Hey all,
A couple of weeks ago I posted my 3D printable pegboard organizers, and today I’m releasing the Only Sensor line of home automation sensors.
Fully free and open, complete with wiring diagrams, cases, component bill of materials, and instructions for assembly.
You source and build them yourself, with acquisition costs ranging from $2-$35 to build, and options for:
- mmWave presence
- PIR motion detection
- Temperature
- Humidity
- LUX
- PM <10µm AQI
- PM <2.5µm AQI
- PM <1µm AQI
- NOX
- VOC
All integrate with Home Assistant via ESPHome.
All the details can be found at: https://nowsci.com/only-sensor/
Those dht11 sensors are garbage tho. Best case they are wildly off on their humidity sensor. Worst case they keep breaking and shows nonsense readings. I would recommend bme280 sensor instead. If you read about them you might see people complain that they are reading too high temperatures, but in my experience its because they are misconfigured. Default settings have a very high sampling rate of multiple samples per second that heats up the sensor a tiny bit giving you the offset. Lowering the sampling rate or turn the sensor off completely in between readings gives really precise measurements on both temperatures and humidity.
Very nice.
It’s missing CO2, but those are expensive so that’s understandable. If you need one of those, I think https://www.airgradient.com/ is a great choice.
I’ve had another user say the same thing, so I’ve considered investigating CO2. What’s the rationale to you for wanting it?
I don’t have HVAC, so I’m just using it to see when the air at my desk is getting stale so I remember to open the window. I mostly use homeassistant for the configuration, although I might also set up a notification at some point (I only got my sensor 2 days ago)
Not speaking for Mr Lemon, but for me CO2 levels are an interesting metric to trigger my air exchanger / HVAC fan combo for in a given zone, since it indicates stale air in general.
Same ^
CO2 sensor for me is the most important.
you will need to update the firmware on the LD2450. You do this with a mobile app called HLKRadarTool
Does this seem sketchy to anyone?
It certainly did to me when I made these. I ended up using an old Android phone for that part, but many members of the ESPHome community working with these sensors use it and have never reported a problem. HLK are the original manufacturers of the LD radar chips.
No, why?
If anyone like me is wondering what:
- PM <10µm AQI
- PM <2.5µm AQI
- PM <1µm AQI
…means it’s air quality. These measurements are referring to different sizes of particulate matter (PM) and their corresponding Air Quality Index (AQI) value
Yup! The ESPHome config also converts these into a standard AQI that you’re used to seeing.
Amazing! This is great work!
Thanks! They were fun to build and design for sure.
Hey now! The only sensor I’ll need is actually 4?! /jk
This is awesome!
Thanks!
Man, I wish this had been a thing ~8 months ago when I was building these for my stuff.
…mine are awful, and these look awesome, so maybe it’s time to re-do that.
Weellll… In usual fashion for my projects, I made these about that long ago, just tested them for a long time before doing the write-ups.
This is incredible!
Thanks!
