Gravity Analog TDS Sensor Meter for Water Purity

The Gravity TDS sensor from DFRobot measures the TDS value of water, i.e. the amount of dissolved solids in ppm, and thus indicates the purity of the water. The signal board drives the probe with AC voltage, which prevents polarisation of the electrodes. The analog output delivers 0 to 2.3 V and suits 3.3 V and 5 V boards such as Arduino or ESP32.

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:

• Dupont Cables M-M 10cm 20 Pieces
• Gravity DS18B20 Sensor Kit

Features:

• Measuring range 0 to 1000 ppm, accuracy ±10 % of full scale at 25 °C
• AC excitation against polarisation of the probe
• Waterproof probe with 2 needles, total length 83 cm
• Probe head and cable are waterproof, connector and signal board are not
• The probe has no temperature sensor; the temperature compensation in the example code needs a separate waterproof temperature sensor, otherwise it calculates with 25 °C (DFRobot)
• Do not use the probe in water above 55 °C and do not place it too close to the edge of the container (DFRobot)
• Example code for Arduino with calibration using a reference solution

Application Examples:

• Monitoring drinking water and water filters
• Nutrient solution in hydroponics and aquariums in the range up to 1000 ppm
• Comparing water samples in class
• Data logger for water quality

Documentation:

• Wiki DFRobot SEN0244 with calibration and example code for Arduino
• Arduino example by DFRobot
• Library GravityTDS (GitHub)
• Schematic (PDF)

Technical Data:

• Manufacturer: DFRobot
• Manufacturer SKU: SEN0244
• Input voltage: 3.3 to 5.5 V
• Output voltage: 0 to 2.3 V analog
• Current consumption: 3 to 6 mA
• Measuring range: 0 to 1000 ppm
• Accuracy: ±10 % F.S. (25 °C)
• Signal board connector: PH2.0 3-pin, pins − (GND), + (VCC), A (signal)
• Probe connector: XH2.54 2-pin
• Probe: 2 needles, total length 83 cm, black
• Signal board dimensions: 42 × 32 mm
• Weight: 35 g

Scope of Delivery:

• 1× Gravity Analog TDS Sensor signal board
• 1× Waterproof TDS probe
• 1× Gravity analog sensor cable 3-pin, 30 cm