3 ms·
For DIY, there was a pretty good discussion on suitable sensors in the AirGradient post from three months ago that Jeff linked to: https://news.ycombinator.com
by tpmx 5y ago
For DIY, there was a pretty good discussion on suitable sensors in the AirGradient post from three months ago that Jeff linked to:
https://news.ycombinator.com/item?id=27125060 https://news.ycombinator.com/item?id=27125060
tl;dr: seems like you want an NDIR sensor (https://en.wikipedia.org/wiki/Nondispersive_infrared_sensor https://en.wikipedia.org/wiki/Nondispersive_infrared_sensor).
Some options, with digikey @1 prices:
Senseair S8 (Sweden): $48
Sensirion SCD30 (Switzerland): $63
Amphenol Telaire T6713 (US): $96
If I were to buy an expensive black box iot solution, I'd at least verify that it had an NDIR sensor.
- s0rce 5y agoI'm using an SCD41 with an OLED+microcontroller (using Sensirion's example code hacked a bit) and it seems to work well, cheaper than the NDIR using some photoacoustic magic.
- tpmx 5y ago$37 @1, but not in stock at digikey, and an 11 week lead time. It's pretty tiny... I wonder if/when it will be possible to put a high quality co2 sensor in an IP68 iPhone...
- s0rce 5y agoI had purchased the dev kit sek-scd41 but its out of stock as well. The SCD41 also does RH and T so you don't need a separate sensor for that.