. At the same time, it uses a -100-0Kpa vacuum gauge, which is convenient for users to view the data clearly. The product is suitable for places where soil moisture and drought information need to be detected. It is mostly used in agricultural crop planting to monitor whether the crops are short of water, so as to better irrigate the crops.

When the interior of the pvc pipe of the equipment is filled with water, the pressure inside the pvc pipe is 0 compared to the atmospheric pressure. After the equipment is inserted into the soil, part of the water inside the pvc will be absorbed by the soil, resulting in negative pressure inside the pipe. The greater the absolute value of the negative pressure in a standard unit time, the stronger the water absorption capacity of the soil and the more water-deficient the soil.

2. Product Features of Soil Water Potential Sensor

1. Protection level: IP67

2. The structure of the whole machine: the product adopts the bottom monitoring structure, insert the bottom of the equipment into the soil to the depth that needs to be monitored, and the specific insertion depth can be customized according to the site requirements.

3. Equipment size: the insertion depth is 60cm, and an integral multiple of 15CM can be added, up to 120cm.

4. Maximum power consumption: 0.8W (24V DC power supply)

5. Equipment material: transparent PVC plastic tube, which can clearly see the amount of remaining water in the equipment, and it is convenient to add water.

6. Communication interface: RS485.

7. Power supply mode: 5-30vdc wide voltage power supply.

8. Working environment: 0℃~+60℃.

9. Default accuracy: ±0.5kpa (25°C).

10. Range: -100kpa~0kpa

11. Resolution: 0.1kpa

3. How to install the soil water potential sensor

1. Installation location

Install the equipment after the crops are sown; the equipment installation location should be a relatively high and flat place to prevent rainwater from pouring back into the equipment and causing equipment short circuits or line failures.

Under the condition of comprehensive irrigation, the area with less water is preferred as the monitoring location; under the condition of partial irrigation, the wet area is selected as the monitoring location;

Select the location where the crop growth is balanced and can represent the growth of most crops;

To understand the root distribution of the monitored crops, generally choose a location closer to the water-absorbing roots of the crops to determine the height of the equipment.

2. Installation method

The installation method is perforated and grouted, please refer to the manual for details.

3. Installation method

Prepare cold boiled water: After boiling tap water for 20 minutes, let it cool for later use.

Clay head exhaust: Inject cold boiled water, fill it up, stand the instrument upright for 10-40 minutes (do not cover it), and see water dripping from the surface of the clay head, then plug the silicone plug, wrap the clay head with a paper towel to absorb water, make When the soil tension reaches about -40kpa, if you see bubbles rising, you can also shake the device to exhaust as much as possible, and repeat this process 2-3 times.

Submerge the clay head into the water, wait for the soil tension to return to less than -10kpa, fill it up with water again, plug the silicone plug, screw on the top end cap, and set it aside.

4. Precautions

The clay head must not be oily, so as not to block the micropores and cause the instrument to fail.

The measuring range of the instrument is -100Kpa-0. When it exceeds this limit, the instrument will leak air due to the rupture of the clay head tube wall, making the instrument useless.

Regularly check, fill the sensor with cold boiled water, once every half a month to a month (or add water when the water level drops to the top of the air collecting pipe), do not loosen the sensor during the filling process.

Before the temperature drops to 0°C, the outdoor instruments should be withdrawn to avoid freezing and cracking.

-10~0kpa means humidity, which is too high for most crops.

-30~-10kpa means humidity, suitable for the growth of most crops.

-50~-30kpa, means dry, wet crops need to be irrigated.

<-50kpa, it means dry and most crops need to be irrigated.