Wrong PM, light and pressure values. Faulty kits?

[jgysenbergs1]

I’m sorry to mention this but after several days of observing data from two SCK 2.1 kits, I have to conclude something is very wrong:

• all PM data are erratic, sometimes way too high and sometimes nonexistent.
• light values are 0 most of the time.
• pressure value stays the same at around 100 K Pa with almost no variation.

Do I have a faulty kit and what can be done? Send me a new one? However, another kit not far from here has the same defects.

• Jos Gysenbergs, Kuringen Belgium

[oscgonfer]

Dear Jos,

Thanks for writting and apologies for late feedback.

Going one by one:

1. PM: could you post the links to your kits and give us a bit more of information about the installation conditions? Indoor, outdoor, clean air, next to the kitchen…
2. Light: We have been working on this problem. We are preparing a full blog post that will be uploaded in the Development insights category in one or two days. The firmware update and the process to upgrade it will be detailed in the post (and of course, in the docs)
3. Pressure: that’s absolutely normal, normal atmospheric pressure is around 1atm (101300 Pa or roughly 100kPa) You will see little variation in this sensor, but for instance before a storm it will go down and in a high heat days it will go up. The sensor’s is quite reactive and going up in a 5 floors building could also represent some changes, but still they will be around 100 kPa.

Let us know!

Óscar

[oldpitthouse]

Hi, my kit seems to have the same problem with the light sensor in that it only works intermittently. Also the CO2 and VOC sensors are tracking the humidity. (graphs virtually superimposable). https://smartcitizen.me/kits/9617. I was really disappointed when the kit arrived to see the NOx sensor had been dropped. We have been using NOx tubes locally for a year to measure this and were hoping to use the kit to get real time measurments rather than monthly averages. Great piece of work otherwise. Brian

[jgysenbergs1]

I’ll wait for better data till SCK2.1 has a proper casing. It’s covered by half a plastic bottle now, with PCBs held together with printed brackets. This works but as we have a heat wave here and almost no ventilation in the bottle, data may be affected by extreme temperatures.

[pral2a]

Hi!

Great you find a temporary solution for the enclosure.

We are working on a new design, too. We are documenting the process here:

2.1 Enclosure STL?

Hi! We are working on a new enclosure for the SCK 2.1 we will release soon! [SCK-21-NEW-ENC_EXPLODED] We currently have a basic enclosure design you can explore using recycled materials and a set of 3D printed clips. It’s not a fully rainproof enclosure but a way to start tinkering with new low-cost enclosure designs. [IhGxV67] Here the instructions: https://docs.smartcitizen.me/Smart%20Citizen%20Kit/#build-your-own-enclosure Here the 3D printed clips Hope this helps!

Also, we just released an updated for the light sensor issue.

The light sensor is fixed!

Hey everyone! This post is dedicated to talk about the issues and fixes of the light sensor readings that were found by many of you. There are only good news in this post, so don’t worry, it’s all under control! TL;DR Below we will talk about the sensor working principle and the current readings implementation. If you want to skip the post, the good news are that it only takes a little firmware update in 3 steps: Download the release from here Follow the update instructions from…

Hope it helps!