What colour wires do I want ?

**Boo2** · 20-02-12, 00:35

Hi,

I've got a few wiring projects lined up and some of them require 3-core wire. I don't want to buy actual 3-core because it's more economical to buy reels of single core and make it up with heatshrink ties along its length.

My question is what colour do I want in addition to the red and black I definitely need ? The wire will be used in applications with multiple positives like auto/manual bilge pumps and tricolour nav lights. To be more specific I am asking if there is any kind of standard in use ?

Thanks,

Boo2

**prv** · 20-02-12, 08:50

For what it's worth, the three core I used for my bilge switch was red, black, and green. Seems logical to me for the "other positive" to be the opposite colour to the normal positive.

I'm not aware of a standard.

Pete

**nigelmercier** · 20-02-12, 09:54

Originally Posted by Boo2

I am asking if there is any kind of standard in use...

On my boat, many of the manufacturer's ground wires are blue, and all the lighting positives are white. You can invent your own colour code with coloured heat-shrink or markers on the ends.

**Ruffles** · 20-02-12, 15:20

My tricolour seems to have been wired with American mains cable. White, black and green. Quite a neat idea really as presumably it is cheap. And the conductors are tinned!

**Ocean Safari** · 20-02-12, 20:06

Originally Posted by Boo2

Hi,

I've got a few wiring projects lined up and some of them require 3-core wire. I don't want to buy actual 3-core because it's more economical to buy reels of single core and make it up with heatshrink ties along its length.

My question is what colour do I want in addition to the red and black I definitely need ? The wire will be used in applications with multiple positives like auto/manual bilge pumps and tricolour nav lights. To be more specific I am asking if there is any kind of standard in use ?

Thanks,

Boo2

I would have thought all +Ve would be red, 0V black and -Ve blue.

Cores should have cable ID's, if like this you would know what voltage to expect when investigating any problems with a meter.

**William_H** · 21-02-12, 00:21

So clearly there is no standard. However most would agree that red is +ve black is -ve. You could then resort to the 3phase AC code of red,blue and yellow or white for different kinds of +ve. So you make up your own code good luck olewill

**dhippey** · 21-02-12, 00:56

Whatever system you use be sure to document it with some kind of wiring diagram for if/when it goes wrong :-( or when you want to add some new techy toy :-)

Regards,
David H.
http://www.eventoftheyear.co.uk

**Ocean Safari** · 21-02-12, 10:54

Standard normally used in UK for DC is: positive volt with ref to 0V - RED

0 Volts - Black

negative volts with ref to 0V - Blue

+ve 12Volts Red and Black
-ve 12Volts Blue and Black (black being 0Volts)

**colind3782** · 21-02-12, 11:27

There can be an issue with red and green as it's the most common form of colour blindness and some people don't even know they have it as it's more pronounced in certain low light conditions. So mixing red and green cables may not be such a great idea.