Designed based on the principle of dielectric constant and featuring helical measurement electrodes, the tubular soil temperature and moisture monitor outputs data via the RS-485 Modbus RTU protocol. It is capable of simultaneously measuring soil temperature, moisture, and electrical conductivity across 3 to 10 layers, making it widely applicable in agricultural engineering fields such as smart greenhouses, orchards, and irrigation systems.
The tubular soil temperature and moisture monitor is an online device designed to track soil profile temperature, moisture, and electrical conductivity. Integrating these measurement functions into a single unit, it is extensively used in smart agriculture applications, including greenhouses, orchards, and intelligent irrigation systems.
Regarding measurement principles, the device establishes a mathematical model based on the soil's dielectric constant and utilizes helical electrodes to measure volumetric soil water content. It employs a stratified observation structure, featuring a temperature monitoring point at the surface and additional soil measurement points spaced every 10 cm underground. The number of monitoring layers is customizable, supporting a range from a minimum of three layers to a maximum of ten. The housing is constructed from PVC or imported PC material; internally, the device emits high-frequency (approx. 1 GHz) detection waves that penetrate the casing to effectively sense the soil environment. Because the electrodes do not make direct contact with the soil, electrical interference with the soil and plants is avoided, and the device remains unaffected by soil salt ions; agricultural activities such as fertilization, pesticide application, and irrigation do not compromise measurement accuracy.
In terms of technical specifications, the monitor features a sensor startup time of 60 seconds, operates on 12V DC power with a current of 22mA, and has a power consumption of 0.26W. It utilizes the RS-485 Modbus RTU communication protocol. The soil temperature measurement range is -30°C to 70°C with an accuracy of ±0.3°C; the soil moisture range is 0% to 99% with an accuracy of ±3%; and the soil electrical conductivity range is 0 to 20,000 μS/cm. With an IP67 waterproof rating, the instrument is suitable for long-term, continuous field monitoring. In terms of practical application, the tubular soil temperature and moisture monitor enables agricultural professionals to track actual soil moisture and temperature levels, facilitating precision irrigation tailored to crop growth requirements. Monitoring these soil parameters allows for the scientific and rational allocation of water resources, ultimately enhancing crop yield and quality. The device features an integrated cloud-based data management platform and a mobile app, supports 4G or RS485 communication, and allows users to view data in real-time via web browsers or mobile devices. It is suitable for soil monitoring operations conducted by agricultural and rural affairs bureaus, universities, research institutes, water conservancy bureaus, and environmental protection agencies.
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