Renke RS-SD-N01-TR-1 Soil Moisture Sensor - RS485/4-20mA/0-10V Output, IP68, SUS-304 Probe

The sensor is configurable for multiple industrial-standard outputs: RS485 Modbus RTU for networked data acquisition, a 4-20mA current loop for long-distance transmission with inherent noise immunity, and 0-5V or 0-10V analog voltage signals for direct connection to PLC analog input modules or microcontroller ADCs. The specific output is typically selected via internal DIP switches or configuration commands sent over the RS485 interface.

The sensor uses TDR (Time Domain Reflectometry), which measures the dielectric constant of the soil. This method is largely independent of soil texture and salinity, so factory calibration is generally sufficient for most applications, providing the stated accuracy in brown soil. For maximum precision in specific soil compositions (e.g., clay, sand, peat), a site-specific calibration can be performed by comparing sensor readings against gravimetric soil moisture samples.

Yes, its IP68 rating and construction make it ideal for permanent installation. The SUS-304 stainless steel probe resists corrosion, and the epoxy-sealed electronics compartment is fully protected against continuous submersion in water and dust ingress. Ensure connections are made using waterproof cable glands or junction boxes to maintain the integrity of the cable entry point.

Power requirements vary by output mode. The RS485 interface typically operates on a wide voltage range (e.g., 5-24V DC). The 4-20mA output requires a loop power supply, often 12-24V DC. The 0-5V and 0-10V analog voltage outputs also require a stable DC supply within the specified range (commonly 10-30V DC). Always consult the product datasheet for the exact voltage and current specifications for your chosen configuration.