capacitive soil moisture sensor

Kingmach capacitive soil moisture sensors measure volumetric water content by detecting changes in the dielectric permittivity of the soil. The sensing element is sealed inside a durable PVC or stainless steel body, which resists corrosion and mechanical wear. Output signal is typically 0-2.5V or 0-5V, but we can configure 4-20mA or RS485 on request. Power consumption stays low—around 3mA during measurement—which lets you run them on battery-powered loggers for months. Installation is straightforward: dig a hole to the target depth, insert the probe, and backfill carefully to avoid air gaps. For hard or stony soils, we recommend using the optional pilot tool. The standard cable is 5 meters, with extensions up to 50 meters possible. When you need sensors for a network, each unit comes with its own calibration coefficients, though you can also apply a general calibration for mineral soils. The electronics are potted in epoxy, rated for IP68 submersion, so they handle wet environments well. Operating temperature ranges from -20°C to 60°C, covering most field conditions. If you need sensors for frozen soil research, we can provide low-temperature variants. These sensors find use in agriculture, environmental research, landslide early warning systems, and landfill cover monitoring. We keep common models in stock and can ship within a week for small orders. For bulk or custom requirements, our engineering team assists with integrating the sensors into your existing monitoring platform.