CCS811 Air Quality Sensor and ESPeasy

[-manuel-]

Hello all
I installed Atom and PlatformIO but I wasn't able to compile an own build with plugin for CCS811 (P090). I realized then, that the sensor CCS811 might be supported in testing build according to the plugin list.

https://www.letscontrolit.com/wiki/inde ... lugin_list

I then installed ESP_Easy_mega_20201130_test_beta_ESP8266_4M1M and I was able to select CCS811 from the device list. I connected the sensor to esp8266 according to:

ESP8266 --> CCS811
G --> GND
3V --> VCC
SDA --> D2 (GPIO-4)
SCL --> D1 (GPIO-5)

Unfortunately I don't get any data from the sensor.

CCS881.png (13.83 KiB) Viewed 2355 times

Did I miss something? Thank you very much again to point me in the right direction.

Greetings Manuel

[TD-er]

Does the I2C address of the sensor show up in an I2C scan?

[-manuel-]

Hello TD-er
Once again many thank for your help. This is really very kind. I always forgot the I2C scan under tools. Scanning doesn't find any device either on 0x5A nor on 0x5B but I changed the settings and enabled "Force Slow I2C speed" and suddenly I had TVOC: 0.0 and eCO2: 400.0.

CCS881_new.png (10.33 KiB) Viewed 2334 times

Logging Info was showing some changing values with "Take reading every: 1 seconds" and also if it is set to 10 seconds.

Logging2.png (89.9 KiB) Viewed 2334 times

I have my sensor right next to my notebook in the living-room. Does this make sense with these values? I don't know if they are reliable. TVOC always stays on 0 or it changes to 1 or 2 and goes back to 0. Both values seem to be very volatile.

Thank you for your answer.

Greetings Manuel

[TD-er]

Well the CCS811 isn't a true CO2 sensor.
It is measuring a number of volatile organic gasses and by the ratio (and concentration) of those, it computes some value which the named "eCO2".

The values reported by that sensor also fluctuate a lot.
Just set it to update once a second and blow at it.
You should see it spike for a short while.

I don't think you can use the sensor to measure the true CO2 concentration in the room.
For that you really need a true CO2 sensor like the MH-Z19 or the SenseAir S8 or S11 (Sunrise).

The MH-Z19 does also have its quirks, but at least it does measure the CO2 concentration instead of estimating it based on a lot of other gasses which in some situations also show some relation to the CO2 value in a room.