What is the difference between the TVOC IND30 and IND40 measurement on the dashboard?
I recently acquired a few DIY PRO 4.2 units with the SGP41 add-on sensor and couldn’t find any information about these two different measurements on the dashboard.
Cheers!
If you use the SGP41, the chemicals are measured as an index between 0 and 500 that is displayed as IND40. You can see in the spec sheet of the SGP41
The previous version of the Sensirion TVOC chip was the SGP30 that measured the chemicals in ppb. There is an official conversion formula from the SGP41 index to the SGP30’s ppb and this is seen in the IND30 column.
The conversion is described in this document:
Thank you! Perhaps this would be a useful reference in the FAQ?
the TLDR from the spec sheet: for the SGP41, TVOC:100 and NOX:1 is average.
@f3d - thanks for asking this question.
If you use the SGP41, the chemicals are measured as an index between 0 and 500 that is displayed as IND40. You can see in the spec sheet of the SGP41
@Achim_AirGradient - I got my DIY Pro kit 2-3 weeks ago and am quite happy with it – Thanks very much for making this available. The assembly instructions are really good, but I’d say the weak point in the kit/product is what to do once you start using it.
If there is a place where it is mentioned to turn on 'TVOC (Ind40)` with the optional SGP41, I missed it.
To expand on what @f3d said, it would be really helpful to have this information and the change be more prominent. I was searching for ind30 etc. to better understand my readings. At first I wasn’t finding much.
Also, in the dashboard Ind30 is a default and gets a severity bar next to it, but Ind40 doesn’t.
Agreed with the IND30 and IND40 points from above. The dashboard is not persistent. If you login either private, no cookies, clean browser you always need to reset what is shown and the defaults seem like they need some work.
Do you have an Outdoor monitor as well? For me, the gray line is an overlay of what my Outdoor unit was measuring at the same time
I do have an outdoor and verified that is the number showing for it on the grey line. Thanks for pointing it out something that I guess should have been intuitive and obvious that I simply didn’t connect the dots.
We are currently working on exactly this. There will be a lot more explanations directly integrated into the charts and other views.
I think should be available later this month.
