Beginner Question: Snap Switch Wire Colors?

I’m just plotting the wiring on my first layout…haven’t installed anything yet…so don’t know which of the three wires on the Atlas Snap Switches…red, green, or black…is the common wire…i.e. the one I can join up off common one from the power supply so that I don’t have to run all three from every switch machine back to the power supply?

Would like to know so I can get the right color coding on my wiring diagram.

Thanks

It’s not the wire that makes that call, it’s the terminal you connect it to. On Atlas snap-switches, the center terminal of the switch machine is the common terminal. That’s also the case with the controller buttons, I think, but I don’t use them because they’re kind of unreliable, and they don’t work well on a “schematic” track plan control panel like I use.

The “standard” use of the 3-wire cable would be black to the center and red/green to the outsides. Some people always use green for the straight path and red for curved, while others use green for the “main line” path, whether that be straight or curved. It really doesn’t matter.

You will quickly find that the wire they provide with the snap-switches is too short for any practical use. I went to Home Depot and bought 4-conductor phone wire, less than $10 for a hundred-foot roll.

Doesn’t matter what color wire you use, just be consistent with all of them.

How about someone telling us how to wire these up using a toggle switch and a momentary push button. I have seen this somewhere but can’t remember where. I have one of these at the top of a helix out of sight and don’t want to use the controller.

Thanks Clay Smith

Clay

It’s really the same as using the Atlas controller. The center terminal on the switch machine goes to one side of your power supply. The outer 2 terminals go to a terminal on each of the push buttons or the 2 outer terminals on the SPDT (make sure it’s spring-loaded momentary!) toggle. The other terminals on the push buttons, or the center terminal on the toggle go to the other terminal on the power supply.

I really urge getting a copy of Kalmbach’s Basic Electricity and Control Systems download (http://kalmbachcatalog.stores.yahoo.net/mrpdf009.html) or one of the wiring books found on this page - http://kalmbachcatalog.stores.yahoo.net/model-railroading-books-wiring-electronics.html .

Getting a basic understanding of why and how to wire various devices is an important model railroading skill, just like soldering, applying decals, painting, cleaning and lubricating, etc. You don’t want to be locked into blindly following color-coded wiring plugs and instructions. There will be too many occasions when a little understanding will resolve unanticipated problems. Learning new skills has been one of the greatest benefits (besides the sheer fun) of model railroading for me. In my case, it was the wiring I learned helping my father with his Lionel and HO layouts as a kid that drew me into electrical engineering as an adult.

Finally, a Capacitive Discharge (CD) unit will help with many of the typical ills of using twin-coil switc

Fred,

Thank you for your help.

Regards Clay Smith