I have an idea for a hack I'd like to build, but I need some help figuring out the right transformer. Let me know if there's a better place to post this sort of request.
I have some exterior LED path lights that work on 4 C-Cell batteries each. There are 6 of them, so having to replace the batteries is relatively expensive and a bit of a pain. Looking at the lights, I see that I could easily solder wires to the battery contacts and replace the batteries with a transformer. I could run a low voltage wire indoors to a transformer and never have to worry about batteries again. My problem is that I'm not sure what transformer to get.
I did some simple math but I have no electronics background, so I would appreciate getting guidance from folks that have more knowledge about this stuff.
Here's what I know:
Each light takes 4 C-cell batteries in line. That is they are stacked one on top of the other with positive terminal touching negative. I think that means I'd need to add the voltages together meaning 4 x 1.5V = 6V required.
I have no idea how much power each light draws (specs don't say anywhere) and the math I did doesn't seem to make sense. I know that alkaline batteries are normally rated for about 8000 mAh. The manufacturer of the light claims that the lights last about 50 hours before needing the batteries replaced. 8000 / 50 = 160 mAh draw. That seems really low to me. Is 160 mAh a reasonable amount for an LED light (supposedly 80 lumens output if that helps)?
So if I multiply that out 6 * 160 = 960 mAh required. I want to be able to add a few lights so let's double that (so just under 2A).
Does that mean I need a 6V transformer that can do 2 amps? That seems really low to me, so I'm hoping someone with electronics knowledge can provide some help figuring out what I really need.
Any guidance or nudges in the right direction would be greatly appreciated.