DFRobot Capacitive Soil Moisture Sensor

This capacitive soil moisture sensor from DFRobot measures the moisture of the soil and detects when a plant needs watering. The probe is inserted into the soil and measures the capacitance, which changes with moisture. The sensor outputs an analogue voltage of 0 to 3 V and connects directly to an analogue input, for example on an Arduino. It has no wear and no corrosion like a conventional resistive sensor and therefore lasts longer.

Important: The cut edges of the board are not sealed, and moisture can enter the circuit board through them. For a longer service life, seal the edges with clear varnish or epoxy resin.

Recommended alternative in waterproof design: DFRobot waterproof capacitive soil moisture sensor

Note: The connection cable can be converted to male pins with a Dupont cable M-M, so that it also fits an Arduino UNO.

Recommended Accessories:

• Micro Water Pump Horizontal 100L/h 3-6V with Hose
• Micro Water Pump 120L/h 2.5-6V
• Dupont Cables M-M 10cm 20 Pieces
• Gravity 16Bit 4-Channel ADC Analog Digital Converter I2C ADS1115

Features:

• Capacitive measuring principle with TLC555 timer chip
• XC6206P302 voltage regulator on the board, operation with 3.3 V and 5 V
• Analogue output 0 to 3 V
• Gravity PH2.0 3-pin connector, cable included
• Before use, measure the values in dry air and in water and use them as limits, as described by DFRobot
• On the Raspberry Pi only with an external A/D converter such as the ADS1115, as the Pi has no analog input

Application Examples:

• Monitoring plants in pots or the garden
• Automatic irrigation with a pump
• Measuring soil moisture in greenhouses

Documentation:

• DFRobot Wiki with pinout and example code
• Schematic (PDF)

Technical Data:

• Manufacturer: DFRobot (SEN0193)
• Operating voltage: 3.3 to 5.5 V DC
• Operating current: 5 mA
• Analogue output voltage: 0 to 3 V DC
• Voltage regulator: XC6206P302
• Chip: TLC555CDR
• Connector: PH2.0, 3-pin
• Cable length: 30 cm
• Colour: black
• Dimensions: 98 × 23 × 7 mm
• Weight: 15 g

Scope of Delivery:

• 1× DFRobot Capacitive Soil Moisture Sensor
• 1× connection cable 30 cm