# Wiring a double loop layout



## Mannix (10 mo ago)

Hello,
I want to build a double loop layout (like this one below) but I have no idea how I can wire it up in DC. Thanks for your help.


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## Dennis461 (Jan 5, 2018)

Like this...brown indicates insulated gaps in rail


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## Dennis461 (Jan 5, 2018)

I have a similar layout, my center section looks like this


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## mesenteria (Oct 29, 2015)

What makes this more than just two reversing loops (each of which must be isolated from the center turnout complex, as Dennis shows) coming together and being innocuous as they meet at a crossing, like two loops meet in a Figure-8, is that each loop meets on itself, at its own insertion...IOW, at a turnout. So, each turnout must be powered separately from the loops, themselves, again clearly showing in Dennis' diagramme. This is what the two outward pairs of brown gaps signify. But now you're stuck with a long unpowered length between two turnouts unless the turnouts can power the segment between them. So, you power that complex, the crossing/crossover turnouts and their joining segment, AS ONE. Clearly shown that this can be done safely and effectively in Dennis' drawing.
So, two loops, separately powered, and a middle portion that would need to be reversed itself if there's a conflict on either end with the power in the crossover complex. What I would do is wire both gapped loops to the same bus component, meaning their left and right rails are jointly powered in either phase or polarity. Then, simply control the crossing. You need one DPDT there since there's no conflict in that geometry.


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## timlange3 (Jan 16, 2013)

mesenteria said:


> What makes this more than just two reversing loops (each of which must be isolated from the center turnout complex, as Dennis shows) coming together and being innocuous as they meet at a crossing, like two loops meet in a Figure-8, is that each loop meets on itself, at its own insertion...IOW, at a turnout. So, each turnout must be powered separately from the loops, themselves, again clearly showing in Dennis' diagramme. This is what the two outward pairs of brown gaps signify. But now you're stuck with a long unpowered length between two turnouts unless the turnouts can power the segment between them. So, you power that complex, the crossing/crossover turnouts and their joining segment, AS ONE. Clearly shown that this can be done safely and effectively in Dennis' drawing.
> So, two loops, separately powered, and a middle portion that would need to be reversed itself if there's a conflict on either end with the power in the crossover complex. What I would do is wire both gapped loops to the same bus component, meaning their left and right rails are jointly powered in either phase or polarity. Then, simply control the crossing. You need one DPDT there since there's no conflict in that geometry.


No, you will need 3 dpdt electrical switches and 3 isolated sections as Dennis461 shows. This way you can enter either loop on either route.


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## traction fan (Oct 5, 2014)

Dennis461 said:


> Like this...brown indicates insulated gaps in rail
> 
> View attachment 580436


If you leave out the two turnouts, and simply have a short stretch of double track where the turnouts are on your original plan, things will be a whole lot simpler electrically. (Two wires from the power pack to the track) What purpose do the turnouts serve in your plan?

Traction Fan 🙂


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## kilowatt62 (Aug 18, 2019)

traction fan said:


> If you leave out the two turnouts, and simply have a short stretch of double track where the turnouts are on your original plan, things will be a whole lot simpler electrically. (Two wires from the power pack to the track) What purpose do the turnouts serve in your plan?
> 
> Traction Fan 🙂



By using two turnouts, the loops can be entered Either clockwise or, counter clockwise. Also said at the end of post #5.


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## mesenteria (Oct 29, 2015)

timlange3 said:


> No, you will need 3 dpdt electrical switches and 3 isolated sections as Dennis461 shows. This way you can enter either loop on either route.


You can do that in the way I described. Pick a direction, whichever loop you wish to start in, clockwise or no, and all you have to do is switch the middle turnouts, and then only if there's a conflict in phase or polarity coming up.


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## Mannix (10 mo ago)

Many thanks for all very helpful replies folks. But It's a lot more complicated than I thought...


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## J.Albert1949 (Feb 3, 2018)

My opinion only, but that's a very poor plan.

It's essentially _"two reversing loops"_ connected end-to-end.

In DC, you're going to need two "reversing sections" and you're going to be throwing double-pole, double-throw switches almost continuously just to keep a train running without shorting out.

You'd do better with a modified "dog-bone" plan that eliminates the switches (at least to start out with).

Best to go "back to the drawing board" and start over with this one...


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## RedJimmy1955 (Aug 23, 2021)

I was thinking the same thing as JAlbert1949......yes indeed! When I was investigating 2 rail O Guage as a layout...a Capital Trackers fella drew me almost the same DPDT ideas, and claimes it C O U L D work....BUT!!!!! J. Alberts' advice is spot on. Try another layout design


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## Mannix (10 mo ago)

J.Albert1949 said:


> My opinion only, but that's a very poor plan.


You're absolutely right !


J.Albert1949 said:


> You'd do better with a modified "dog-bone" plan that eliminates the switches (at least to start out with).


Very good idea !


J.Albert1949 said:


> Best to go "back to the drawing board" and start over with this one...


I'm on it !


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## traction fan (Oct 5, 2014)

kilowatt62 said:


> By using two turnouts, the loops can be entered Either clockwise or, counter clockwise. Also said at the end of post #5.


killowatt62;
So what? Its still an unrealistic, round & round, loop; plan. Of course he can do it that way if he want's to, but I don't feel that being able to run the same loop in the opposite direction is worth the extra wiring needed, or the possible derailment issues with some turnouts. What does he really gain, in terms of operating interest, over the simpler "squeezed oval"
I suggested? It gets the wiring down to two wires from the power pack to the track, and apart from the direction change, is pretty much the same layout. Up to the OP of course. I was simply trying to recommend a simpler version. Judging by his last response, simpler might be what he prefers.

Traction Fan


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## mesenteria (Oct 29, 2015)

I need to correct myself: I forgot that this is a double loop, *I think meaning twinned tracks running parallel*? If so, then yes, this becomes somewhat more complex. If it's just two loops facing each other as I think the diagramme shows, then it's as I describe, a simple reversible series of turnouts between two isolated loops, both of which can be wired parallel to each other using the same bus. But, if you have twinned tracks comprising each loop, you'll need to join them at some point, requiring additional gaps and perhaps more reversing...I haven't figured it out. Sorry for my confusion...the most easily managed and cheapest to build would be single track loops.


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## kilowatt62 (Aug 18, 2019)

traction fan said:


> killowatt62;
> So what? Its still an unrealistic, round & round, loop; plan. Of course he can do it that way if he want's to, but I don't feel that being able to run the same loop in the opposite direction is worth the extra wiring needed, or the possible derailment issues with some turnouts. What does he really gain, in terms of operating interest, over the simpler "squeezed oval"
> I suggested? It gets the wiring down to two wires from the power pack to the track, and apart from the direction change, is pretty much the same layout. Up to the OP of course. I was simply trying to recommend a simpler version. Judging by his last response, simpler might be what he prefers.
> 
> Traction Fan



“Who cares?” You do apparently.
You asked the question, “what purpose do the turnouts offer?” 
I gave an answer in earnest. No malcontent inferred. That is all. No big deal. Cool your jets. 😉


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## Mannix (10 mo ago)

Thanks for all your reply folks.


traction fan said:


> Its still an unrealistic, round & round, loop; plan


 That the reason why I cancelled this silly project.


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## Mannix (10 mo ago)

But I found a very interesting solution: *REV2 Autoreverser (DC & DCC)*


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## Conductorkev (Nov 5, 2021)

Mannix said:


> But I found a very interesting solution: *REV2 Autoreverser (DC & DCC)*



X2 as there are 2 reverse loops.


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## Mannix (10 mo ago)

Works fine for two loops (see page 3): 
*DC AUTOREVERSER WITH POINTS CONTROL REV2*


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## Conductorkev (Nov 5, 2021)

Mannix said:


> Works fine for two loops (see page 3):
> *DC AUTOREVERSER WITH POINTS CONTROL REV2*



That will only control one of the loops need 2 of them


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## JeffHurl (Apr 22, 2021)

Couldn't you get by with just one AR module if you used it to control the short section between the 2 loops? Assuming the train could only be so long anyway... Seems like it would work. In any event, the train would have to be really short anyway...


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## Conductorkev (Nov 5, 2021)

JeffHurl said:


> Couldn't you get by with just one AR module if you used it to control the short section between the 2 loops? Assuming the train could only be so long anyway... Seems like it would work. In any event, the train would have to be really short anyway...


Possibly but you would just run the engine......


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## Mannix (10 mo ago)

Maybe I better use a diamond crossover to solve the problem. What do you think about it ?


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## DonR (Oct 18, 2012)

A double crossover would still create two reverse loops and
require either one or two reverse loop controllers depending
on how long is the track between the two loops. If long enuf
to hold the longest lighted passenger train you could get
by with one as suggested by Jeff, otherwise you would need two reverse
controllers.

The better solution would be to use a simple crossing. It
doesn't create any reverse loop and it permits continuous
running without throwing points

Don


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