Greetings to All, I have a question about reverse loops in DCC. I bought a couple of PSX-AR’s and plan to use them on a dogbone track plan. I have two LGB 22.5 turnouts that I will use. These have electric switch machines that I may or may not fire up as needed. I understand how to wire it up for polarity-really pretty simple-like my HO or N scale. In these scales, I have to pay attention and throw the switch after the train runs through so when it comes back around it doesn’t hit a closed switch. For my large scale, I want it to run continuously. Will the engine throw the switch without shorting on the way back through? I thought I read that they could do this in analog but could not find it as I went through a variety of online info. If it doesn’t. it seems the PSX-AR will control a switch machine (Tortoise) that can. Will the PSX-AR operate the LGB switch motors? I guess my bigger question is, how do I get simple, continuous running (where I can walk away from it) on a simple dogbone, reverse loop layout? KISS is important to me. I was reading a recent thread by Devon Sinsley about turnouts and also some other topics here and sometimes the technical side turns my brain into a pretzel. The knowledge out there is pretty awesome! Thanks, Phil Nymark
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the autoreverser will not throw the switch unless it has the capability and you connect it up.
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just insulate the loop past the switch.
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Make a floppy switch, so the train enters in whatever direction it was left in, and when it leaves the loop it pushes the switch over.
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you can make the floppy mechanism leave the switch in the last direction it was moved, or you can make it so it always returns to the same position, it’s a simple matter of where you drill the hole, look at that picture in Devon’s thread.
To summarize, insulate the rails past the switch, connect the autoreverser output to that insulated loop. Make a floppy switch and you are done.
Greg
Thank you Greg, I plan on experimenting with this before I do a permanent track plan.Hope I don’t blow up my SB5 again, the PH-10 might be a while coming. I bought a role of solid AWG 12 wire for my bus and have been thinking of running it inside of drip line for better outside protection. Also, I want to slightly elevate the track on some type of brick, border it with flexible garden borders and fill it with 3/8 crushed gravel from a local supply. Little by little I’m getting an idea of how this is going to work. Lots of inspiration in posts and photos and lots of fun-Phil
Phil, if you are having fun, then you are doing it right.
Well I pulled out my new LGB turnouts and found the literature that explains control-this is where I read about how the locos can flip the switch. The electric motor control will act as a spring and hold the position of the switch after the engine runs through. Haven’t done it yet but think it will work. Little by little and hope I don’t blow a decoder or something.
Phil Nymark said:
Well I pulled out my new LGB turnouts and found the literature that explains control-this is where I read about how the locos can flip the switch. The electric motor control will act as a spring and hold the position of the switch after the engine runs through. Haven’t done it yet but think it will work. Little by little and hope I don’t blow a decoder or something.
David Maynard said:
Phil, if you are having fun, then you are doing it right.
Thanks David!
Phil, decoders can really only be blown by improper wiring (typically not having the track pickups isolated from the motor wires), or excessive current draw (motor dead short/burned up) or excessive current draw on function outputs.
Once you have a good installation, they are pretty much impossible to blow up.
More common problems is a short on the main line, and running 5 or 10 amps through a short, like shorting from the rear truck to the front truck and the short goes through the internal loco wiring (not the decoder).
Also, the PSX-AR is a circuit breaker as well as an autoreverser, even more protection… use the jumper settings at first to set the max current. There are LEDs on it that tell you what is going on.
I have an entire page on it: http://elmassian.com/index.php?option=com_content&view=article&id=166:dcc-specialties&catid=55:dcc-general&Itemid=199
Greg
More info that I would not have realized. Thanks Greg. I planned on buying the 270-1805 but would not have known to mill it down. For now, I’m running a single Bachmann 3 truck Shay on an SB5 so I don’t think I need the heat sinks yet. I did buy a 24 volt 13 amp Meanwell in anticipation of the NCE PH-10. In the “programming notes” section you mention CV 49 sets the current trip point. This can be done with my NCE system? Pretty cool stuff-Phil
Yes, no reason for the heat sinks unless you start running 10 amps continuously in the reverse loop. I really did not need the heat sinks, but I just added it to be bulletproof.
Yes, CV49 will set the trip point, and yes you can do it with the NCE system. What I said is starting out, just use the jumper, since you are just getting used to what set points you want.
After you get everything working to your satisfaction, I would indeed recommend setting the trip point with a CV.
Yes, it is quite a capable unit, and you will find it is the preferred unit in all clubs and organizations due to it’s flexibility, robustness, and quality.
Greg
I’m going to review the literature I bookmarked for the PSX-AR and get a better idea of how the more technical stuff works. After owning my NCE Powercab for many years I still haven’t accessed all it can do. Large scale is pushing me to understand some of the more technical stuff. Much of the skills required for model RR I’m okay at-benchwork, track, scenery and painting backdrops, building models. But when it comes to the electric/tech stuff I’m not so good but enjoy the challenge. Again, thanks for all the knowledge-Phil
Phil Nymark said:
Well I pulled out my new LGB turnouts and found the literature that explains control-this is where I read about how the locos can flip the switch. The electric motor control will act as a spring and hold the position of the switch after the engine runs through. Haven’t done it yet but think it will work. Little by little and hope I don’t blow a decoder or something.
Using this “portion” of the LGB reverse loop technique, there is really no reason not to follow through with it. The LGB system can not only flip the turnout, it can take care of any rail polarity problems, just as it does for simple dc. You don’t need any dcc reversers if you wire it up correctly and would be $$$ ahead.
Hey Todd, Are you referring to the LGB reverse track in conjunction with the LGB turnouts? I did buy the PSX-AR’s but have a set of the LGB reverse track. I was told these track pieces did not work so well with DCC (thus the PSX-AR purchase). I would like to know more about the technique you mention. Thanks-Phil
The LGB reverse loops set keeps simple dc from shorting out by changing the polarity of the mainline while the train is in the loop so there is no short circuit.
Since the function is to keep the system from shorting out, there is no reason that I can see why this won’t work with dcc also.
Actually, it should work better for dcc. If there are other dcc trains out on the line they should keep their heading when the polarity changes whereas if you had another dc train out there, it would start running in reverse.
i belive the little magic lgb boxes cost more than the psx-ar, and you have a lot more wiring, and no built in short circuit detection… also i think lgb boxes have relays… psx-ar has no relays… I’ll stick to the psx-ar
The “magic” lgb boxes are simply the turnout throw mechanisms/dpdts and reed switches that he said he will use (and has) anyways. So we’re only talking about one more throw mechanism with the dpdt switch on it…, if he doesn’t already have it.
As for wiring, most men can read a road map. As for protection, a fuse is probably as cheap as a…
I did not say he could not read the wiring diagram, I said the solution you proposed has a lot more wiring.
Most men can read English.
Greg
I am hoping to be able to run my engine continuously on reverse loops without having to throw switches or pay attention to what the engine is doing. I have the PSX-AR’s and understand the simple wiring that is needed-pretty much just like my MRC reverser I use in N and HO (I replaced my more complicated AR-1’s). In these scales it has been my goal to find a way to automate the switch so it changes after the train passes through so as to prevent the train from hitting a closed switch on its way back.I think I would need switch decoders but haven’t looked into it. This hasn’t been much of a priority but will be more important to me in my garden RR. The LGB info that comes with the turnouts seems to indicate that the weight of the engine will bump the switch open upon return so my plan was to mock it up and see. I have been trying to do my homework by studying a variety of websites (thanks Greg E.) dealing with these issues so I can keep up with the help I receive. And Todd, thank you for the schematic-I will look into this alternative to add to my understanding. As an aside, I was just joking with my wife that I don’t even have the skills to download such a schematic. Lots of work to do here in Santa Rosa!
Phil, there have been a few threads here about spring switches and flop switches. So if the locomotive AND cars cant push over the points on the LGB switch, then you might dig up the threads I mentioned, and try one of the ideas/suggestions in the threads.
What a few people here on the thread don’t realize is the PSX series has various options, including one that will drive a switch when it reverses.
I see Phil knows this about the PSX series.
Greg