We do not recommend this combination due to the nature of the sensor and complexity of continuous need for calibration. However, we have done this to demonstrate it is possible.
In general, our sensors are simple to use with an Arduino microcontroller using our Vernier Arduino® Interface Shield (BT-ARD). We have a number of sample sketches on our website, demonstrating how to use them with an Arduino.
Our ion-selective electrodes (ISEs) require special consideration. Please note our ISEs are not designed for long-term, continuous use. They are designed for educational lab applications where sensors are calibrated, and tests are conducted and completed in a short time period. In no circumstances should the sensor be submerged in a solution for greater than 24 hours. Read the ISE sensor user manual carefully to make sure this sensor is appropriate for your application.
The sensor converts a 0-5 V reading into a mV output. The mV reading then corresponds to the concentration of the ion for the particular ISE you are using.
If you are interested in using an ISE with an Arduino, you need to create a sketch that performs the following conversions:
- Convert raw Arduino reading to a 0-5 V range.
- Convert 0-5 V range to mV using E = 137.55*Voltage -168.2 where E is the response in mV and the Voltage is the voltage from the sensor.
- Convert mV to an ISE sensor reading.
The ISE response is modeled by the Nernst Equation. Refer to the sensor’s user manual for information on this calibration equation. Note: The ISE sensor membranes have a limited shelf-life and change over time, so this third step requires regular evaluation (perhaps every use) to keep the sensor appropriately calibrated.
We have posted an Arduino sketch on github that reads a Vernier ISE sensor. This sketch can be found at
Please note that our equipment is not designed nor is it recommended for any apparatus involved with any industrial or commercial process such as life support, patient diagnosis, control of a manufacturing process, or industrial testing of any kind. Our equipment is to be used for educational purposes only.