DFRobot - Gravity: Lab Grade Analog pH Sensor Kit for Arduino

This Gravity laboratory-grade analog pH sensor kit provides a practical starting point for an Arduino pH meter. The supplied BNC probe, signal board and analog cable bring the core measurement hardware together for water-quality experiments, aquarium sampling and aquaponics projects. A 0–14 pH measurement range and specified ±0.1pH accuracy at 25 ℃ support acidity and alkalinity testing after appropriate calibration. Gravity connectivity, an onboard adjustment potentiometer and a power indicator simplify setup. This kit is designed for intermittent laboratory-style measurements; the included probe should not remain immersed in the test liquid for extended periods.

Calibrated pH Measurement for Water-Testing Projects

This analog pH kit supports measuring acidic, neutral and alkaline samples across the stated pH range. The specified accuracy is ±0.1pH at 25 ℃, with calibration and a stable 5.00V supply important to measurement quality. An onboard gain-adjustment potentiometer supports the documented calibration workflow, and the Arduino example converts analog readings into pH values. Buffer solutions must be sourced separately, allowing the calibration reference to be selected around the samples being tested.

Probe, Signal Board and Gravity Cable in One Kit

This pH sensor kit includes the laboratory probe, signal-conditioning board and analog cable needed to connect the sensing hardware to a suitable Arduino analog input. The probe connects through BNC, while the board's PH2.0 interface carries the analog signal to the controller. A power indicator LED provides a quick check during setup. The compact plastic box with foam supports carrying and organizing the kit between experiments, while the probe still requires wet storage in the recommended KCl solution.

What is pH?  

“pH stands for the power of hydrogen, which is a measurement of the hydrogen ion concentration in the body. The total pH scale ranges from 1 to 14, with 7 considered to be neutral. A pH less than 7 is said to be acidic and solutions with a pH greater than 7 are basic or alkaline.” 

Note: Buffer solutions are not included. Gravity: Analog pH Sensor / Meter Pro Kit for Arduino and Gravity: Analog Industrial pH Sensor / Meter Pro Kit V2 are intended for testing in laboratory environments only, and the probes are subject to data drift after extended measurements. If you need to measure a solution for an extended period of time, we recommend using the Gravity: Analog pH Sensor / Meter Pro Kit for Arduino or Gravity: Analog Industrial pH Sensor / Meter Pro Kit V2.

After you received your package! You may found some white particles on the protection foam which is the KCl crystallization from the cap. Please don't worry about the crystallization in the packing box, that's normal. Actually, since the transportation restriction on liquid, we have poured out the KCL3N solution in the cap, the slight crystallization in the packing box should be leaked since the remnant. Anyway, once you received the probe, you should store it in KCL3N solution, you can not leave it in dry circumstances.

• Laboratory-grade probe for intermittent pH sampling
• 0–14 pH measurement range with specified ±0.1pH accuracy at 25 ℃
• BNC probe connector and Gravity PH2.0 analog interface
• Onboard gain-adjustment potentiometer and power indicator LED
• Probe, signal board and analog cable included
• Arduino measurement and calibration example available
• Compact plastic storage box with foam

• Laboratory-style water-quality testing
• Periodic aquaculture and aquarium pH sampling
• Aquaponics pH experiments
• Arduino-based DIY pH meters
• Educational acidity and alkalinity demonstrations

• Module Power: 5.00V
• Module Size : 43 x 32mm(1.69x1.26")
• Measuring Range :0 - 14PH
• Measuring Temperature: 0 - 60 ℃
• Accuracy : ± 0.1pH (25 ℃)
• Response Time: ≤ 1min
• pH Sensor with BNC Connector
• pH2.0 Interface (3-foot patch )
• Gain Adjustment Potentiometer
• Power Indicator LED

• Gravity: Analog pH Sensor / Meter Kit For Arduino x1
• pH probe (BNC connector)  x1
• pH sensor circuit board       x1
• Analog cable  x1