Are the sensors pre-calibrated? I found that you can easily get cheap air quality sensors from China, the problem is that they could do better with calibration, which may require expensive (in relation to the sensor itself) equipment.
Show HN: Enviro+ for Raspberry Pi – Environmental sensors
41–50 of 83 posts
Re: Show HN: Enviro+ for Raspberry Pi – Environmental sensors
#42Earlier quoted context omitted.
This product works with any model of Raspberry Pi - it doesn't have to be a Pi Zero! The Pi Zero comes in three flavours - the Pi Zero WH includes a pre-soldered header. :-)
ah, I didn't realise it was actually coming out of the fab like that now? I could have sworn that at least initially, it was being offered as a value-add service. Anyway, I should stress it wasn't a criticism - just that if that's their biggest question, they'd probably benefit from being able to tell the bare & WH boards apart.
Re: Show HN: Enviro+ for Raspberry Pi – Environmental sensors
#43Very similar to Pioneer600, an expansion board for Raspberry Pi. https://www.waveshare.com/pioneer600.htm
Re: Show HN: Enviro+ for Raspberry Pi – Environmental sensors
#44- https://www.researchgate.net/publication/325416608_Suitabili...
- https://www.scientevents.com/proscience/download/potential-a...
They are often easy to set up, but make sure to double-check just how much you can use your particular model for.
Re: Show HN: Enviro+ for Raspberry Pi – Environmental sensors
#45Are the sensors pre-calibrated? I found that you can easily get cheap air quality sensors from China, the problem is that they could do better with calibration, which may require expensive (in relation to the sensor itself) equipment.
You can easily calibrate co2 , 02 and n2 sensors by going outside in a "wild/nature" place
Re: Show HN: Enviro+ for Raspberry Pi – Environmental sensors
#46Re: Show HN: Enviro+ for Raspberry Pi – Environmental sensors
#47Weirdly coincidental timing on this! I've been working on a PCB design (FeatherWing form factor) to track weather data on my hikes, making use of a BME280 and a GPS module. First revision of the board[1], I discovered that the sensors started out accurate, then drifted up to a steady 3° above ambient. Probably because the GPS module was heating up. So last night I found myself reading up on design considerations for…
Additionally, when I do my designs, I place the BME280 sensor as far away from other components as possible (I see it is close to a SOIC chip on your board) and I route a cutout in the board around the sensor to reduce any heat conduction from the board. I also ensure that I have no power planes on the little resulting "island" PCB, and use small traces (with local decoupling) to further reduce any conductive heat. See the image in [2] for an example of what I am talking about.
Another alternative I pursued in situations where convective heat was an issue is to stick the sensor on a little remote board and use an off-the-shelf wire to connect the two (check out the Sparkfun Qwiic wires[3])
Overall you want to increase airflow around the sensor as much as possible so leaving it "hanging out" somewhere is the best approach to getting accurate measurements.
I hope that helps!
[1] http://www.kandrsmith.org/RJS/Misc/Hygrometers/calib_many.ht...
[2] https://www.instructables.com/id/How-to-Measure-Temperature-...
Re: Show HN: Enviro+ for Raspberry Pi – Environmental sensors
#48Earlier quoted context omitted.
Which sensor are you looking at? I'm sure it could run alongside the rest of Enviro+!
The most likely candidate is the TelAire T6613 [1]. Like most sensors in this price range, it reports data on I2C. [1] https://www.co2meter.com/collections/0-1-co2/products/t6613-...
[1] https://www.co2meter.com/products/k-30-co2-sensor-module
Re: Show HN: Enviro+ for Raspberry Pi – Environmental sensors
#49Re: Show HN: Enviro+ for Raspberry Pi – Environmental sensors
#50Does anyone know where I can buy one of those displays? Looks amazing for the size and it has a standard connector instead of the weird hot-bar solderable ones on the other small displays I have seen.