4 ms·
A freshly poured concrete structure with poor ventilation can go well below 400ppm.
by Robotbeat 4y ago
A freshly poured concrete structure with poor ventilation can go well below 400ppm.
- gambiting 4y agoSure, so like I said, you have a situation where a CO2 scrubber(in that case concrete) is present. If you need accurate measurement of CO2 below 400ppm and not just "it's less than 400ppm" then you need to buy a different sensor.
- Robotbeat 4y agoThis is a problem if you have a fairly well-sealed greenhouse as well. The CO2 level can go below 400ppm and reduce plant productivity. If you have a suggestion for a good but affordable CO2 sensor that can measure at or below 400ppm reliably, I’m all ears!
- gambiting 4y agoSo all Sensiron sensors are tuned for minimum 400ppm, other than this one: https://sensirion.com/products/catalog/STC31 https://sensirion.com/products/catalog/STC31 The problem is that it gives you percentage of CO2 in air instead of ppm, it can go all the way down to 0% though. I guess there must be a way to figure out the ppm based on that? I guess? Here's an example of a product with this sensor already integrated: https://www.sparkfun.com/products/18385 https://www.sparkfun.com/products/18385 Also I want to point out that their other sensors(SCD40 and SCD41) will actually give you a value even below 400ppm - just that their accuracy drops below that value. So it might say it's 300ppm when in reality it's 250ppm. Not sure how important it is for you.