Is it possible to add a light sensor to a ruuvi tag?

Hi all, I just ordered a pack of 3 ruuvi tags, I have no experience yet about them so my question may be pretty stupid. I was wondering if I can ‘hack’ a ruuvi tag so that I can add a light sensor to it? Maybe by swapping out the motion sensor? of course I’d need to buy I small light sensor somewhere and attach it to the pins, but is such a thing feasible?


We’ve been considering adding a SMT photodiode / phototransistor to ADC pin and using ADC pull-ups, for example

but we haven’t had a chance to try it out or even simulate it just yet.

Thanks Otso. I guess I’ll wait till somebody has a done it already, don’t have the time to experiment with such things unfortunately.

A lot of energy-meters/electrical panels have a flashing LED that flashes 1000 pulses per kWh of energy used.

Would it be feasible to use a ruuvitag with a light-sensor to count these pulses?

I’m guessing the ruuvitag can’t be put to sleep very much in this kind of application, if it’s going to be capable of counting at e.g. 10 kpulses/hour or more? But in an electrical panel there would be 230VAC available to power the ruuvitag.

If the electronics and mechanics were designed so that light pulse would trigger digital interrupt it would be feasible. I think the ADC support continuous sampling and level interrupts which might also be a “good enough” solution, even if current draw would be a higher than a custom solution.

I guess there are already quite many wireless solutions available for measuring energy meters?

Great :slight_smile: - any links to one that costs about the same as a ruuviTag and outputs on BLE or WiFi on some open protocol so that I can collect the data with e.g. ruuvicollector + Pi3 setup?