I have a enclosed trailer with a side door on it. The switch for the interior lights is up by the side door. I want to put another switch at the back door, coming off the aux power wire and then into the lights just like the front switch. My question is if both of these switched are turned on at once will it still be 12v on the lights or will it be 24v and blow the bulbs?

 

NOPE!!! Pretty hard to get 24v from one 12v battery.

 

What you need is a pair of three way switches, one at each door. That way the lights can be turned on or off with either switch.
If your trailer is like mine then the light switches are standard household type. Three way switches are the same size and fit the same box as a single pole switch and you can buy them at a Lowes, Home Depot, or a hardware store. Usually the information that comes with them explains how to hook them up. The travellers are connected together and the third terminal is connected to the power and the load.

Hyspeed

 

Both right! My trailer also has the 3 way switches but they aren't household ones, it's great because you can turn the lights on or off from the side door or the rear ramp, it's worth a few more bucks.

 

Ok thanks I thought so, just wanted to make sure. The switch in there is a 12v one, and I have never seen a 12v 3 way switch, have you guys?

 

Got that air on this evening Fiver 26* here

 

NOPE. Doors open and enjoying 72 degrees. Been out on the patio most of the day working with the computer out there. Absolutely gorgeous. Big full moon tonight and about 66 degrees right now at 9 pm. This is what it is all about down here - - these seven months are great - - two more are marginal - - then other three are great also, somewhere else.

 

Yes, I have them in my trailer.

 

All the three way switch is is a single pole double throw switch. In other words it has one common terminal and one open normally open terminal and one normally closed terminal. Look here (scroll down) and it will explain it better: SWITCH INFO
Tom

 

So how would I wire it to work so either switch can turn them on and off?

 

I would go to a trailer shop and find out because the difference between AC and DC is AC has a hot wire and a return common wire where as DC has only one hot. So for a three way switch to work correctly for a DC system then there has to be a difference in wiring from an AC setup. But again any good trailer shop must have a tech that knows how to install a switch they sell.

 

The wiring will be basically the same. The only difference is the neutral. AC uses a wire for the neutral and DC will use the body/frame as the neutral.
Tom

 

Quit your bragging or I will drive down there and haul your sorry butt up here and stick it in the snow.

DragginBob'sButtCasey

 

You're nothin but all talk. You drag your sorry butt down here - - and you will stay here and think you died and went to heaven.

AngelBob

 

YOU TELL HIM CASEY!!! right now it is 10*