DC wire colors

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BillyK

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In my 77 Chris Craft the original DC wire colors are black - positive, white - negative. As you all know since then all DC wiring has been changed to red - positive, black - negative. I am rerouting and running new wires. Should I stay with the old white and black colors or change everything I touch to red and black? What makes the most sense.

Billy K.
 
Not to add to your confusion but marine wiring for DC negative is yellow now a days.
 
Whatever you do, the color code you follow must be consistent. Otherwise it is at best useless; at worst, dangerous.

If you are completely re-wiring, I would suggest ABYC standards. Here is a convenient table:

http://www.glen-l.com/weblettr/webletters-5/wl44-wiring.html

If you are only rewiring a portion, stick with whatever you have ( << shudder >> )
 
That original wire did not follow normal DC wiring colors. To my knowledge red has always, or at least for a very long time, been DC positive and until a few years ago black was DC ground. While black was AC hot.

I'd rewire it to the new standard of red DC pos. and yellow DC ground. No reason to repeat the old nonconforming wire color code now. If you are worried about confusing some one down the road put up a sign noting the wiring color issues.
 
I had known about yellow and green as grounds for LED lighting, but didn't know about it for DC. I was not given red and yellow as a choice from my electrical supplier, but I think it would really confuse things, considering.

Maybe I should stick with white and black and get used to it.

Billy K.
 
You could always put the correct color tape at the terminations. You could also use a wire labeler but they are pricey.
 
Are you sure you are not looking at the AC side? If DC , check to see if they used house wiring with solid conductors instead of stranded type needed to more safely resist vibration failure on boats.

Here's another marine DC color-code table like Radioactive's , on the Marinco/Ancor site.:
http://www.marinco.com/page/marinecolorcodes.

If any of the old or new wiring is at all ambiguous, I suggest you be sure to clearly label at both ends of each run. After testing to confirm.
 
It is definitely DC I am looking at, and consistent throughout the boat. I have confirmed the black is positive and white negative. It is a 37 year old boat that has had upgrades and add ons. Some of the work is good and some not so good. There are also some things that don't work correctly and I want to change all the lighting to DC LED. There is no way I want to change all the DC wiring, only what needs attention.

I was hoping someone else had run into this problem and what they had done about it. It maybe just easier to keep the colors black and white.

Thanks for the input,

Billy K.
 
Make absolutely sure your not looking at the ac side. And actually YES white and black were used for dc, and yours is correct for the usage of 2 wire dc grounded power system. You still see this a lot, especially in older boats.

Are you completely re-wiring the boat? If yes, then change it to the newest ABYC standards. If your not and only doing a small part, then no, leave it as it is and keep the same standard you have. This will stop confusion later down the road by you or someone else. What you have is acceptable the way it is, but changing to half this and half that would make it confusing at best, dangerous at worst...........D..........
 
Hi, D! Best to You and Yours!

I serviced channel markers with USCG for awhile and their DC systems were Black(+) and White(-).
 
Hey JD!!!! Same to you and the admiral. You herd I stepped up a bit with the new boat didn't you? Got a 33 footer now, fully loaded. Going to put her in the gulf in either the spring or fall, not sure yet, been running her up and down the tentom for the last couple months.

Yep, black and white is fully acceptable and is still in use. Some new dc lighting I just bought for mine were black and white, and the original wiring I connected to was, you guessed it, black and white.........D.........
 
The old, old DC wiring on boats use to be White (pos) and Black (neg).
After because the crosses with AC was changed to Red (pos)Black Neg.
I would suggest to go with the new code. Black or yellow for Neg and
Red for positive. Yes D. Andrews but they come marked as white wire with a tag saying + or pos.
 
About 10 years ago, I refurbished a 1980 Classic 24' cruiser. The DC wiring was black and white. At that time, I posted the same question on a different boating forum and on this forum. The answers I received were almost unanimous: To avoid any confusion, maintain the wiring code existing on the boat at present. That's the best route to go. Of course, any new equipment, such as a radio, GPS, fishfinder, etc. will have a different wiring code. Just connect the wires to power each correctly. Hy
 
quote:
Originally posted by boatcomfort

The old, old DC wiring on boats use to be White (pos) and Black (neg).
After because the crosses with AC was changed to Red (pos)Black Neg.
I would suggest to go with the new code. Black or yellow for Neg and
Red for positive. Yes D. Andrews but they come marked as white wire with a tag saying + or pos.

Click to expand...


Actually the didn't. The wires had no marking at all, but the paperwork that came with them did identify them. I did think it was strange that they were not tagged..........D......
 
I would not use black and white. It is confusing as white is normally AC neutral a,d black is normally DC negative or AC hot.

If you are going to rewire, go with what is used these days which red and yellow. That's what I m using on the sail boat I m building. For the existing stuff you were not planning on changing, you may want to consider replacing the easy to replace runs with new wires. Chances are your 70s vintage wires are not tinned anyway and may have increased resistance. For stuff that's too hard to reach or too long, then taping the ends with the proper color is acceptable.

On my 1970 hatt, the DC system is red and black, but not tinned, although the higher 32v helps reducing losses
 
Yellow has been the DC negative standard for a few years. To the best of my knowledge red has been the defacto DC hot.
I guess on some of the older boats white and black has been used for DC?
To me white/ black and green is best left for AC circuits.
I have seen green wire used for bonding.
When I rewired my 12VDC circuits I used red and yellow marine grade tinned wire.
Bill
 
For minor repairs and additions, I would keep whatever standard that is on your boat even though it is not today's standard. It would be way too confusing for DC hot to be black on one circuit and white on another.

If you're rewiring the boat, it makes sense to use today's standard and that means DC negative is yellow to avoid confusion with AC "hot".

If you're doing major work, but not a complete rewire, you can always color code the ends of wires and cables using colored tape or heat shrink to make everything conform to one standard.

Note that ABYC assigns different colors to different functions so not all DC positive conductors are the same color. You can get the colors on the Internet or in wiring books.
 
So this is what I've been tackling for the past few weeks and why I posted here. you guys have been through more of this then I have. It would be near impossible to rewire everything and taping existing wires in these closets would take more time than I want to put into it. I've got most everything traced out in the aft head and stateroom. It would be easy to change any new wiring to red and yellow. I can tape all ends no problem. I will have no problem with future repairs or additions. What I'm worried about is the next guy. If I leave the closets black and white, and ends red and yellow, is that going to be clear for future repairmen?

Thanks for your advise,

Billy K.

Overview of lower helm area

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Side by side

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Side by side

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Close up cabinet next to panel

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Close up cabinet behind panel

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Close up of the back of the panel

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If you are only rewiring a portion, stick with whatever ( color code scheme ) you have. Mixing coding systems is the same ( or worse ) as having no system at all.

Order of preference ( applies to entire boat wiring system ):

Use the current standardized code. ( over the entire system )
Use the original, existing, color code system ( over the entire system )
Mixing systems is NOT recommended.

IMHO.
 
That's what I suggested and what I did when I refurbished that 1980 cruiser: Follow the color code there unless you intend to rewire everything. Looking at your photos tells me that rewiring everything is a gigantic job and one you're not ready to try. It's not worth the effort. If you're worried about a future owner, attached a label on the inside of every wiring cabinet stating the wiring code in use. You can seal each to a door or panel with clear packing tape. The next owner(s) will then know how to proceed. Hy
 
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