I have several #7s on my layout and have noticed that some of my locomotives slow down as they go through. In one location I have three in a row and the loco completly stalls. I am running the layout with DCC using the NCE PowerCab. I currently do not have any controls hooked up but plan to purchase the Tam Valley servos. Do I need to power the turnouts? If so can somebody tell me how or give me a wiring diagram?
Hi Craig -- Yes, you should wire your Atlas N-scale Code 55 turnouts. I've borrowed the diagram below from the excellent Wiring for DCC web site (http://www.wiringfordcc.com/switches_atlas_roco.htm). I've simplified and re-labeled the diagram somewhat to show how I wire my turnouts. The Wiring for DCC web site suggests more steps -- which are probably a good idea -- but I have kept my turnout wiring very simple. First of all, the connections shown in the diagram between the Point Rails and the Closure Rails and between the Closure Rails and the Stock Rails are built in to the Atlas Code 55 turnouts. Some people recommend duplicating the same connections with your own pieces of wire as a backup to the built in connections. I decided not to do that. Will I regret that later? We'll see! To wire my Atlas Code 55 turnouts, I make three connections shown as the little gray boxes in the diagram. I connect one DCC bus wire to each Stock Rails, and I connect a switched wire to the turnout's Frog Contact. Since I'm using the Tam Valley Quad Boards and servos to operate my turnouts, I also use their Relay Daughter Boards to power the Frogs and switch the Frog polarity. The connection to the Frog is made to the tiny solder lug on the side of the Atlas turnouts. Wiring the turnout has two big benefits. 1. You are not depending on rail joiners to provide power to the turnout. Joiners are not always reliable unless you solder them, and I don't want to do that in case I ever need to replace the turnout. 2. Powering the Frog means that there is no dead spot in the turnout where the loco doesn't receive power. If you don't wire the Frog, it is electrically dead. Check the Wiring for DCC web site for lots more detail. It is a great site. - Jeff
Thank you!!! I am going to use the Tam Valley items as well. Guess it is time to start soldering. Any perticular place you solder the feeder wires to?
I solder my feeders just about where it is shown in the diagram. That's about 4 ties from the ends of the stock rails. I make sure NOT to get any solder on the nearby rail joiners. Edit: Just about anywhere along the stock rails would probably be OK for the feeders, but the location I chose seemed least likely to interfere with any of the electrical conductors that are built into the turnout. - Jeff
jdetray I use many of these turnouts and with a few have noticed some have this problem. Thanks for the tip I will add the wires and see if it helps. Tom
If you are depending on contact between the point and the stock rail to feed power down the line, having a number of turnouts in a row only compounds the situation. The best approach is to cut gaps or install insulating joiners on the frog rails and provide a power feed to both rails at the point end of each turnout. That way, each turnout will have a fresh start.
Hi Doug - What is the benefit of cutting gaps or installing insulating joiners in this situation? All of the turnouts are being connected to the same bus, so why isolate them? - Jeff
If they are connected to the same bus, there is no need to gap them, but be sure that you are not relying on point to stock rail contact or an under the frog jumper to carry all the current should a short occur. Some turnouts power route not by opening the electrical path to the non-selected route, but by connecting both rails together via the closed points. This results in zero volts between the rails, but in the process shorts the two rails of the non-selected route together. No problem unless there is a feed beyond the frog. For both these reasons, as a general rule I gap rails beyond the frog and provide separate feed to the trackage beyond. This works no matter what type turnout you have, and if there is a short (not uncommon) you are not drawing high current through the points or a frog jumper.
