Why Red and Black?

As long as I have unique colors and know what they mean, I don't spend much time trying to correlate them to 120VAC wiring.

 

I am with GRJ, have three loops and two feeds for accessories, all with different colors. However, I do use white for the neutral ( I was brainwashed on that).

For common I use green or white.  I use one common return for the entire layout. If an accessory has red and black I wrap the black wire with green tracer tape to avoid confusion. As John says the color is arbitrary as long as the user knows the code.

 

Dale H

hmmmm....

 

I have decided that a different color scheme was selected for safety reasons to indicate that it is low voltage\low amperage AC.

 

I no longer ponder it and use whichever colors I like, with black as common\neutral , as long as it is different from U.S. AC standards.

Wanderer, it sounds like you're like me, coming from a background of house wiring - 120 and 240 V AC.  As a building contractor for many years, the convention of black and red for hot, and white for neutral, was so drilled into my head that it was unquestioned - which is as it should be, in that context.  House wiring would never pass building inspection, and would be downright dangerous, if every electrician made up his own idea which color wire to use for hot.

 

But I learned pretty quickly that is not the case with low voltage hobby wiring.  As you note, a lot of 2-conductor low voltage wire comes red and black.  So using white as neutral was not an option, brainwashing or not.  So I just settled on my own standard, and stuck to it.  Black is neutral on my layout. 

 

And I found that most of the 4-conductor I bought was red, black, yellow, and green. Since a lot of signals and turnouts on a layout show red and green lights, it makes sense to use the red and green wires for them, keeping black as common and then you are using the yellow as your line hot.

 

Sometimes you end up with good, useable pieces of wire that are the "wrong" color.  In house wiring this is not an option, but in hobby wiring it can be more economical to use these instead of cutting into a new roll.  Just try to be consistent, and as Dale notes, you can mark the ends of odd-colored wire with colored tape to conform to your own "code".

 

david

Wanderer,

   I agree with Gun son this one, if my 14 Gauge wire would have had a different color scheme it would not have made one bit of difference to me, I do like the mid rail Red and the outside rail Back or White however, easy to identify at a glance while building the layouts.

PCRR/Dave

 

     

If you want some real confusion in the telephone switching world red is negative and black is positive. Also in some instamtces blue can be negative also!

Early AC wires with transformers from Lionel were the same color. Could be Brown, Black, or Green.   You were told what terminal post had to go to center rail for the whistle control.

 

Modern transformers probably adopted the colors so that wiring for Bell/Whistle worked since transformers lost the terminal identification.   Lionel still sold same color wires, but one had a trace on it.  What do you think was easier to see, red versus black, or a white trace on a black wire.  G 

I try to be consistent.....

 

Black is ground

Red is power to track.....tag each independent loop.

 

Green is the 16 volt line (switches and some accessories)

Yellow is the 14 volt line (accessories)

Blue is the 12 volt line (lights and some accessories)

 

 

Peter

So many ways to skin the cat. 

 

Thanks for for the replies...it's interesting to know the history and the different approaches everyone has taken. 

I used red and black on one loop and orange and black on the other.  Red and Orange are the hot wires and black is the ground.  To be safe I wired one loop at a time so I didn't cross connect the black wires.