PMS7003 dust sensor battery powered

[rozpruwacz]

Hi,

I'm trying to build dust sensor node powered with li-ion battery. Actually I already built it, but i'm not satisfied with how long it runs on battery. The problem is that according to the specification, the PMS7003 needs about 30 seconds after wakeup to give realiable results, and during this 30 seconds the node is consuming around 80mA of current which is a lot. I'm taking measurements every 10minues so according to my calculations the mean current is around 4mA. Between measurements I disable power for the PMS7003.
So my question is: are there other scenarios for using PMS7003 with battery that would make the node run longer on single recharge ?

[Nca78]

Hello @rozpruwacz, no there is no better solution...
All the precision lies with the regularity of the air flow and you need to make sure the fan speed is stabilized. But probably you can measure before that, make some tests.
Also, 80mA is the peak consumption when it lights up the led, but in real life I have less than that as peak (a bit over 60mA), and only for a short time, while most of the time it's way lower. So you can at least cut you average in half, and probably fan speed will be stable (or at least, stable enough for a decent precision) before the 30s seconds so you can save more.
But to use that sensor on battery you have no choice but to use a good 18650 or 26650 if you want it to survive for at least a month at 1 measurement/mn.

[alexsh1]

What Chinese are doing with this sensor which is used in a handheld air quality meters like this:

https://a.aliexpress.com/_UCY55

is this -> Li-Ion battery 3000-4000mAh
This would last hours. Not days.

Unless you want to use a car battery, I do not think there is a portable pm25 monitor able to work days without recharging.