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Gravity: Analog TDS Sensor/Meter for Arduino - DFRobot

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SKU: DF-SEN0244
Sale price 16,45 €
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Effective Date: December 10, 2025

At OpenELAB, we are committed to providing accurate product descriptions and high-quality electronics. The following policy outlines your rights and obligations, designed to be fair to both our customers and our business operations globally.

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Depending on the severity of the usage/damage, the deduction may range from 15% to 50% of the product price. Items damaged beyond repair due to misuse will not be refunded.

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  2. RMA Number: We will provide you with a Return Merchandise Authorization (RMA) number and the correct return address.

  3. Packing: Ship the item back in its original packaging with the RMA number clearly marked on the shipping label (not on the product box).

  4. Tracking: We strongly recommend using a trackable shipping method. OpenELAB is not responsible for returns lost in transit.
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Gravity: Analog TDS Sensor/ Meter for Arduino-1

Gravity: Analog TDS Sensor/Meter for Arduino - DFRobot

16,45 €

The Gravity Analog TDS Sensor/Meter is an Arduino-compatible water quality sensor designed by DFRobot to measure TDS (Total Dissolved Solids) in water. As a reliable TDS meter solution, it reflects the cleanliness and purity of water by measuring how many soluble solids are present. This TDS sensor is ideal for domestic water, hydroponics, and general liquid testing with any Arduino board.

With a clear analog output and waterproof probe design, this TDS meter sensor kit allows you to easily build DIY TDS meters or automated water monitoring systems. This DFRobot TDS sensor is plug-and-play for Arduino beginners and professional makers alike.

 

How the TDS Meter Works

TDS measures the total amount of dissolved substances in water (in ppm). The higher the TDS reading on your TDS meter, the more impurities the water contains. Ideal drinking water typically has TDS < 300 ppm, while values above 500 ppm are considered contaminated. Using an Arduino TDS sensor allows for real-time tracking of these levels.

The Gravity TDS sensor module converts water quality data into a 0~2.3V analog output, which can be read by any Arduino analog input pin. The excitation source of this DFRobot TDS meter is AC to prevent polarization, improving probe durability and measurement stability for long-term water quality sensing.

 

Features of the Gravity TDS Sensor

  • Wide Voltage Support: Operates from 3.3V to 5.5V, compatible with most Arduino microcontrollers
  • Analog Output: 0 – 2.3V, compatible with 3.3V / 5V systems like Arduino Uno or ESP32
  • Waterproof TDS Probe: Designed for long-term immersion and continuous TDS measurement
  • AC Excitation Source: Prevents probe polarization in your DIY TDS meter project
  • Easy Arduino Integration: No soldering needed, Gravity connector for plug-and-play use
  • Affordable TDS Meter alternative: High-quality TDS sensor performance compared to professional testers

 

TDS Meter Applications

  • Domestic water testing for purity
  • Hydroponic nutrient monitoring using Arduino
  • Aquarium water quality control with a TDS sensor
  • Agriculture irrigation systems and liquid testing
  • Environmental science education involving TDS meters
  • Smart water purifiers (recommend pairing this DFRobot sensor with Gravity: Waterproof DS18B20)

 

Technical Specifications

Signal Transmitter Board

Parameter Value
Input Voltage (Arduino Compatible) 3.3V ~ 5.5V
Output Voltage (TDS Signal) 0 ~ 2.3V
Working Current 3 ~ 6mA
TDS Measurement Range 0 ~ 1000 ppm
TDS Meter Accuracy ±10% F.S. (at 25°C)
Size 42 × 32 mm
Module Interface Gravity PH2.0-3P
Probe Interface XH2.54-2P

 

Waterproof TDS Probe

Parameter Value
Needle Count 2
TDS Probe Length 83 cm
Connector Type XH2.54-2P
Color Black
Waterproof Rating Yes (probe head & cable only)

Note: The TDS meter signal board is not waterproof. Avoid water contact beyond the TDS probe.

 

Real Projects Using This Arduino TDS Sensor

1. Arduino Hydroponics Monitoring System
Measure water nutrient content with the DFRobot TDS meter alongside pH/EC sensors.

2. Water Quality TDS Meter Display with LCD
Read real-time TDS sensor values on an Arduino LCD screen.

3. IoT Water Monitoring (ESP32 + Bluetooth TDS Meter)
Send TDS sensor data to smartphones and monitor water purity remotely.

4. Filter Comparison TDS Meter Experiment
Compare water quality before and after filtration using this Arduino TDS meter.

5. Water Quality Monitoring with Gravity TDS Sensor and LCD Display

Introduction: This project demonstrates how to interface the Gravity Analog TDS Sensor with an Arduino to measure TDS levels in water and display the results using a TDS meter interface on a 16×2 LCD screen. It's an effective DFRobot solution for visualizing water quality in PPM.

DFROBOT TDS Meter Sensor With Arduino and LCD

 

Shipping List

  • 1 × Analog TDS Meter for Arduino (Signal Board)
  • 1 × Waterproof TDS Probe for TDS Sensor
  • 1 × Gravity 3-Pin Analog Sensor Cable

 

Reference

TDS Meter Product Wiki

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