Arduino pH sensor: Difference between revisions
From wikiluntti
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The pH electrode | The pH electrode | ||
* a passive sensor | * a passive sensor | ||
See more about impedance and Arduino ADC at https://www.e-tinkers.com/2020/07/a-review-on-seeed-studio-ph-and-ec-sensor-kits-part-1/ | |||
== Calibration == | == Calibration == | ||
Revision as of 14:51, 3 March 2026
Introduction
3 major commercially available or mass-produced solutions:
- Atlas Scientific and Gravity analog pH Kit with board, sensor and buffer solutions. Hiqh quality, not open source.
- DFRobot Gravity: Analog pH Sensor Kit
- Other (Chinese) manufacturers.
- Seeed Studio
If the pH electrode is labotorary grade, it is not designed for submerging into measuring solution permanently. Thus, use an industrial-grade pH electrode (lifecycle about 3 years), but calibrate it at least twice every year.
Theory
An ideal pH sensor because H+ ions. Ranging linearly:
- U = 0 @ pH 7
- U > 0 @ pH < 7
- U < 0 @ pH > 7
A high quality op amp is needed to amplify the voltage.
The pH electrode
- a passive sensor
See more about impedance and Arduino ADC at https://www.e-tinkers.com/2020/07/a-review-on-seeed-studio-ph-and-ec-sensor-kits-part-1/
Calibration
Code
References
https://www.e-tinkers.com/2019/11/measure-ph-with-a-low-cost-arduino-ph-sensor-board/
