Air Quality Monitors
20 Dec 2020 ∞
Over the summer, while California was in the middle of fire season I decided , mostly out of a morbid curiosity I suppose, to monitor the air quality inside my house. There are a number of commercial solutions available, however they're all either complex, costly, or both. I was looking for something that could take the place of my existing Wemos & ESPHome-based temperature and humidity sensors.
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After a bit of research I found the PMS5003T, which measures PM 2.5, temperature, and humidity. The sensor uses a tiny ribbon cable, so they can't be connected directly to the Wemos' pins. I designed a simple circuit board for the sensor, with additional pins so it can be extended for future use. Unfortunately I wasn't paying attention to the conversion of mils and didn't make the mounting holes anywhere near large enough.
I still need to find some little boxes for them, for the most part they're just tucked into corners.
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The software is pretty straightforward. The boards run ESPHome with the stock pmsx003
integration. The only real customization is a sliding window moving average to reduce jitter.
sensor:
- platform: pmsx003
type: PMS5003T
pm_2_5:
name: "Office Emory Particulate Matter"
filters:
- sliding_window_moving_average:
window_size: 15
send_every: 15
temperature:
name: "Office Emory Temperature"
accuracy_decimals: 0
filters:
- sliding_window_moving_average:
window_size: 15
send_every: 15
humidity:
name: "Office Emory Humidity"
accuracy_decimals: 0
filters:
- sliding_window_moving_average:
window_size: 15
send_every: 15
I also have a handful of spares, so if you're interested I can send either a DIY kit or a fully assembled version.