12v receptacle wiring

[rhltechie]

I ordered a few 12v receptacles the other day and they came in today. i am really confused, or maybe i just dont understand how 12v receptacles are are wired. This is what the unit came to me looking like:



It also came with a white wire with a spade plug and an exposed end.



What in the world is the white they sent me? for ground? there is a little loop sticking up on a blade that looks like it would be for a ground. can someone help me out? did i order the wrong thing?

thanks

[Dale M.]

NO you probably did not order wrong thing....

Typically a cigarette lighter/accessory socket is wired with +12 volt wired to center stud/nut .... The white wire (jumper) is to connect the ground side of socket (shell) to any sheet metal in structure or chassis that is grounded to battery if chassis is use as ground conductor and/or socket is mounted in plastic or some other insulator....

IF you are unsure of mounting surface (grounded-not grounded) just run a "ground" wire (- negative side of battery) to the "push-on" blade terminal on "shell" of socket....

Dale

[rhltechie]

ok...thanks for that. thats what i was thinking but i was really confused that they had sent me a white ground wire. so basically i just run my positive to the nut portion and my ground to the spade/blade deal.

makes perfect sense..NOW

thanks again

[BPFox]

Mandy, it can be confusing with 12 volts because the "ground" or negative wire tends to change color. It should be noted that the positive wire also changes color. At the battery the main cables are usually red for positive and black for negative. Once the power leaves the fuse panel, the color of the wires change to identify function. An example of this can be found in your trailer wire harness where the negative wire, or ground is typically white. Yellow is the left turn and brake light wire, green is the right turn and brake light wire and brown is the running/parking light wire.

The good news is, you can create your own color code because electricity is color blind. It helps to use common color codes. When I wire my trailer the white wire will be used for 12 volt circuits being fed by the Tow Vehicle's electrical system. The trailer's system will be separate and use black to carry the negative side of the circuit. That's my choice, you, of course, can set yours up any way you want. Peace.

[wlooper89]

I believe most RV's use black insulated wire for positive and white for negative. For example the # 10 trailer brake wire I purchased from an RV dealer had black and white insulated wires inside an outer jacket. My 12V porch lights from an RV parts supplier also came with black positive and white negative pigtails.

However a lot of 12V things use red positive and black negative. Some jacketed # 10 wire I ordered from a solar power supply company came with black and red inside the jacket. So it can be confusing. In one case black is positive and in another black is negative.

One forum member who is an RV service professional said in another thread that the black positive and white negative wires are standard for the RV industry. For that reason I decided to go with black positive, white negative. These colors are also available at Home Depot in stranded, unjacketed #12 and #14 wire sizes.

But I also agree with BPFox that when building our own trailers we can set our own wire color scheme if desired.

Then there is trailer tail light and running light wiring. A whole other story and the colors vary between 4 wire and 7 wire hookup from tow car to trailer. I got into that converting my Little Guy four wire arrangement to seven so it would include a trailer battery charge wire.

Bill

[BPFox]

Then there is trailer tail light and running light wiring. A whole other story and the colors vary between 4 wire and 7 wire hookup from tow car to trailer. I got into that converting my Little Guy four wire arrangement to seven so it would include a trailer battery charge wire.

Bill

I guess this is a good example of my main point. If the folks in the business can't come together on a common code, why should we worry. I have never understood the thinking of those folks who came up with the wiring pattern for the 7 pin rv plug. As long as I live I will never understand why I have to attach my yellow (left turn) to the screw marked "red" or why the brown running light wire gets attached to the "green" screw. You also have to hook the green wire to the "brown" screw, these folks have a screw loose if you ask me.

[Russ in California]

Having been in the auto industry(parts) for many years, I think I'm inclined to go Red positive and Black negative. At least it's something I recognize.
There you go...

[wlooper89]

Hi rhltechie,

By accident I came across this post about RV 12V wire colors in a thread called "Wiring for lights". It may help to explain the presence of the white pigtail with spade connector for your 12V receptacle. This is a copy of the post by a forum member who is a RV technician:

Actually it is in the RVIA code to use the black/positive and white/neg for electrical systems when both AC and DC systems are present in an RV. I guess they figure it will be less confusing for the techs who work on them.
I come from a background of automotive and equipment repair, so is is confusing for me, I always thought red was positive and black negative Now I are a RV tech and have to relearn things

The web address of the thread in which this post appears is:

http://tnttt.com/viewto ... c&start=15

Regards, Bill

[bobhenry]

Holy Cow I did something right ! White was the ground color on my 4 way flat so I used the same white as ground for my 12 volt negative. It just made sense to me to keep a color doing the same function throughout the rig.

Had I had brown I would have used it as the 12 volt positive however I had black so I used it as the positive run.