A home sensor with Arduino, InfluxDB and Grafana

TL;DR: it was fun to build great graphs. But the battery did not last long, air quality is difficult to track.

the woden box

Above, the box with plywood. Because I do not have a 3d printer, and I like wood.


For the sensor box

  • ESP 8826, WEMOS D1
  • LCD 20x16
  • Humidity sensor DHT11
  • Air quality sensor MQ9
  • Red and Green LEDs, corresponding resistors

For the outside sensor

  • Old pickes glass jar, and glue or silicon to seal it.
  • ESP 8826, WEMOS D1
  • 11B12 Temperature sensor
  • Batteries AA, rechargeable (because environment)

the server side

  • Nginx, with full encryption and authentication for the
  • InfluxDB, for storing the datapoints
  • Grafana

the result

Nice graphs were plotted:

Lessons learned

If you cannot know why is not working, its hardware

Battery life is hard

  1. Air quality measurement with MQ sensor was disappointing. Maybe have to spend a bit more, or just learn how to calibrate it.
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