SN-3001-TR-ECTHPH-N01 RS485 Soil Four-Parameter Sensor - pH, Conductivity, Temperature, Moisture

The sensor uses the RS485 physical layer with the Modbus RTU protocol. To connect to a 5V microcontroller like an Arduino, you will need an RS485 to TTL/UART converter module (e.g., MAX485). For a Raspberry Pi, you can use a USB to RS485 adapter. The 5-pin connector typically follows a standard wiring: VCC, GND, A (Data+), B (Data-), and sometimes a shield ground.

The sensor supports a wide range of DC voltages: 5V, 12V, or 24V. Choose a voltage based on your system's available power rail and the required cable length. Higher voltages (12V or 24V) are recommended for long cable runs to mitigate voltage drop. Ensure your power supply can deliver at least 20 mA. The sensor's internal circuitry regulates this input to the appropriate levels for the sensing elements.

Yes, the probe is fully sealed with corrosion-resistant alloy electrodes, making it suitable for permanent burial in most soil types, including acidic or alkaline conditions. For accurate moisture and EC readings, ensure good soil-to-probe contact by backfilling firmly. The integrated design provides stable readings across various substrates, but for precise pH measurement, periodic calibration against standard buffer solutions is recommended.

pH calibration requires standard buffer solutions (typically pH 4.01, 6.86, and 9.18). The sensor must be cleaned and immersed in the buffers, with calibration values sent via Modbus commands. Conductivity (EC) calibration uses standard conductivity solutions. Detailed calibration procedures and the specific Modbus register map for setting calibration points are provided in the manufacturer's technical datasheet, which should be consulted for accurate setup.