Soil moisture sensors is a kind of sensor for agriculture and the product of intelligent agriculture. It can measure the temperature and humidity of soil and is suitable for soil moisture detection, water-saving irrigation, greenhouse control, fine agriculture, road detection, hydrometeorology and other scenarios.
Relative to the soil temperature sensor, the types of soil moisture sensor will be more, according to its measurement principle, generally divided into capacitive type, resistance type, ion sensitive type.
Capacitive soil moisture sensor
Capacitive soil moisture sensor sensitive element is humidity sensitive capacitor, the main material is metal oxide, polymer.
These materials have strong adsorption capacity for water molecules, and the amount of adsorbed water varies with the change of environmental humidity. When the ambient humidity changes, the permittivity of the humidity sensitive capacitor changes, so that its capacitance also changes. The capacitance change is proportional to the relative humidity, which can be used to measure the humidity.
The temperature measurement range of soil moisture sensors is mostly in: -20℃-80℃, the humidity measurement range is mostly in: 0-100%RH, the temperature accuracy is mostly in: 0.5℃, the humidity accuracy is mostly in: 0-53% ±3%,53%-100% ±5%, the parameter range is different according to the selected configuration.
Are soil moisture meters accurate?
Yes, a soil moisture meter provides a numerical measure, which is more sensitive than the touch-and-feel method many gardeners use. Most inexpensive analog meters provide a measure on a 1-to-10 scale, which is accurate enough for the average gardener.