Large Scale Central

Wiring a WYE

I have been planning putting in a WYE on my track powered layout and it is getting there. The track is lined up and ready to be cut to fit now comes the question of how to power this arrangement without popping fuses and setting fires. My idea and I like to keep things simple and cheap is to use on/off switches to isolate each section.
Here is my logic. a WYE has three “legs” the main, the track that is electrically the same as the main and the leg that will reverse the direction of the loco. Say the loco turns off the main and onto one leg without an issue. I stop the loco, hit the switch on my TE to reverse direction but before I do that I will throw 2 switches one for each rail to kill power to the section I just went over and then turn on 2 more switches that will power the section “3rd leg” that I want to get onto to reverse the loco. Since I jsut reversed the direction on my TE and transformer the polarity will change on the track. Power will be taken from the main to power each section or leg accordingly. The Aristocraft WYE turnout will be powered by which ever leg is on. At the end of the line after the WYE switch will be 2 track yard that will not be connected to the rest of the RR.
The only trouble I forsee is if I forget to throw a turnout and the loco gets onto the unpowered track but if both rails are dead this should only stop it and not cause a short. of course if all 4 switches were turned on the fuses on my TE would FRY.
In the past I have used electric light switches and lamp cord to power or unpower sidings so I can park trains. The switches are cheap and highly visible. I will just need to build a structure to house 4 of them.
Obviously this arrangement would only allow one train to be run at a time.
What do you guys think of my plan ? Feel free to comment to tell me it won’t work but please state why.
Thanks
Todd

It’s a little confusing to read, but it sounds like you want to use a bunch of single pole single throw switches to control power.

All you really need to do is to be able to reverse the power “in” the wye. The easiest way is to put in insulators in one segment of the “triangle” that is formed by the wye… the part that would connect the top legs of “Y” … then you put a double pole, double throw switch that is powered from the track, so you can reverse that section independently.

If your trains all fit within that section, things are simple. You can even hook up some lights between the rails to show that the polarity is right before you try to cross it with a loco.

Do you have a rough sketch with the configuration and lengths of the “legs”? Remember that lit cars and even metal wheels can cause complications if you have a train longer than the “reversing segment”…

Regards, Greg

Like Greg said, it’s not quite as complicated as you make it. If one tail is a dead end, as mine is, it’s very simple. You need only one DPDT switch. Use the DPDT to set the polarity the same as the track you are on. Proceed into the tail, then stop. Flip the DPDT to align polarity with the exit track and throttle up. The train will reverse because the polarity has reversed with no action required on the TE. In this diagram the frog wiring logic is flawed, but the track connections are correct…

(http://lsc.cvsry.com/Wye_Polarity.jpg)

EDIT to clarify - The dead-end tail is to the right on this drawing. Tack power is picked up from the rails ahead of the turn out.

And you have some flexibility in where you put the insulated joints.

If you have a situation where one of the 3 legs of the wye is a dead end “tail”, then you can either insulate the 2 “legs” and leave the “main line” unbroken, or you can insulate the one side of the triangle that is on the main, and reverse the others…

That’s why I suggested including a rough sketch.

Don’t let it intimidate you.

Regards, Greg

Guess what Greg it does intimidate me. I don’t know what a DPDT switch is? a sketch would help but I don’t know how to upload it. I’m not great with this electronic and computer stuff.
I want to leave the main untouched but I believe that the other 2 legs need to be insulated. If polarity along one leg and the main is switched by a single switch then how will the one leg left be switched or turned off to avoid a short? I’m using a #6 wye switch from aristocraft and it has a powered frog and a switch underneath. I inquired about protecting this circuit from the elements and I believe you Greg posted pictures of a destroyed one that you had. Will there be issues with this electrical arrangement under the switch?
The longest leg is the main at about 9 feet the dead end will be a maybe 12 feet.
I do want to keep this as simple as possible. I will hold off building the “switch” tower building until I get this figured out.
Thanks
Todd

On my new layout I used an Atlas controller on my Wye, it was simple to wire up and it actually works. I am track powered w/ single power pack with a Basic Train Engineer R/C controller so my Wye power connection was simpler than the diagram on the back of the package indicated, the guys at Whistle Stop helped explain it to me when I bought it.

(http://img2.toysperiod.com/img/cache/5a/200x150/r2z254n2o5m4p5x3t254p2l274u2t2.jpg)

Double insulated rails each end of the wye section then connect the +/- leads from the power pack to Cab A inputs (red switch left top), feed a jumper wire from the adjacent section to the directional inputs (top right) and then connect the +/- connectors from the directional inputs to the wye rails, the directional switch (grey switch right center) controls the polarity of the wye.

(http://1stclass.mylargescale.com/vsmith/Layout-New%20Direction%20Reduex%20Power%20Diagram.jpg)

Heres how it looks on my wiring diagram, as long as the red switch Cab A is kept in one position all you have to do change the wye directional switch to control the polarity of the train once its on the wye. Luckily if its wired right the switch should (like mine) end up where when the switch is on the left its polarity matches the left hand trand and viseversa on the right side, so all I do if the engine is coming from the left is to set the wye switch to the left, run the engine onto the wye, stop it, flip the switch to the right, hit reverse direction on the BTE controller and power up and it rolls off to the the right hand side which is also now the correct polarity thanks to the BTE system. Yeah sounds complicated, but I wired it up in less than an 1/2 hour and took less than than learning to use it in operation.

(http://upload.wikimedia.org/wikipedia/commons/8/89/Bomba_atomowa.gif)

(http://upload.wikimedia.org/wikipedia/commons/8/89/Bomba_atomowa.gif)

What he said. Referring to the first pic that was nuc’ed. Great gif, Rooster. Mind if’n I steal it?

Todd, the picture that Jon posted is the underside of a DPDT switch. those 6 circles exactly parallel what you would see on the back of the switch, 6 connections in that configuration.

I’d follow exactly what he said, although I’ve begged for a rough drawing (or picture) of what you are doing.

This would be a manual system with one switch that would do what you asked, although you will need to change the mainline polarity too with the direction switch on your controller.

Regards, Greg

By no means am I challenging the diagrams …I just thought the GIF was kinda funny …Actually Jon started that awhile back and I was looking for that pic but could not find it.

Greg Elmassian said:
This would be a manual system with one switch that would do what you asked, although you will need to change the mainline polarity too with the direction switch on your controller.

Regards, Greg


Not exactly. If you switch only the dead-end tail. Set the polarity of the tail to be the same as the main before entering. Enter the tail and stop. Filip the switch setting the tail polarity to that of the exit track. Throttle up and you will move toward the exit. When you get to the end of the next tail, you simply stop and change direction on the controller to exit the second tail in the opposite direction. Technically, that second stop did change the polarity of the main, but you don’t do it until after entering the second tail.

I do have a color coded diagram of a complete wye somewhere. I’ll try and post it

Here it is…

(http://lsc.cvsry.com/Wye_Diagram-800.JPG)

ha! you are right… if you are entering the mainline after you have left it, for the express purpose of reversing direction, you are right.

But, if you are already on the wye, and you want to go a particular way on the main, you MAY have to reverse the polarity of the main to match the direction you want to proceed…

That’s all I was trying to say, but wanted not to type this much!

Regards, Greg

Well the WYE is in but not wired yet. You guys have been a help with suggestions and diagrams but I’m still having a mental freeze on how to wire this pup. In my HO days like 20 years ago I remembered that I had a double main that passed through a yard and I used the Atlas controller like Victor Smith is using to reverse the polarity and it worked well.
I can’t get a diagram of my plan posted since I’m working off a laptop here. But a WYE is a wye. Mine is built on a bit of a curve. If we look at Jon Radders diagram my mainline is at the bottom. I have LGB #6 turnouts coming off the main and they form into the Aristocraft Wye switch at the top of Jons diagram and that is where the track dead ends. a train will approach from the west of jons diagram and enter the Wye. I figured I would leave this as a common leg and do the switching of polarity when the train enters the dead end. I’m confused again… LOL
In my mind both legs would need to be insulated from the main. One is ON the other is OFF so polarity doesn’t conflict. The tail or dead end would need to be oriented depending on how the train arrived and then how it will leave. My plan… Drive on to the dead end tail. Stop, reverse direction on my TE and power off the track I just drove over then power up the other leg to exit the wye… ? Sounds simple enough… NOT
Where can I get a DPDT switch?
Thanks guys for your patience and trying to align MY polarity LOL

Where can I get a DPDT switch? Todd just about any electronics supply store or on-line. Typical DTDP Switch

(http://freightsheds.largescalecentral.com/users/kettle_valley/forumfiles/31BsLz31lNL__SL210.jpg)

And that one is a “center off”, so there is a middle position that leaves power un-connected… not a bad idea… Available from Radio Shack http://www.radioshack.com/product/index.jsp?productId=2062518

(http://rsk.imageg.net/graphics/product_images/pRS1C-2160427w345.jpg)

In reference to Jon’s diagram, there’s many ways to do it. I’d not put the insulators on the main line, put 2 insulators on the other “leg” of the wye, so each side is a mirror image of itself. Now connect the switch as shown in the drawing… the only difference is you took the 2 insulators from the main line and put them on the other leg. Jon’s circuit does not work if the mainline is a loop… it works if you are point to point on the mainline. Regards, Greg

Greg Elmassian said:
Jon's circuit does not work if the mainline is a loop... it works if you are point to point on the mainline. Regards, Greg
If the main-line is the bottom of the diagram, you are correct. I am point-to-point and two ends of my wye (right and top) are a dead end.

So lets say the arc on the left is the main, and it is a circle, the right hand is the dead-end tail Todd says he has. Wouldn’t this still work? The insulators and the DPDT switch are connected to the main-line side (the two diverging routes) of his wye switch. The insulators would isolate the shorting section and the switch would set it’s polarity to either be opposite to, or match the main. In this scenario you would need to use the controller to reverse direction if you enter at the top of the diagram, but not if you enter at the bottom, in that case the DPDT does it.

Insulators could still go where the wye leaves the main if that is more convenient.

Where is that dead horse image when you need it ?

Jon Radder said:
Where is that dead horse image when you need it ?
:)

Jon, you are right again. I should have said if the mainline is the track at the bottom (and I assumed your “tail” was the dead end), then I’m accurate. If the mainline is as you say in your post, then you are right. Of course with all this confusion, we may have Todd jumping off a cliff soon, ha ha! Greg

(http://www.elmassian.com/images/stories/misc/beating_dead_horse.gif)

(http://www.elmassian.com/images/stories/misc/beating_dead_horse.gif)

That’s the one :smiley: Todd - Unless you have specific questions, I think we’re done confusing you.