Silo filling monitoring
In agriculture, one of the routine tasks is the timely filling of silos. The silo level sensor continuously and at a given interval measures the filling level and transmits data to the server via a radio channel.
Suitable for any silo or container from 1.2 meters in diameter, regardless of the structure of the walls and the composition of the stored material.
It has a filling measurement accuracy of 4 centimeters, operates on a battery for several years, is attached with magnets, and transmits data for tens of kilometers via a radio channel. What else should a silo sensor be able to do?
- from -40°C to +85°C
- Protection class: IP67
- Mounting on movable magnets
- Protection against falling into silos
- Internal or external antenna placed on the silo or internal
- Measurement accuracy 4 cm
- Notifications of changes by 5%
- Data relevance: not less than 30 minutes
- Dimensions 120×120×92 mm
- Power supply: internal 34 615 (D class)
- Weight: 455 grams
- Frequency range: 863-870 MHz
- Transmission range: up to 50 km
- LPWAN GoodWAN/OpenUNB
Agriculture
Currently, several methods for determining the degree of filling are widely used - from hitting the body with a special hammer to expensive measuring devices. However, they all have their drawbacks.
Mechanical sensors can assess the presence of filling at the level of the sensor installation. The higher the silo and the more control points, the more sensors are required and the higher the probability of failure and the need to carry out work inside the silo.
Ultrasonic and optical sensors (including laser) are afraid of contamination (dusting) of the sensor surface, and dust flying in the air distorts measurements or does not allow them to be taken at all. In addition, the laser sensor provides control at one point, which does not work well in conditions of bulk materials, which can accumulate in a pile or, conversely, have a "hole" in the middle when the material is consumed.
The reflectivity of the material in the silo, for example, compound feed, also imposes restrictions on the technologies used.
Microwave distance sensors can be used in silos. However, the silo body itself introduces a lot of noise - since the reflection from the body can be several orders of magnitude stronger than the reflection from the measured material. The silo walls can be corrugated, which distorts the signal even more.
All this makes the task of measuring the level of materials in a silo in a contactless way non-trivial. Our engineers have created a device that not only solves the problem of measuring the level with an accuracy of up to a centimeter, but were able to make the sensor wireless and operate for several years on a battery.
To simplify installation, the sensor has legs with 3 powerful magnets, which allow it to be placed on the inside of the silo lid. The antenna is placed on the outer surface of the silo and is also attached to the magnet.
The accuracy of distance measurement by the sensor is 4 cm! Taking into account the volume of typical silos, filling can be measured with an accuracy of up to a fraction of a percent. However, due to the characteristics of bulk materials, which can pour out unevenly, we have programmatically reduced the accuracy to an acceptable level.
The sensor transmits data once every 30 minutes or when the level changes by more than 5%.
