Open Source Outdoor Air Quality Monitor

Post by jeffnappi » Sat, Jul 29, 2023, 10:05 PM UTC

cyberax wrote: post #37

ahaucnx wrote: post #33

Earlier quoted context omitted.

There are two main advantages of having two sensors: a) Data quality: You can detect if one sensor fails as the two readings will start to deviate and then replace the faulty one b) Extend the life of the monitor: The PM sensors with the laser and optics have a limited life. By having two inside, you can alternate the measurement and put them in sleep mode inbetween. Thus extending the life of the monitor.

Just a note: can you stagger the sensor time a bit unevenly? Instead of 50%/50% time split, can you do something like 40%/60%? This reduces the risk of both sensors failing at once because they have approximately the same duty time.

Post by smokelegend » Sat, Jul 29, 2023, 10:39 PM UTC

ahaucnx wrote: post #42

cvwright wrote: post #39

Earlier quoted context omitted.

This is random but I’d love to hear more about what’s involved in designing an enclosure and getting it manufactured at scale.

The tooling for the plastic enclosure was quite complex and time consuming. If there is interest I can write a blog post about it.

Post by [deleted] » Sat, Jul 29, 2023, 10:41 PM UTC

ahaucnx wrote: post #33

zerof1l wrote: post #31

I don't see any benefit in this product having two identical sensors side by side. Based on the datasheet, the reading between sensors is quite consistent, meaning that there's no improvement in accuracy. What would be better is to have two different sensors, one of which actually counts PM 10.0. A little-known fact about these air quality sensors is that they don't actually measure three different particle sizes, th…

There are two main advantages of having two sensors: a) Data quality: You can detect if one sensor fails as the two readings will start to deviate and then replace the faulty one b) Extend the life of the monitor: The PM sensors with the laser and optics have a limited life. By having two inside, you can alternate the measurement and put them in sleep mode inbetween. Thus extending the life of the monitor.

Post by dano » Sat, Jul 29, 2023, 11:12 PM UTC

ahaucnx wrote: post #2

I'm the founder of AirGradient and last year we have decided to focus our company on open hardware air quality monitors that we produce professionally. Our outdoor monitor Open Air has been designed from the start as an open hardware project with a beautiful plastic injected enclosure to demonstrate that open source hardware can look and perform on the same level like traditional products. We do also work intensively…

Post by simondotau » Sat, Jul 29, 2023, 11:44 PM UTC

cyberax wrote: post #35

stevep001 wrote: post #7

I'd be a buyer if you had an indoor unit with a radon sensor.

Why would you want a radon sensor in a product that does constant monitoring? Radon concentration is not a transient state, and you need to measure it for a fairly long time to get a good idea of the true concentration.