# Atlas Turnout wiring



## the_train_nut (Feb 14, 2011)

I'm currently building the N scale layout I've always wanted to have in my basement: 40' x 12', based very loosely on the Raritan River Railroad. 

I've already constructed two parallel Code 55 loops to handle two passenger trains -- one in each direction. These loops are powered by separate MRC Railpower 1300 transformers. The power wiring from each transformer is through a double-pole double-throw toggle switch cross-wired to allow reversal of polarity to each track separately -- the loops are each divided into eight separate power blocks with cross-wired DPDT switches to each block. The transformers each have their own reversing switches, but I decided to use the DPDT switches so I could have better control over the various power blocks.

 My problem is this: I have already installed a set of Atlas left-hand turnouts between the two loops and another set of Atlas right-hand turnouts on the other end of the layout. This allows me to crossover from one loop to the other if the need occurs. Track isolators are installed between the two turnouts to prevent short circuits between the two loops when a locomotive is running on each track in opposite directions. Each transformer has a voltmeter installed to supply parallel voltage (positive to positive and negative to negative) to the two track loops, but whenever I try to cross from one track to the other, the locomotive stalls across the turnouts after passing over the isolators. I've measured the voltage across the two tracks of each loop to ensure they are equal and in parallel.

Do I need to totally isolate the sets of turnouts, treating them as a separate power block, or is there another solution available? Do I need to modify the turnouts? If so, how?

Any advice is greatly appreciated!!!!!


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## leftwithnoexits (Jan 22, 2011)

I'm thinking you may have a polarity issues. when your train trys to go onto the other loop, that loop is running in the opposit direction.

I could be wrong as i am sort of a newbie myself.


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## Xnats (Dec 5, 2010)

Does it look something like this? It it does, it should work perfect with a single cab. Using two cabs, you need to throw both at the same time. You said you have the two loops sets to run opposite directions. You would also have to change the polarity on one to match the other on a crossover. That is what I'm thinking anyway, lol. Where's a wiring guru when you need one.


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## the_train_nut (Feb 14, 2011)

Yes, that's exactly the way I have it set up! Because I have two cabs operating independently, I installed cross- wired double-pole double-throw toggle switches between each cab to the track power, with each power supply synchronized in phase when I want to cross over to the other track -- with isolators between the two sets of turnouts. Cross-wired DPDT's allow me to easily change the polarity supplied to the track to which I want the locomotive to cross over. I utilize the center-off position of the DPDT to isolate a particular power block when I want to stop a locomotive but still keep another locomotive on the same track operating. 
The problem occurs when a locomotive tries to cross over the isolators, even though I have identical voltages (measured in parallel by separate voltmeters across the transformers) to the two loops. The only thing I can think of is that the frogs are causing a short circuit across the turnouts when the locos cross over. As long as I don't try to use the crossovers everything is fine.
That's the problem I'm trying to solve.


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## Xnats (Dec 5, 2010)

I'm only guessing with this stuff.
1) Atlas turnouts all have powered frogs I believe. This might be the problem somehow. 
2) If you have both sides insulated, then you had to install a power feed in between. Did you try swapping those leads? 
I'm thinking an overhead picture of two turnouts might help. I tried this set up with kato #6 turnouts and it worked fine, but without DPDT switches. I used two cabs and threw in 2 insulators between the turnouts . Kato #6 turnouts have none power frogs though.


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## the_train_nut (Feb 14, 2011)

"1) Atlas turnouts all have powered frogs I believe. This might be the problem somehow. 
2) If you have both sides insulated, then you had to install a power feed in between. Did you try swapping those leads? "

When you say "both sides insulated," do you mean both tracks of the turnout? I only have isolators installed on the track sections between the two turnouts. I consider everything one one side of the isolators a power block and it is why I use the dpdt switch to supply power to the track. I have the same setup on the other turnout across the isolators. I don't believe it's a matter of swapping leads, as everything works fine until I switch the turnout to the crossover. I also checked polarity with a voltmeter and positive is where I expected it to be. Just to check further, I checked polarity with an LED with an in-line resistor. They need positive directionality, and the LED lights as it should.

I'm thinking an overhead picture of two turnouts might help. I tried this set up with kato #6 turnouts and it worked fine, but without DPDT switches. I used two cabs and threw in 2 insulators between the turnouts . Kato #6 turnouts have none power frogs though. 

Because you used the Kato switches with non-powered frogs, you may have an idea I need to look at!!!!! I also believe the Atlas frogs are powered and that's the original question....

What part of NJ?


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## Xnats (Dec 5, 2010)

the_train_nut said:


> I also believe the Atlas frogs are powered and that's the original question....
> 
> What part of NJ?


Hope you get it solved :thumbsup: seems us N Scaler's are on our own with certain things 
I'm in lovely Brick. Still don't know who would name a town that name. I believe Big Ed is north of me somewhere. He had more snow in January, which in turn, means he moved more snow from one place to another :laugh:


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