Light Level / intensity Sensor


#1

Hi,

I have been thinking that I would like to add a external light intensity sensor to one of my ruuvitag. I’m using now default firmware and ruuvicollector so I need to modify those but my question is, why kind of sensor i can connect? Would this work https://www.addicore.com/BH1750FVI-p/ad290.htm ? Can I still use internal sensors if i add the intensity sensor?

Thx
Mika


#2

You can solder the sensor to the test points on the bottom of RuuviTag with some wire. You can keep on using the sensors onboard RuuviTag, but you’ll have to code the support for your sensor


#3

Both phototransistors and CdS LDRs have significant sensitivity variation with temperature, which could make reliable detection of small light intensity changes difficult. CdS cells also have memory effects which can be very significant, as well as aging effects.


#4

CdS also tend to not be RoHS-compatible. In most use cases we’ve heard about the light sensor would be used to detect “box is open/closed” or “night/day” -types of changes, rather than any precise lux levels