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Discussion Starter · #1 ·
Does anybody have a link to wiring around a N scale PECO double cross over?

I am going to make it change/flip with an ESU Ecos comand Control and of course a decoder to send the power to the motors so I don't have to worry about the DPDT switch right?

I thought I saw somebody said someplace that you put small sections of track on the 4 ends and then insulate it from the rest of the track with it's own block>?

Also being a NOOB and just starting I have to ask. I am going to throw the switch or rails per say with tunout/solinoid style motors below...My question on this is that could you use the feed from ONE decoder to snap all the motors or do you need a separate decoder for each motor?

Finally the frogs...Wouldn't it be easie rto just use frog juicers attached to the frog wires then they'd always switch right?

Sorry I am just a noob but the layout I am making has quite a few of these so I need to nail it down...
Thanks!
Ron

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Basically, any time you use a double crossover, you create a reversing loop, which is a situation where a train can leave a turnout on one leg and com back on the opposite leg without reversing direction. This causes a polarity conflict in the rail wiring, because what was once the right rail wants to become the left, electrically. The solution to this is to wire an isolated section of track with s reversing loop controller, which will switch the polarity of the rail almost instantly, resolving the polarity conflict. Ideally, each section should be longer than your longest train, so things like lighted cars or uninsulated metal wheels don't bridge the gap and cause a short. It MUST be longer than your longest loco (including tender, if applicable). You will need a separate controller for each isolated track segment.

Frog juicers may help with powered frogs and keeping the polarity of the frogs straight, but they won't fix the reversing loop problem with the double crossover.

Under table turnout machines. I use Tam Valley servos (since you know the frog juicer, you probably know their products). This has a special crossover controller which will simultaneously move both turnouts in a crossover. This is a good idea, since you don't want to move ONE turnout to the crossover route and leave the other lined for the main. With this arrangement, one decoder covers both turnouts (or sets of points). Otherwise, I'm pretty sure you need one decoder for each switch motor (being a TVD guy, I've never done it myself -- I actually don't even use DCC to throw my points; I want the train crews to deal with it).
 

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No special wiring for a Walthers/Shinohara HO Code 83 double-crossover. Are you sure the PECO variety is different?

Your parallel mains leading to the four entrances to the DC are wired in parallel as well. Left rail and right rail both have the same polarity/phase. So, the stub ends of the DC get the same treatment. Thereafter, the DC should be internally jumpered to get power to the bits of rail that are isolated near the frogs. All you need to do is to ensure the two sets of opposite points match for the direction of movement.

That's what currently works on my latest layout and did so on the previous one, same DC on both layouts. Even my tiny SW-8 and 0-6-0 negotiate that DCC without problems, and it's DCC-friendly with no modifications or added feeders, just fed from eight rail ends.
 

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Discussion Starter · #4 ·
Yes in both scenerios

Yes my layout plan has a paralel dual main line where there are double cross overs and there shouldn't be any need for any special wiring outside of the frog as the polarities shouldn't cross!

HOWEVER there is one in the center of the layout where it is in the middle of a Dog Bone style reverese loop and I was recomended an auto reverser on each side of it at least as far in so that the loco clears the crossover...I think a foot on each side is good...with main bus feed to the X and like I said reverser loops after that on each side

That makes sense that one decoder would flip all 4 motors for a double cross as you either want it crossed or staright with one command...I guess you just wire all four motors to the lead coming form the decoder then.

Its getting clearer as I go and will be fun to get it all up and running!

Thanks Again
Ron
 

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Ron

Double crossovers can have simple wiring,
or they can create reverse loops. It depends
on how they are used in the layout. I can't
picture your layout's use of the crossovers and
reverse loop from your description.

We could do a much more informative response
to your questions if you could provide a simple
drawing or photo of your entire trackplan.

Don
 

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Then, yes, you do have the completion, or closure, of a reversing loop there, and not a double main...if you mean the central DC. The three on the outer main do simply service parallel mains.

If you opt for a digital reverser, and I would recommend that you do for ease of 'fun', it would be powered from your bus, just like the rest of the layout components, but its output would serve only the loop to the right, and you would either gap or use insulated joiners at the exits toward the loop. Also, for simplicity, you would run trains that fit entirely within the confines of the gapped loop.
 

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Discussion Starter · #8 ·
Then, yes, you do have the completion, or closure, of a reversing loop there, and not a double main...if you mean the central DC. The three on the outer main do simply service parallel mains.

If you opt for a digital reverser, and I would recommend that you do for ease of 'fun', it would be powered from your bus, just like the rest of the layout components, but its output would serve only the loop to the right, and you would either gap or use insulated joiners at the exits toward the loop. Also, for simplicity, you would run trains that fit entirely within the confines of the gapped loop.
Yes that sounds good...there are 5 double X actually on the outer tracks, 3 up front and one on each end but YES they do service paralel tracks...The only other one is on the ORANGE loop which indeed is a reverse loop where the train can change direction if wanted...

Yes it is DCC (ESU Ecos) and for a reverser I am going to use a PSX-AR and a Hex frog juicer to make them right. Do I have to worry about the frogs on the other switches IE polarity when they switch....The turnouts i am getting are the NEW PECO "Unifrog" medium ones which are both insulfrog if you just leave it OR electrofrog if you hook up the wire...which ever you chose to do...

So you are saying only one insulated reversing loop to the right of the orange X crossover then...Not one on each side of the crossover?

Ideally i'd like to be able to have the trains go around all sections of tracks both ways...Am I off or lost on this or should it be possible? How about the the fiddle yard up top..It's more of a staging yard but if I get a train turned around on the orange loop then it'll come into the yard from the opposite way...Is this going to work or be OK>>?

Do I need those Bus Snubber things at the ends of the bus line?

thanks for your help!!!
Just learning all this stuff.
Ron
 

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Ron

The double crossovers at the bottom of your
layout do not present a reverse loop situation.
No insulated joiners needed with them.

However, the double crossover in the middle (orange or
brown which ever it is) does create TWO reverse
loops. You would connect the double crossover
to your main power bus. Use Insulators to create
an isolated section on both ends of the double
crossover. Use insulated joiners at every point
where EITHER reverse loop connects thru a turnout
to the main. You will need two reverse loop
controllers. One for each loop.

Don
 

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Discussion Starter · #12 ·
Ron

The double crossovers at the bottom of your
layout do not present a reverse loop situation.
No insulated joiners needed with them.

However, the double crossover in the middle (orange or
brown which ever it is) does create TWO reverse
loops. You would connect the double crossover
to your main power bus. Use Insulators to create
an isolated section on both ends of the double
crossover. Use insulated joiners at every point
where EITHER reverse loop connects thru a turnout
to the main. You will need two reverse loop
controllers. One for each loop.

Don
Don on the cross overs that are not reverse loops just normal wiring do I have to send power to the frogs or not. if I do I probabaly will just use a frog juicer but asking if I need to do this.
Thanks
 

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I have not used these double crossovers in the 'non reverse
loop' situation you have, but I doubt
that you will need do any special wiring for them. When
you get them 'temporarily' installed you can then
test and know for certain.

Don
 

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Discussion Starter · #14 ·
I have not used these double crossovers in the 'non reverse
loop' situation you have, but I doubt
that you will need do any special wiring for them. When
you get them 'temporarily' installed you can then
test and know for certain.

Don
OK Don I will try it then. They sure are expensiv for a little piece of track over 100.00. Then you need 4 motors underneath to drive it from the comand centre LOL

Ron
 
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