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Wire color in Recreational Vehicles

Posted: Wed May 01, 2013 7:52 pm
by Dave Thacker
I'm not sure if this standard has changed or remains the same. I own a 66 Airstream and like Techman2015's video:

http://youtu.be/nAUExEovzlE

...like Techman2015's video, mine also uses a black wire for positive. Just working it out logically, measurements show (in my camper) that there is no dedicated negative wire. They put ground on the white wire. I also have a ground in my romex and normally the ground and white are bonded (connected) together as they are in my camper. So, in the spirit of cheapness, they don't have to run a ground wire for the DC if they do this, there are no issues (that I've detected) with this setup other than making it weird to hook things up. Normally in DC powered devices, ground is always black or green and positive is usually red or whatever the lightest color is. It seems to me that in keeping with the education of the trailer builders, they are using an extra black wire for 12V which is considered "hot" just as there is a hot wire in the 110v AC system. You cannot mix the 12v DC with the hot side of the AC circuit. It is always a separate wire. It's a bit confusing, but I thought I would throw up what seems like the most likely explanation of why they use black for positive in an RV. If I were building an RV, I'd use red and tag the wire every so often. I'd also include a note in the DC breaker box indicating the wire colors. It's an important principle of safety to leave things so another mechanic and follow along.

Happy Connecting!
Dave Thacker
Radicalrc.com

Re: Wire color in Recreational Vehicles

Posted: Mon May 06, 2013 6:56 pm
by techman
Yeah, seems to make sense.

Although why anyone goes away from the standard really does not make sense.

My truck camper also has some green wires in it for some odd reason. And my stupid large camper switches to white and yellow for the running lights. I mean, come on, lets keep some sort of standard.

Re: Wire color in Recreational Vehicles

Posted: Tue Nov 12, 2013 7:08 am
by mr bugsier5
ha ha ,you wont believe wat i run into at some jobs!, all colors of the rainbow, try to find a fould than, ha ha , mostly spéaker cable , or wires we normally use here in home installations, all massive wires etc, totaly not for use in boats! :)

when i'm ready repairing , and making it good need and safe, mostly with les wire's and cables as before, LOL, in the bill it's mostly labor, and no materials, other than ty raps and connection strips.ha ha ;)

i'm used to that, all in a days work ha ha ha ! :lol:

all my clients are happy to see me! (not only gowing away after job!) lol :lol:

Re: Wire color in Recreational Vehicles

Posted: Sat Nov 30, 2013 1:15 pm
by techman
Yeah, I wonder what they are thinking sometimes. Or not thinking maybe.

Re: Wire color in Recreational Vehicles

Posted: Mon May 12, 2014 11:45 am
by Zelturo
Iam an RV tech and I can tell you one thing in the RV bussness there is no standard in color wire, I have personnaly seen:

White : negative, Black: positive
Green: positive Black: negative
Red: positive Black: negative
anyway you see where Iam going with this

The best way to go is like this:

If you have a fuse or a resetable breaker on a wire it means that its the positive. Also if you have one wire that is connected on the frame its negative. If those two way dont work take a continuity reading beetween the frame and the wire you have in the front and you can that way figure wich wire is ground.

You guys should also make shure you have only one wire that connect to the positive I have seen system that have multiple positive.

Take care David

Re: Wire color in Recreational Vehicles

Posted: Thu May 15, 2014 1:10 pm
by mr bugsier5
most yachts and rv's and campers the wiring is always a mess! :lol: :mrgreen: even new build boats! :roll:

i always mesure first before i connect something , most cases red shoud be positive here , but you wont believe the things i find somethimes! :lol: :lol:

Re: Wire color in Recreational Vehicles

Posted: Wed Jun 04, 2014 9:53 am
by techman
I know what you mean. MY truck camper had green, white and yellow wires all throughout.

My old 32 foot camper has yellow, white and black wires.

My RV has white and black.

What a mess. No standards.

When I built my tiny home I will use standard colors for AC wiring. I will use red and black for DC wiring. No more confusion here for me.