I'm new to Model Railroading and am Very Ignorant. I rigged up a reversing setup on my layout (I used three turnouts arranged in a triangle), but when I connected the tracks, they shorted out. Duh! Of course they did, but isn't there a way to rig a reversing setup? (I have a DCC locomotive.) (Sort of like when you pull your pickup into somebody's driveway and back out so you're looking back the way you came.) I've seen pictures of this kind of arrangement, but they use two turnouts and a wye. I thought that was probably so the tracks fit together better. The way I had it, I was going to have to add in a little one and one-eighth piece of track. I can get a wye if I need to, but it's the short I don't know what to do about. Can any of y'all tell me what to do?
It just this minute occurred to me that I might could insulate the track somewhere in that arrangement. Would that work? (Somehow, I doubt if it would be that easy.) (Just in case that wouldn't work, my question still stands.)
Electrical blocks are required for wiring a wye or reverse loop without creating a short.
This page has info on doing it for DCC and regular DC layouts: http://www.building-your-model-railroad.com/model-railroad-wiring.html (http://www.building-your-model-railroad.com/model-railroad-wiring.html)
Len
Nice find, Len.
It covers many of the important chapters found in the Atlas #12 wiring book.
Thanks.
Joe
Edit: changed "parts" to "chapters".
Joe,
One of these days I may get around to doing a post with the 30 or so, not counting manufacturers and Yahoo Groups, handy MRR links I keep in my bookmarks list.
Len
All right then, I'll get on that page. Thanks.
does one of the tracks in your arrangement (which is itself known as a wye) dead end? if so, it is possible to wire an atlas snap relay in parallel with the switch on the stub track, so that this stub changes polarity when you throw the switch. instructions on how to do this come packaged with the snap relay. in the meantime, to eliminate the short so you can run trains normally, you will have to use insulating rail joiners to electrically isolate this switch and the stub ( called a tail track) from the rest of your layout. once you get the snap relay, you can wire the tail according to directions.
the atlas snap relay is probably less than half the price of the autoreverse unit you wopuld otherwise need to switch polarity, and you'd still need to isolate this section from the rest of the layout.
Okay, I think I understand, except for one thing. They have a sketch (on that wiring web page that Len mentioned) that shows reversing both the isolated section and the main line. I understand why I have to reverse the isolated part, according to which fork of the wye needs to match the main line, but why can't the main line stay like it is? It seems to me that I would just have to make sure I don't run a train into the mismatched fork. (I hope I'm not being too obtuse). And yes, I like the "snap relay" idea rather than the automatic "module" because I would be better able to tell what's happening. Thank y'all for your help and your patience.
you are right. you don't need an autoreverser for your mainline. just reversing the tail of the wye will do the trick. a good rule of thumb is that anywhere a train can turn around and run the same section of track in the opposite direction while still moving forward, you need a reversing section. if the wye is the only place you can do this, it is the only section that needs special wiring. this applies whether you run dc or dcc.
Thanks, jward; that's just exactly the answer I was looking for. It's a relief to get that settled in my mind. Now I can move on to a different track. I'm sure it won't be long before I stumble on to something else I don't understand.
You are not alone...
I've been at this for close to 50 years and still run up against head-scratching situations...
You gotta just keep plodding along...
Gus.
Cool! Looks like I'm among the Right People.
Looks like everything I ever learned about electricity just flew out the window. I just received the wye I ordered. It's supposed to be "electrically gapped", but for the life of me, I can't see a gap anywhere when I check for continuity with my ohmmeter. I expected to see one leg open while the other leg was closed (and vice versa when I flip the switch). What I am actually seeing is all rails (respectively) connected as if there were no gap. I can see the relay contact swing from one contact to another, but shouldn't I see something change with my meter? Is there a circuit diagram somewhere? What I'm seeing with my meter indicates that I would have a short circuit relative to the main line just as if I were using an ordinary (ungapped) turnout. Am I wrong when I expect to see one leg open?
And here's something else: I can't seem to figure out how to connect this wye to the other track sections. I can connect to one leg, but the other leg looks like it needs some kind of special something. The ordinary turnouts connect just fine, but one leg is longer than the other to make room. The legs on this one don't have any length. It's labelled as a #5 turnout. Am I supposed to cut away part of the roadbed of the piece I'm trying to connect, or is there a special piece I can order that will fit?
Any light y'all could shed would be greatly appreciated. I keep thinking all this would be fun if I can get to where I understand it. I guess that kind of understanding comes slowly but gradually. (And that's okay.)
Here's a question about connecting power to that wye: The instructions say to connect the transfer switch to the accessory terminals of my controller. My E-Z Command controller doesn't have accessory terminals. (And that's another question: why doesn't it?) Also, how do I connect this controller to my isolated section of track? Is there a splitter I can order, such that I could piggyback at the "To Track" jack? Is that even how you're supposed to do it? As for all the ordinary accessories, I could use a whole other transformer, but if I'm going to control the train, it looks like I have to connect to the E-Z Command controller. I've seen in the catalog where I can get sections of track that have power connectors on them. I wouldn't mind using those, but then I would need wires with those little connectors on both ends. Can I order something like that? (I hope I'm not really as dumb as I must sound.)
Quote from: rufuswhite@gmx.com on April 02, 2015, 12:14:16 PM
Here's a question about connecting power to that wye: The instructions say to connect the transfer switch to the accessory terminals of my controller. My E-Z Command controller doesn't have accessory terminals. (And that's another question: why doesn't it?) Also, how do I connect this controller to my isolated section of track? Is there a splitter I can order, such that I could piggyback at the "To Track" jack? Is that even how you're supposed to do it? As for all the ordinary accessories, I could use a whole other transformer, but if I'm going to control the train, it looks like I have to connect to the E-Z Command controller. I've seen in the catalog where I can get sections of track that have power connectors on them. I wouldn't mind using those, but then I would need wires with those little connectors on both ends. Can I order something like that? (I hope I'm not really as dumb as I must sound.)
It is better to use a spare dc pack or wallwart from a cell phone or old toy. Tapping in to the DCC rails will draw current from your system when you switch. This also causes a lower voltage to operate the switch thus making it operate slower or hesitant.
RW,
There are no accessories terminals on the E-Z Command unit.
You will need to find another source of 12 to 16VAC to run your turnouts.
If you have a Local Hobby Shop (LHS) nearby, they probably have boxes of used
starter-set DC power packs (that have accessories terminals) for a very reasonable price.
You need to trim the roadbed of any track pieces that you want to attach to the main and
divergent routes of the #5 (& other numbered?) HO E-Z Track turnouts.
Since I don't see insulated rail joiners (connectors) in the on-line catalog, I assume that
Bachmann doesn't make them, and I'm allowed to say that Atlas makes them (#0055).
They take the place of the gaps.
If you are running DCC, go get a DCC auto-reverser. Your turn-arounds will be much easier.
Hope this helps.
Sincerely,
Joe Satnik
Okay, so I'll trim my roadbed for the #5 wye, and I'll use a separate transformer for accessories. Thanks, y'all.
I am assuming you already have a snap relay? if so, do the following....
first off, both rails must be insulated on each of the 2 legs of your wye that connect to your main track. you can do this by replacing the metal rail joiners with plastic ones. those 4 insulated joints should be the only insulated ones in your wye formation. checque with your meter, the wye switch and the tail track should no receive no power from the mainline.
next step, assuming you have already wired the wye switch motor to the power pack, disconnect the wire and cut about halfway down the cable. separate each wire from the others, and connect them to a terminal block. you should have wires in 3 positions on the block, with the center wires from each half of the switch cable connected to the center position on the block. next connect the outer wires to the outer positions on the block. at this point, you should have 2 wires connected to each position on the block.
next, the snap relay should have come with short 3 conductor cable, with red/green & black wires. connect one end of this cable to the 3 contacts on the very end of the snap relay, with the black wire on the center terminal and the other two on the outer terminals. do the same with the other end of the cable, at the terminal block, black wire to center terminal. at this point, test the switch and snap relay, both should throw when you activate the switch control box.
along each side of the snap relay you will notice terminals marked a, b & c. connect the two "c" terminals to the rails of the tail track, one terminal to each rail. connect the "a" terminals on the relay to the rails of your mainline track, one to each rail. finally, cut two short wires and use them to jumper the "a" terminal on one side of the relay to the "b" terminal on the opposite side. connect the other "a" terminal to the remaining "b" terminal, the end result should look like an X.
now, test the wye by throwing the switch and snap relay again. both should move when you activate the control box. test with your meter to ensure that the rails on either side of the gap, on the track that the wye switch is lined for, are the same polarity. you should get a reading of 0 volts here. if not, reverse the red and green wires at the end of the snap relay, and throw the switch again. this should give you the correct polarity to run a locomotive into the tail track and stop. throw the switch, and the polarity should be good to run the locomotive out the other leg of the wye to the mainline.
sorry, I have no wiring diagram to give you, but I hope these step by step instructions are enough to guide you through the wiring. it's really a lot easier than it sounds.
Yes, that does sound complicated, but I can visualize the operation. I don't have a snap relay yet, so that will be my next step. I can see that a snap relay would be better than the automatic module because of the cost. Since I have to throw the switch anyway, the snap relay/switch motor combination would be near enough automatic.
Meanwhile, I have discovered more mysteries concerning track power. After I isolated my wye, I ran the train over it expecting it to stop. On one leg, it stopped all right, but on the other leg, it stopped at a whole other turnout before it got to the isolated section. I'll have to do some investigating, but it seems to have something to do with the frog. I figure to take some continuity readings and compare with another turnout. Please let me know if you hear of a way I can get some schematic diagrams. A picture really is worth a thousand words.