thestoloffs wrote:
Jim, you keep going back to your same idea -- which 2 pages of responses have told you that it's unrealistic for several reasons (which I'll summarize):
1. RV lights run off the 12VDC side of the house, but aren't usually stable enough to be reduced down to 5VDC to meet USB specs.
2. Most lights are mounted overhead, which isn't a safe place to have charging cords hanging from (snagging while sleeping, accidental choking, etc.).
Go with Dutch's or Roy's suggestions; they're workable without the safety hazards. But, don't hold your breath for the lights! Wanting won't make it so.
Reason #1 is hardly valid. You would need to have an appropriate 5V voltage regulator (usually a buck regulator these days, though a linear one would also work albeit considerably less efficiently). So long as the house 12V supply is somewhere between, say, 6.5V and whatever the regulator's maximum input voltage is, you can get plenty clean enough 5V power out. That's exactly what the little lighter plug chargers or the various other USB port chargers for car use that have been posted work.
If the hypothetical light were to have a wall switch controlling it, you naturally could not charge when that switch was off as there would be no power available.
