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Converting 120v motion sensor to run on 12v? Answered

HomeDepot sells a motion sensor for home security lighting with a 270* viewing angle for $22. I'd like to convert one of these units to run off of 12v, keeping the timing relay intact. Has anyone attempted this?


This has been 4 years ago... But did someone have instruction on where to write up the wire? Or next to which component?


8 years ago

I just saw a 12V - DC PIR Security Motion Sensor Spotlight on Ebay Item: 230498425865 The picture is here if you want to see it working, hope that will help someone :) http://yfrog.com/izdsc00741uzj

Transformers are used many times to lower AC voltage.  Then 4 diodes rectify it into DC.  However, sometimes transformers are not used at all.  In the case of my "Super Switch", a capacitor and resistor were used to lower the voltage.  After much thinking and recalling on the idea of "reactance" I finally got my remote controlled switch to run off 12voltsDC instead of having to have it connected to the wall 120volts  (to which i danced and shouted).  Tool Using Animal explains it here using LED's

Yes what he said. Where the power comes in there may be a small board which is the power supply, or it may be mounted right on the board. Check around on the board and measure. If it does have a built in power supply hook it up to that power rating, if it does not then get a 12vdc inverter to 120vac or build one as there are lots of schematic on the internet for them. Good Luck! = )

Can you get a look at the guts? odds are it has a transformer built in - where power goes thru a rectifier diode bridge, then a transformer, then a capacitor. If you see these components, measure the voltage on the other side (probably 12v - in a lot of electronics, although it may be 5v or 9v, or 24v as well) If it is 12v inside, just hook up the power there.