Many clients use our Arduino UART examples and Arduino source code to connect the popular SenseAir K-30 sensor to Arduino boards. However, these examples were all created before the SenseAir S8 CO2 Sensor was developed. So we were surprised when a client recently wrote us:
"To my surprise, the script you give for the K30 sensor works out of the box with the S8! Why don't you mention it in the app note? Had I known that from the start, I wouldn't have bothered you about which sensor to buy..."
Frankly, we were a bit sheepish. In all the projects we work on, somehow testing the SenseAir S8 with the Arduino code never occurred to us.
What are the advantages of the S8?
The S8 Miniature CO2 Sensor is the smallest non-dispersive infrared (NDIR) sensor on the market today. Due to its optical path design, it can accurately measure carbon dioxide levels up to 2% with extended range measurement up to 3.2% by volume and a second option of 1% (0-10,000 ppm) for lower concentrations.
Unlike the K-30 sensor which is designed to report CO2 levels in real-time, the S8 is designed to be used as a carbon dioxide safety switch. During normal operation, the sensor measures ambient CO2 concentration and compares the result with a user-programmed high-level set point. If high CO2 levels are detected, a programmable open collector circuit outputs a logic OR alarm.
With similar pricing, Arduino enthusiasts now have two different CO2 sensors to consider for their projects.