API Upload TVOX, NOx and PM reduction DIY Pro data with ESPHome

Software integrations
#1

Hello,

I just received my DIY Pro (pre-soldered) with the SGP41 TVOC module and everything is working fine.

I wanted to use it with Home Assistant / ESPHome and used this configuration file:

To add the TVOX and NOx data, I added the code from this site:

No problem on the Home Assistant side, I can see all the data.
But on Airgradient site, I can see that some data are missing:

  • TVOC (Ind40)
  • NOx (Ind41)
  • PM Reduction

For TVOC, however the TVOC (Ind30) data is correctly populated.
What should I do to upload the missing data to Airgradient site ?

Here is what I currently have in my ESPHome config file:

interval:
  - interval: 10s
    then:
      - display.page.show_next: oled
      - component.update: oled

  - interval: 5min
    # Send data to AirGradient API server
    # for more details have a look at sendToServer() function:
    # https://www.airgradient.com/open-airgradient/blog/airgradient-diy-pro-instructions/
    then:
      - http_request.post:
          # AirGradient URL with the last 3 bytes of the MAC address in Hex format all lower case
          url: !lambda |-
            return "http://hw.airgradient.com/sensors/airgradient:" + get_mac_address().substr(6,11) + "/measures";
          headers:
              Content-Type: application/json
          # "!lambda return to_string(id(pm2).state);" Converts sensor output from double to string
          json:
            wifi: id(airgradient_wifi_signal).state
            pm01: !lambda return to_string(id(pm_1_0).state);
            pm02: !lambda return to_string(id(pm_2_5).state);
            pm10: !lambda return to_string(id(pm_10_0).state);
            pm003_count: !lambda return to_string(id(pm_0_3um).state);
            rco2: !lambda return to_string(id(co2).state);
            atmp: !lambda return to_string(id(temp).state);
            rhum: !lambda return to_string(id(humidity).state);
            tvoc: !lambda return to_string(id(tvoc).state);
            nox: !lambda return to_string(id(nox).state);
          verify_ssl: false
#2

I’ve seen in other yaml config files that the JSON fields are tvoc_index and nox_index so perhaps try that change?

tvoc_index:: !lambda return to_string(id(tvoc).state);
nox_index: !lambda return to_string(id(nox).state);

Untested on my side though as I’m not having any luck getting any of my data up to the Airgradient site after reconfiguring with ESPHome (Home Assistant is fine).

Edit: Realised I was missing a DNS entry for my static IP. After fixing that the values for TVOC and NOX have populated on the AirGradient Dashboard with JSON as suggested above.

#3

Thanks @Andrew_Taylor , it works for “nox_index” which populates NOx (Ind41).
But it doesn’t work for “tvoc_index”.
However your “tvoc_index” was using the value tvoc behind, which was already captured by my “tvoc” which populates TVOC (Ind30):

tvoc: !lambda return to_string(id(tvoc).state);

So I didn’t really understand why I should send it again under the name “tvox_index”.

So @Achim_AirGradient , do you have perhaps an idea how I can upload values to TVOC (Ind40) and PM Reduction ?

Thanks !

#4

tvoc_index should work. What error code do you get back?

#5

Hello,
I don’t have any error, it is just that TVOC (Ind40) and PM Reduction are still empty on app.airgradient.com.
But what is the point of tvoc_index if we give it the same value as tvoc ?

tvoc: !lambda return to_string(id(tvoc).state);
tvoc_index:: !lambda return to_string(id(tvoc).state);
#6

tvoc is for the SGP30 sensor that we used before. The SGP30 sends values as ppb.

tvoc_index is for the SGP41 sensor that sends values as an index.

Reduction is a calculated value between the outside pm and the location. It is not something you can post on the api.

#7

Ok I have removed the tvoc line and only kept the tvox_index.
However I still only have TVOC (Ind30) which is diplaying values, what about TVOC (Ind41) ?
I am not even sure about the differences between the 2…
Thanks !

#8

There is a formula for calculating the TVOC_index into the old TVOC value which we use so that customers who purchased our monitor with the old TVOC sensor can make comparisons.

#9

So TVOC (Ind40) is of no use for new customers and I can ignore it ?
Edit: after correcting some error in my YAML file it seems to work now, TVOC (Ind30) and TVOC (Ind40) are correctly filled. Thanks !

#10

Is there an API reference document anywhere?