Interested in thinking about things that can happen in demoing/using a simple air sensor.
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Wow, I wouldn't have guessed that it'd show green with low power (i.e. no reading from the sensor, i'd imagine), so hearing that it turned white instead is really helpful. I wonder if we should generally say "if you see it turn white, that's an error"?
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I haven't seen this happen in part because it runs a /long/ time on a battery, but I have seen it when running on a solar panel without enough sunlight. It would fail and reboot every second or so, so the light would blink.
Recently we changed the firmware so that it waits 2-3 seconds to start up. The idea was that it'd try to run for 2-3 seconds, before turning the light on, so that it could "test" whether there's enough power. And if there was, it'd start showing a light. Otherwise, it'd just stay dark (although you may see some of the really tiny lights blinking as it boots up).
That way, if power is too low, it wouldn't annoyingly blink a lot, but rather would reboot over and over but never get to the point where the light goes on. We're still testing how well this works.
Thanks @Warren (and @Stevie) for this info. Recently I fully charged the battery bar but after plugging in the "traffic light" sensor, the display stayed white even with high generated PM2.5 levels.
Your ability to create a light and small Plantronics sensor-battery combination is nonetheless very interesting: if the sensor could also write data to an SD card (as it does in PurpleAir SD models), I would like to know how much this all weighs and contact my two drone pilot colleagues. If feasible, I think it would be fascinating to measure PM levels at different altitudes and positions relative to a frac sand mine.
Hi, @crispinpierce - can you check that the white connecter is fully inserted? I noticed the white light happens also when that cable comes loose. If that still doesn't work, please post a photo and we can help you debug or we can swap you for a new one.
We can add an SD card logger for about $15, i believe. It does add complexity and some weight, although nowhere near the weight of the battery, which is the main contributor to weight.
Hi @Warren, Thanks so much for the quick follow up. Here are photos of the unit fully plugged together, showing white after several minutes of warm up (was expecting green) and after corn starch particulate generation (was expecting red).
(I'm not sure if images are uploading after drag-and-drop.)
I would be VERY interested in a Plantronics/battery bar/SD card unit we could load on a drone (if the SD card portion were lighter than the battery bar, I'm sure this can work). We can certainly afford the cost you suggest.