Hi all, I want to have a programming track connected to my Walthers 130' Turntable (N scale if that matters.) Is the programming track always in programming mode, or can I program the loco on that track, then return it to the layout without frying/resetting everything else? My alternative is to set up the programming track on my working desk. I will be using JMRI, if that matters, and have a Digitrax Evolution for the DCC. Been out of the game for many years, and decided to go all-in on DCC. Have retired laptops for JMRI and a USB cable Thanks in advance.
I think it depends how you wire it. If you isolate that section and then have some kind of selector switch, you might be able to do it. The switch would route power to the track, either from the programming station or the layout. When you are done programming, switch it to the layout power source and move the locomotive off. The switch should be a center-off switch because you do not want multiple power sources going to the same track. That could damage the DCC equipment. That is more of a hypothetical. I have never actually done that with a programming track, so don't exclusively take my word on it.
Thanks all. Looks like the track on the desk wins. Drilling holes through benchwork for wires, gluing almost complete. Productive layout weekend.
Curious to know why you think you need to go that route if you would like one of the leads off the turntable to work as either a program track or not? Wire it like Mike shows and it will work for both along with any other isolated section of track, Sumner
I think he's saying he's done drilling holes for now? My turntable (Fleischmann) routes power to the track it is pointing to, so permanently connecting one of the 'garden tracks' to the programming output of a command station would be dangerous in that situation. I think DCC++EX either can already switch the programming output to track/operations mode, or will be able to do that very soon under software control. Being able to drive a loco onto the programming track, and then automatically enable programming mode for that track from JMRI DecoderPro would be very nice and safe. I'm not sure whether this also requires a software update for JMRI.
Thanks everyone. I don't want to wire a DPDT switch just to have a programming track on the layout. Keeping it simple for now.
A couple of comments: 1. It is very important that any programming track that a loco can run onto from the layout gets set up so that the loco cannot creep back across the isolation and electrically connect the programming track to the whole layout. Locos are designed to move just a bit to indicate each time that a programming command is received. While looking at the computer screen, too many model railroaders have not observed the loco creep to the point where its pickup wheels bridge the programing commands to the whole layout so that every loco on the layout receives the next programming commands. That can mess up every other loco on the layout. 2. So, some sort of dead space between the programing track and the rest of the layout is arranged with a switch or other mechanism. You could use the turntable to run the loco onto the programing lead, and then rotate the turntable so that the loco cannot get back on it. That could serve the function of the "dead section". But you might still need some electrical switching to make sure that the output from the command station when it is in programming track mode goes only to the programming track. How you do that will depend on the command station. Some have only one output that swaps from normal to programing mode, while others have separate outputs for each mode. I am not familiar with the Digitrax Evolution, so somebody else would need to describe how to do it with that particular command station.
I'm going to set up a dedicated programming track on my bench with JMRI and a PR4. The advice from members has convinced me this is the smarter strategy, especially for a complete noob. Sent from my SM-N950U1 using Tapatalk
You could use an NCE Auto SW, and a full bridge rectifier to control a DP relay that switches power to the isolated section between the layout and the programming track. Connect the rectifier to the ASW layout outputs, and the rectifier output to the relay coil such that when unpowered, the relay is open. The relay contacts would connect the ASW layout outputs to the isolated track section, only when powered by the rectifier. Since the ASW's layout outputs are disconnected from the CS when you issue service mode commands, it unpowers the rectifier & relay, which then isolates the isolated section of track automatically. Even if the locomotive creeps over the isolated joint between the programming track and the isolated section, it won't power the rest of the layout and reprogram all the locos. You can connect the programming track to either the programming output of the ASW (which is disconnected when in operating mode), or directly to the CS.
I have done what you asked in your first post a few times in different situations. First off it is a simple thing to do. Secondly it only takes 1 DPDT switch and a feeder wire similar to how you would wire up any other section of track. You would need to isolate both rails via a saw or insulated rail joiners. Then drop a feeder to the center two posts of a DPDT switch (I recommend a center off type) The other posts of the DPDT switch simply go to the track bus and the program track bus. That's it simple as it gets. Also convenient as well since you can just set the loco on the track, get it programmed and then move it onto the layout without touching it again! I usually put my program track as one of the tracks to my engine maintenance shop.
Actually, with more thought into it, it is even simpler than this. You simply power the isolated track from a 2nd Auto SW's "Main" (layout) track output. This 2nd Auto SW is also powered by the same command station/booster that powers the first Auto SW for the main layout track. -- Andy - Arlington TX
