How do I power 12v trailer lights with 24v system?

[mrgerke81]

I just bought a deuce. I want to install a hitch to tow a trailer. The one issue I have is how to correctly hook up a trailer wire connection. How do I get the 24v signals coming off brake lights, turn signals, running lights etc. to run a 12v system on a trailer. The goal is to be able to hook up to different trailers and not have to worry about switching out bulbs on the trailer or anything like that to make it work. Is there a way to create a relay system with current 24v system and have seperate 12v system for trailer lights?

 

[Westech]

well the military has some sort of controller box on there 40 foot tri axle trailers. you just hook up the plug and flip a switch.... could get one of the converter boxes.. prob have to buy a trailer to get that part.

 

[Floridianson]

Call RadioShack and tell the what you are doing and you need a resistor. In this case you will need three I believe one for each line. If it was me I would make a removal link that could be used on any 12V trailer.

 

[newt]

I found this site.

http://www.gumpydog.com/bus/MC9_WIP/Electrical/Tail_Light_Converter/tail_light_converter.htm

 

[Floridianson]

Well forget my idea went on line and was enlightened.

 

[dlawbrey]

NAPA sells lights that operate at 10-30volts so they will work at either voltage. I do not have the part # with me but will try to remember to get the part # tomorrow when I am at work. We just did this change on one of our trailers. Only modification that we made was adding a trailer plug to the end of our original military cable that was compatible to our trailer. Nothing to it.

 

[bottleworks]

See: http://www.steelsoldiers.com/index.php?name=PNphpBB2&file=viewtopic&t=21998

 

[nattieleather]

Get a voltage regulator IC from radio shack. They are usually thre wire with one being voltage in 24V one being voltage out 12v and one being the common ground. Wire it in line and away you go. Something to remember. Most vehicles run hotter than the standard. MV run 28V and civy vehicles run 14V...that and filiment light bulbs can take a lot of abuse before they blow. I know you can hook a 12v trailer to a 24v truck....your bulbs are just really bright!...

 

[Blood_of_Tyrants]

Wire them up in series. Power to one bulb then to the next bulb and to ground.

 

[papakb]

Gentlemen,

There's no easy way to put the bulbs in series in most vehicles because to do so you'd have to remove the ground from one socket so it could "float". Likewise to add voltage regulators is impractical because you'd have to have one pair for the brake lamps and one pair for the turn lamps and another pair for the running lights. Adding resistors will also work but again you have to add a resistor for each lamp, not just one of them. Following Ohms Law the formula is E = IR. So to drop 12 volts in a circuit running 1 amp (like a lamp) you need a 12 ohm resisitor. The kicker is that you also have to figure in power using the formula P = IE. That means you need at least a 12 ohm, 12 watt resistor per lamp.

All this can be done but put all this science crap aside and invest in some LED lamps that will operate from 10 - 30 volts and be done with it. They'll operate on anything over 10 volts that you feed them. This way you can worry about how your going to get from that military trailer plug into that civy lamp socket on your Tahoe...............

Kurt

 

[RodUSMC1962]

I pull s 16 ft civi trailer with my duece and all I did was put 24 volt bulbs in it . If I pull it with my chevy pick up I leave the 24 volt bulbs in and they work fine.