Is there a generally accepted color code for model railroad wiring? I know there is a standard for DCC decoder wiring colors, but I am thinking of "under the layout" wiring: main bus and track feeders frog power routing block detection and signaling lighting and accessory power etc. I'm just curious if there might be recommended practices or standards for this sort of thing. I did not find anything about this on the NMRA web site. I realize that the most important thing is to establish standards and follow them for your own layout. - Jeff
Here is my standard I don't know about any standard, but I've come up with my own. Booster A - Orange Booster B - Brown Booster Ground - Green These are straight from the booster, before it reaches any power management, Rail A - Red Rail B - Black This coming out of the Power Manager and feeding to track. Rail B Detection Section 1 - White Rail B Detection Section 2 - Blue Rail B Detection Section 3 - Yellow Rail B Detection Section 4 - Green This applies to each 4 section detection Zone, based on using a Digitrax BDL168. Rail A Reversing Section - Clear Copper Rail B Reversing Section - Clear Silver This is 14 AWG speaker wire. Color coded detection zones. I printed labels to help me keep the proper order when I brought everything to a terminal block. Accessories Neg. - Purple Accessories Pos. - Pink I chose so many colors because everything above is 14 AWG. It really helps me distinguish which is which. For track feeders I always use: Rail A - Red Rail B - Black For Frogs I feed with Rail A - Red Rail B - Black Frog - Green For Turnout motors, I use a White 4 conductor wire. I put green and white to pins 1 and 8 of the Tortoise, I use the red and black for frog power or feedback. I haven't gotten to signals yet, but I figure they will be pretty obvious If I use flat ribbon cable.
Hi Greg - If the NMRA wants to establish an "official" color code, all they have to do is refer everyone to your post. That's excellent! I like the Molex connectors, too, and I just happen to have a bunch of them. Thanks! - Jeff
I suspect the NMRA won't do a recommended code for layouts, exactly because of your last comment - unlike a manufacturer who buys supplies to order, most hobbyists will use what they have and/or what is cheap and/or what is readily available in local stores. So heavy bus cable will tend to be red/black (if that is normal in USA), though in Europe/UK red/black will probably give way to brown/blue as that is now standard for power wiring. I'm not averse to bespoke colouring as well. My track feeds are red/black, but the switched feeds to the live frogs use red wire with black dashes applied with marker pen .
Similarly, I use red/black for track wiring but also for the Tortoise motor power, which is separate from the track (though I may revisit that with blue/brown). For the auxiliary contacts I use red/black for track power into the Tortoise and a deep yellow for the output to the frog and the indication side follows DCC lighting standard with blue + input and white for normal and pale yellow for reverse indication. As long as you create your own standard and follow it, at least you can install and find any faults relatively easily!
Don't forget to write down all your wiring. With color coded wires this is more easy, but you need a written memory. I know it ! Wolfgang
