RoadTest: Sensirion Gas/Temp/Humidity Sensor Kit
Evaluation Type: Development Boards & Tools
Did you receive all parts the manufacturer stated would be included in the package?: True
What other parts do you consider comparable to this product?: Adafruit MiCS5524, SparkFun Environmental Combo Breakout - CCS811/BME280
What were the biggest problems encountered?: The odd board shape, my own stupidity not realizing that the Yun was a different arduino variant
I'll start with the one thing that struck me as odd about the board, its shape. Although its meant to be mounted on an arduino, somehow its set so that it hangs off the side. I think Sensirion must have a specific case design or something meant to utilize that as an air intake? Really hard to say.
Its turned 90 degrees from what I'd expect. Not that it really hampered development and since it is a development board it's not meant to directly put into production, but still odd. Note that I have an ethernet shield on the arduino, that wasn't used in Phase 1. I plan to do 2 or 3 more extended looks into this, with the next phase being a basic upload to some web service for log tracking, and also using this with a raspberry pi.
The product came in a nice little box, inside the box was the board in an ziplock antistatic bag. Also in the top of the box was printed a description and the URL for development resources. I found it handy, and spent a bit of time looking at what else Sensirion had available even if not applicable to this board. I was glad to see the ziplock bag as most dev products I've gotten are a 1 time bag, rip to open.
I currently only have 1 arduino board (an Elegoo Uno R3) as I've mostly been experimenting with Raspberry Pis due to language concerns My C/C++ is sort of weak, when I was first working on learning it I perpetually had memory leak issues. However, I've been developing software in varied other languages since the 90s. And the Pi allows for a much wider range, nowadays including the Microsoft .Net languages, which are my preferred working languages.
At a previous job, I used Pis as part of manufacturing floor monitoring equipment at a glass bottle plant. When I saw these I thought about how perfectly they'd fit in to that sort of environment to form a grid of monitoring. Generally VOCs were no worry at all, as the temperatures inside a glass plant would have them evaporate pretty rapidly, and they aren't used particularly in the process. But multi-point temp and humidity as well as the CO2 would be valuable as they'd have impact on glass quality as well as employee safety.
Following the directions on the Sensirion site I went to their github
Didn't need to actually clone the code locally, just grabbing the library from the Arduino IDE pulled in the 6 examples. They are in 3 sets, 2 for a "base" Arduino board, 2 for an Arduino Yun, and 2 for the Arduino LinkIt. The base sample code installed and ran with no issues producing a straightforward output in the serial monitor.
I played around with blowing on it, holding an open bottle of rubbing alcohol near it etc to see the values change. It worked well, the changes for CO2 and VOC were rapid and strong. These results are from just opening up a bottle of rubbing alcohol within a few inches of the board.
Summary for Phase 1
Easy enough to use, reasonably inexpensive as a development board. For real production use, you might not choose to have the full sensor pack - ie you'd pick what individual components you needed for the application.
For someone wanting to experiment with air quality testing including temp + humidity this seems like a nice choice and outside of the board piece hanging off the side a nice package. I'm sure there's a good reason for the overhang, if anyone else knows please leave a comment. I'm used to the Pi hats, and haven't used much in the way of Arduino shields in the past.
One thing I need to follow up on, and do some outside research on is what the CO2 + VOC numbers mean, and what is considered normal vs unsafe levels of each. I'll be doing that before phase 2 of this review, which will be using this setup with the ethernet board powered by PoE as an in house monitor. Doesn't do me much good to monitor if I have no idea what the scale means
Thanks for reading!
It was a complaint I had with the SparkFun CCS811/BMC200 dev board. The two sensors were very close to each other. The MOX hotplate in the tVOC sensor was less than half a centimeter from the temp sensor and the whole board needed to be placed well away from anything else in my enclosure or else it simply read the temp of the entire assembly.
The PCB form takes care that you measure the environment temp (and other metrics), instead of the temp above the Arduino CPU.