MultiNav Pro+ sensors module - air quality sensor, what gas/particles does it actually detect?

@John Martinez good question, and yeah it totally matters for what you can actually claim in your data output.

 

Honest answer: I don't have the exact IC part number for the air quality sensor on the Sensors Module in front of me right now, so I don't want to guess and steer you wrong on something this specific. The difference between a VOC/eCO2 proxy sensor (like a CCS811 or SGP30 style) and actual PM2.5 particulate detection is massive for reporting purposes — one gives you a derived index, the other gives you real particle mass concentration data.

 

What I'd suggest is either checking the Resources section in RFOXiA Club where the hardware documentation lives, or posting this directly to Moamen — he's the one who designed the board and will know exactly what IC is on there and what the raw output actually represents. For a monitoring node going into the data network especially, you want that clarity before you build your reporting layer around it.

 

If you do find out the part number, drop it back here — would be useful for others building similar nodes.

From what I've dug into with the sensors module, the air quality sensor is a VOC-based sensor (think SGP-type) that outputs an eCO2 and TVOC reading - so it's more of a proxy/index measurement derived from volatile organic compounds rather than a true CO2 sensor or a particulate counter. If you need actual PM2.5/PM10 you'd want to pair it with something like a PMS5003 on a spare UART, because the built-in sensor won't give you that. Might be worth double-checking the specific IC on the module if you can find the schematic, I've seen a couple hardware revisions floating around that might use slightly different parts.

Jennifer's spot on - it's VOC-based so you're getting eCO2/TVOC as derived values, not a real gas analyzer or particle counter. For outdoor env monitoring you'll almost definitely want to bolt on a proper PM sensor, the PMS5003 is solid and plays nice on UART but the Sensirion SPS30 is worth a look too if you want I2C and better longevity outdoors.

Good shout on the SPS30 Michael, been running one on an outdoor node for about 8 months now and it's held up way better than I expected - the SEN5x series from Sensirion is also worth a look if you want VOC + particulate in one package and don't mind spending a bit more, could simplify your build since you'd essentially be replacing the onboard air quality sensor's job and adding PM in one shot.