Wire color???

[Sean]

Is there a standard for wire color for the 12 house system? ...

In the US, there is no standard color scheme for low voltage (below 30 volts, nominal) wiring in a vehicle.

For battery cables, Red is usually positive and Black is usually negative, but for individual circuits it is all over the map.

I prefer the DIN/TUV standard for low voltage ground, which is light brown.  While there is nothing wrong with black, as has already been noted, it is used for hot on the high voltage side, and choosing a different ground color can avoid confusion.  For the same reason, green would be an acceptable choice for ground wires, but many vehicle manufacturers use green as a hot lead for many circuits.

In the boat world, there is actually a standard and it is set specifically to avoid confusion with high voltage circuits, which, on boats, are often run in the same chases and panels.  When a high-voltage system is present with black hot wires, then Yellow is the preferred choice for low voltage ground return leads.

...   AC voltage must be lightest color for common but not white if a green is present.   Remember white is not a color.

This is just plain incorrect and is dangerous advice.  Neutral wires, confusingly known in the code as the "grounded" conductor, must be WHITE in all cases.  The code makes no exceptions here, although wires over a certain diameter may be marked with white tape at the ends rather than continuously white. For everything we would use in a bus, they must be covered with continuous white insulation.

On molded appliance cord (as opposed to built-in wiring), also known as "zip cord," BTW, the grounded (neutral) wire must always be specially marked; most manufacturers mold a rib or ribs into the neutral for this purpose.

Safety ground, known in the code as the "grounding" conductor, MUST be either bare copper, green, or green with yellow stripe.  Again, no exceptions until you get into very large diameters, where again end-marking with green tape is permitted.

Technically, by the way, white is a color, or, more precisely, a range of colors which, for transmitted light, is characterized by a parameter known as "color temperature."  It can be argued that pure black, however, is not a color.

For the purposes of wiring standards and codes, both black and white are called colors.

-Sean
http://OurOdyssey.BlogSpot.com

[Len Silva]

Minor disagreement Sean, 200-6 (in my very old book) says white or natural gray.  I have seen situations where both were used in order to identify two different neutrals.  This was in a situation where a multi lamp fixture was fed from two different circuits for low level and high level lighting.

[JackConrad]

   As was mentioned, low voltage wire colors are all over the map. Standard trailer light wiring is white for ground, brown for tail lights and yellow & green for turn signals
   I quess the most important thing is to write down the wire colors YOU use when you install them (trust me, you will forget which is which if you don't  DON"T ASK!
   Also label the wires. There are not enough different colors for all the wires you will use in your conversion.  Jack

[Hard Headed Ken]

I built a new chassis harness for my 4104 and I ordered numbered wire from a company in Alabama. I ordered the gauge, length and number I wanted on the wire. After I ordered and received the wire I found out that I could have had anything printed on the wire, like left turn, oil pressure, or whatever. Wouldn't that have been nice? The number system works better than color for me. After I drew my diagram I realized it would require about 60 different wires for the harness. I just didn't think 60 color / stripe variations were going to be easy to follow. I think the company was Arnco but I just tried to look them up and no luck. There are other companies that will do this and at the time the cost wasn't much higher than plain colored wire.

Ken

[Sean]

Minor disagreement Sean, 200-6 (in my very old book) says white or natural gray.  ...

Why, Len, you are entirely correct.  Your note sent me back to the code to look it up.  As it turns out, three continuous white stripes also qualify:

"200.6 Means of Identifying Grounded Conductors.

(A) Sizes 6 AWG or Smaller. An insulated grounded conductor of 6 AWG or smaller shall be identified by a continuous white or gray outer finish or by three continuous white stripes on other than green insulation along its entire length. ..."

-Sean
http://OurOdyssey.BlogSpot.com