Re: Reducing 18 volt DC to 12 volt DC

On 29 Jan 2007 17:53:55 -0800, georgevans@xxxxxxxxxxx wrote:

I have a cargo trailer that the lights work only when the parking
lights are onin my truck. This is problematic seeing as we are in and
out of the trailer all day. I am a contractor that uses 18 volt
Dewalt tools and therefore I own many batteries. We broke open an 18
volt flashlight and wired 4 12 overhead lights to it and find the
lights to be very bright and in addition they burn out the battery in
less than 20 minutes.? What to do? Can I limit the volts? Will that
extend the battery life? Lower the light amps? Phone a friend?
50/50? Ahhh! I thought I was so clever. Not so much. Any help??

If you put pairs of lights in series, across the 18 volts, you'd get 9
volts per lamp, which might be bright enough... try it. The lower
current will extend battery life, about double what you're seeing now.

If you put two batteries in series, that's 36 volts, which is right to
power *three* 12 volt bulbs wired in series.

But little batteries like this won't last long with a heap of lights
attached. Why not use a car battery?

John

.

Relevant Pages

  • Re: Reducing 18 volt DC to 12 volt DC
    ... lights are onin my truck. ... Can I limit the volts? ... extend the battery life? ... batteries are created equal with regards to their discharge patterns and ...
    (sci.electronics.basics)
  • Solar-recharging garden lights - rewire to mains?
    ... I bought three sets of Christmas lights for my garden. ... Each battery box contains three Ni-Mh AA ... Can anyone advise what is the correct voltage and ampage ... Do I still need to supply 4.5 volts, ...
    (sci.electronics.basics)
  • Re: 380sl Completely Dead
    ... The battery has 12+ volts, the lights are bright, and the voltage ... Starter Relay? ...
    (alt.auto.mercedes)
  • Re: HELP With Step-Down Transformer and Converter
    ... 12 Volt Cylindrical Battery, looks like a big AAA Batery ... Where do I put the Switch, Shunt and Millivoltmeter in the diagram ... circuit ON/OFF at precise time. ... Just turn off the 240 volts to the primary of the transformer when you're ...
    (sci.electronics.design)
  • Re: 12v TV
    ... what was being pointed out is that the mains power supply outpts 12 volts... ... hence the TV's components are made using the lowest tollerance parts available, no need to use more expensive higher voltage parts when the TV will never see more than 12.3 volts. ... as a fair few people found out tho, plugging it into the caravans battery directly... ... i have a large solar array on my vans roof, and it does an equalizing charge every month, takes the batteries upto 16 volts for a few hours to balance them all out and stir up the cells, my Tv would have let the magic smoke out first time it did that for sure. ...
    (uk.rec.caravanning)