Capacitive Soil Moisture Sensor - 3.3V/5V Analog Output, PH2.54-3P Interface

The sensor has a wide operating voltage range of 3.3 to 5.5 volts DC, thanks to its onboard voltage regulator. This makes it directly compatible with both 3.3V microcontrollers like ESP32 and 5V systems like standard Arduino boards without requiring an external level shifter.

Connect the sensor's 3-pin PH2.54 connector (Gravity interface) to your controller. The analog output pin connects to an ADC input on an Arduino. For Raspberry Pi, you will need an external ADC converter module (like an ADS1115) as the Pi lacks built-in analog inputs. The VCC and GND pins provide power.

Capacitive sensing measures the dielectric constant of the soil, which changes with water content, without passing a direct current through the soil. This eliminates the electrode corrosion and soil electrolysis that plague resistive sensors, resulting in significantly longer lifespan and more stable readings over time.

The sensor provides a 0 to approximately 3.0V DC analog output voltage. A higher voltage typically corresponds to drier soil (lower capacitance), while a lower voltage indicates wetter soil (higher capacitance). You will need to calibrate the sensor readings in your specific soil type to map voltage values to actual moisture percentages.

Yes, the sensing element is constructed from a corrosion-resistant material specifically designed for long-term soil exposure. However, the PCB and solder joints are not potted or fully sealed, so for permanent installation, consider applying a conformal coating or placing the sensor in a protective housing to further guard against prolonged moisture and mineral buildup.