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DCC Wiring for North to South crossovers

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DCC Wiring for North to South crossovers
Posted by CTConrail on Sunday, December 8, 2019 11:29 AM

So let me start out first by apologizing as I know this answer is out there but after a bit of a search I couldn't find it and with 2 toddlers my hobby time is finite.  I am finally building a layout in N scale which will be DCC. Just starting to lay track. When I left the hobby in the late 90's DCC was not really a thing yet so I am still learning.

My issue/question is on my New Haven Railroad Providence RI layout that I will have a double track main...north and south. The plan has a few crossovers, some double some single. Do I need to use auto reversers to correctly wire these to prevent shorts? The frogs are all plastic as I am using code 80 turnouts and Kato double crossovers. If AR's is the answer and I have a north bound train and send a South bound onto a northbound track what will happen to the northbound train? Do I need to use power blocks or districts to address this?  Pardon my dcc ignorance...i am a novice as I said. Thank you. Oh...I am using a NCE Powercab if that matters...no booster yet but probably in the future.

Thanks

Nick

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Posted by rrinker on Sunday, December 8, 2019 12:47 PM

Do the two mains loop around to connect to one another at the ends, like a dogbone shape? If so, insulate the loops at each end and put autoreversers there. You can then have as many crossovers on the parallel mains without any issues. Just make sure you wire the parallel mains correctly:

----A-----

----B-----

 

----A-----

----B----

and not

----A----

---B----

---B----

----A----

                                      --Randy

 


Modeling the Reading Railroad in the 1950's

 

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Posted by CTConrail on Sunday, December 8, 2019 1:06 PM

rrinker
Do the two mains loop around to connect to one another at the ends, like a dogbone shape?

Yes I am sorry I should have mentioned that. The track plan is essentially a big double track circle and the mains to connect to eachother. So do I need an auto reverser at each crossover or can I use 1 for multiple crossovers. Again pardon my ignorance. And also if the AR switches polarity because a north train is crossing over to southbound what will happen to the train I already have running south on the southbound track? Thanks

 

Nick

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Posted by richhotrain on Sunday, December 8, 2019 1:25 PM

CTConrail
 The track plan is essentially a big double track circle and the mains to connect to each other. So do I need an auto reverser at each crossover or can I use 1 for multiple crossovers.
 

It all depends upon the actual track plan. Can you post a copy of your track plan?

Rich

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Posted by CTConrail on Sunday, December 8, 2019 2:01 PM

Here it is. Please no judgement from anyone on how cluttered it is. I crammed a lot into a small space. The turnout I am starting with is a single and circled in green. It goes between the north and south mains. There is however about 3 more double crossovers and at least 2 more singles that go between mains or from one main to a yard or different tracks in the Union Station area.

Providence Layout

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Posted by BigDaddy on Sunday, December 8, 2019 3:21 PM

I see reversing loops at red arrows A,B,C, but not at your circled track, although I seem to have a problem with the color olive and following the track plan.

Maybe it's all the same reversing loop.   I also see one starting a D

Others may see it differnently, hence the labels.

 

Henry

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Posted by CTConrail on Sunday, December 8, 2019 3:47 PM

BigDaddy

I see reversing loops at red arrows A,B,C, but not at your circled track, although I seem to have a problem with the color olive and following the track plan.

Maybe it's all the same reversing loop. 

 

Correct that part is my actual reversing loop and is all the same loop if you can call it a loop. Just wanted to be able to turn trains in the opposite direction to simulate trains returning from New York or Boston. I actually changed where it starts but that is not reflected in this track plan.

I know I will need an AR1 for the "loop".  The olive section represents the viaduct that used to exist in Providence where Union Station was located. Sorry the color and amount of tracks makes tracks hard to follow in that area.  The reversing loop runs under the viaduct along with part of the main, a change I made that was suggested to me by David Popp and was not how my original plan was set up.

As far as regular crossovers on layout (other than at the reversing loop) I won't need AR1's do I need to insulate the 2 turnouts that I used to make single crossovers?

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Posted by nealknows on Wednesday, December 11, 2019 9:34 AM

If you're referring to the AR1 by Circuitron, that is made for DC only. In DCC I would suggest you use a DCC Specialties PSX-AR where you have your reversing loops. I have many of them and they work like a charm. 

Neal

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Posted by richhotrain on Wednesday, December 11, 2019 11:38 AM

nealknows

I would suggest you use a DCC Specialties PSX-AR where you have your reversing loops. I have many of them and they work like a charm. 

I will second that suggestion. The PSX-AR is superior.

Rich

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Posted by BigDaddy on Wednesday, December 11, 2019 11:46 AM

I don't consider myself the guru on reversing loops and I'm surprised no one else has had anything to say. 

How many PSX-AR's does he need and where should the gaps be?

Henry

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Posted by richhotrain on Wednesday, December 11, 2019 1:19 PM

BigDaddy

I don't consider myself the guru on reversing loops and I'm surprised no one else has had anything to say. 

How many PSX-AR's does he need and where should the gaps be? 

I am usually game to take on reversing section issues, but I took a pass on this one because the drawing that the OP provided is difficult to follow due to the coloring scheme and the apparent complexity of the track work.

Rich

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Posted by rrinker on Wednesday, December 11, 2019 2:51 PM

 The key to gifuring it out is to simplyfy with a schematic type diagram. You can leave out any stud-ended yard or siding tracks.

See here:

http://www.wiringfordcc.com/track_2.htm#a43

The first example is the easiest way to wire a track plan like this. The green ends loops are reverse sections. It doesn;t matter if there are 1, 2, 3, or 10 crossovers in the shank park, there are still only ever 2 reverse loops. 

My planned layout is two decks, with a 2 track helix, the two track main runs twice around the room. At each end there are loops, one on the lower level and one on the upper level, to loop the east main back on the west main. Only those loops will be reverse sections. It won;t matter how many crossovers I put between the mains over the run, none of those causes a short if the loops are used as the reverse sections. Making each crossover a reversing section works electrically, but some of those may be too short, plus if you have 5 crossovers, then you'd need 5 autoreverses, instead of just 2. 

                                       --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by CTConrail on Thursday, December 12, 2019 3:04 PM

 

I won't lie I don't really fully get what you are saying Randy but going off the link you posted I can say that my layout is not a dog bone so it is essentially a 2 track circle with a reverse track. I deleted the viaduct and some other things from the plan to make it easier to follow and took a screen grab with the 2 reverse track turnouts circled in green. My track plan is not ideal but its what I had to do to fit what I wanted into a small space. If anyone sees any other spots that need an auto reverser please let me know. Thanks guys.

Screenshot

Plan

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Posted by richhotrain on Thursday, December 12, 2019 5:12 PM

CTConrail
 

I won't lie I don't really fully get what you are saying Randy but going off the link you posted I can say that my layout is not a dog bone so it is essentially a 2 track circle with a reverse track. 

If anyone sees any other spots that need an auto reverser please let me know.

It looks like a dogbone to me and maybe even a folded dogbone, but that alone doesn't necessarily mean that there is one or more reversing sections or reverse loops in the track plan. There may be or there may not be. The link that Randy provided to the Wiring for DCC website clearly illustrates the two alternatives for isolating reversing sections or reverse loops in a dogbone track plan. 

There is more than one of us who would be willing to analyze your track plan if it weren't for the fact that the track plan as presented is, dare I say, visually intimidating. Randy made a good suggestion when he asked if you could strip away the yards and sidings to present a simplifed plan for analysis.

As I say, there may or may not be one or more reversing sections or reverse loops. Since your computer drawing is difficult to discern, it may require a simplified hand drawn track plan without the yards and sidings. By the way, that Photobucket logo overlay sure does not make the analysis any easier.

Rich

 

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Posted by CTConrail on Thursday, December 12, 2019 6:32 PM

No problem yeah I can strip away the yards and non pertinentm sidings. Shapewise I guess in that sense its somewhat of a dog bone but what I meant was mainline 1 does not connect to mainline 2 at each end in a reversing loop. Instead the 2 mains run all the way around in a circle and main 1 connects back to main 1, main 2 connects back to main 2. Then there are crossovers throughout. Strange on my end I don't see the photobucket overlay. Give me a few and I will re-post it.

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Posted by CTConrail on Thursday, December 12, 2019 6:53 PM

Ok here it is with just about every non pertinent track deleted along with all scenery, labels etcMains only

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Posted by BigDaddy on Thursday, December 12, 2019 8:43 PM

Again, I am still a newbie picking out reversing loops, but at X axis 2.7 Y axis 7.4, the turnout closer to the left side, traveling toward the bottom: if you take the furthest left track and travel downward (left means as you look at the diagram, not from the perspective a train traveling downward)  I see the start of a reversing loop. 

If you take the right path downward, either of to the two outside loops at the bottom right of the diagram meet face to face with the left pathway.

If anyone thinks I'm wrong speak up.  I'm here to learn not to be right.

Henry

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Posted by richhotrain on Friday, December 13, 2019 7:00 AM

Not an easy track plan to trace, looking for reversing sections. There is as much of a chance that I could be wrong as that I could be right. But, here is how I see it.

The track plan is essentially a series of over and under ovals with crossovers here and there. The only reversing section that I see, that is connecting rails of opposite polarity, is at that green circle on the left side of the diagram at the 3' mark. At that location, the innermost track in the right loop folds back onto the outermost track leading into the right loop.

What I would do is isolate and gap the section of track that I colored red, and treat that section of track as a reversing section.

Rich

Conrail.jpg

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Posted by BigDaddy on Friday, December 13, 2019 3:21 PM

BigDaddy
at X axis 2.7 Y axis 7.4,

This one where red meets green

Henry

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Posted by CTConrail on Friday, December 13, 2019 7:25 PM

richhotrain
What I would do is isolate and gap the section of track that I colored red, and treat that section of track as a reversing section.

The track you highlighted is essentially just a passing track/yard lead off of the southbound main. The far left green circled turnout that comes off of that will obviously switch polarity as it goes around the layout and connects on to the north bound main at the other circled turnout. Wouldn't that be better suited as an isolated track with the auto reverser?  Would I need 2 auto reversing units, 1 at each turnout? Pardon the noob questions.

 

Thanks

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Posted by CTConrail on Friday, December 13, 2019 8:53 PM

BigDaddy

 

 
BigDaddy
at X axis 2.7 Y axis 7.4,

 

This one where red meets green

 

So pretty much I was correct then on the turnouts I was thinking? You just extended the red highlighted track up to the very beginning where the northbound passing track starts but do I have to put the auto reversing unit wired to that turnout or can I put it where I circled then left side turnout?

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Posted by rrinker on Friday, December 13, 2019 9:01 PM

 The track between the turnouts is the reversing section, one autoreverser per reverse section. You don't need a reverser for each turnout , just the track connecting them. Insulated joiners go between the turnout and the track that is the reversing section, the turnout itself is electrically part of the track that comes before them.

 It's easiest to visualize the simple example of an oval with two turnouts and a diagonal line through the middle. The digonal track is the reversing sections, the insulated joiners or gaps are cut on the diverging side of each turnout, the turnouts themselves are part of the oval, not isolated from it. The diagonal track is then isolated from the rest of the track because of the gaps, it gets its power from the autoreverse unit.

                                    --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by richhotrain on Friday, December 13, 2019 10:17 PM

I have been taking a closer look at your track diagram, and I think that there is a simpler solution to the reverse polarity issue. Whenever reverse polarity situations occur, there is often more than one way to wire the layout, and the method chosen dictates where to isolate and gap the reversing section. A good example of this is the link provided early by Randy, showing two alternative wiring methods.

In your particular situation, you were pretty close with your track diagram with the two green circles. The section of track between those two green circles could be the reversing section. To accomplish this, you would need to wire the rest of the layout in phase.

For example, looking at the top of your track diagram, there are two tracks, an outer track and an inner track. If you wire both of these tracks in phase, say blue feeder wires on the top rail and red feeder wires on the bottom rail and continue this wiring protocol as you work your way down the layout, the only point of opposite polarity is where the outermost track connects at the green circle on the lower right.

In the track diagram that follows, the section of track colored red becomes the reversing section. You would isolate the reversing section by cutting gaps (or inserting insulated rail joiners) at the turnouts marked by the green circles. One auto-reverser would control that reversing section.

Rich

Conrail.jpg 

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Posted by CTConrail on Friday, December 13, 2019 11:41 PM

Awesome thanks guys! Thats exactly how I will do it then. In my mind I keep wanting to carry over DC wiring methods to this layout as I am as I said a DCC noobie. I will get morr used to it as time goes on. Someone asked me about when I said the AR1. I meant the Digitrax AR1 reversing unit which is what I planned to use.

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Posted by richhotrain on Saturday, December 14, 2019 5:17 AM

CTConrail

Someone asked me about when I said the AR1. I meant the Digitrax AR1 reversing unit which is what I planned to use. 

At one time, I used Digitrax AR1s on my layout, and they worked just fine with my NCE PH-Pro 5 amp system. But, when I later installed solid state circuit breakers to protect power districts, the relay-controlled AR1 proved too slow and incompatible, so I had to switch to the solid state PSX-AR. The PSX-AR is more expensive than the AR1, but it is worth it and the PSX-AR is totally compatible with the NCE Power Cab.

Rich

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Posted by richhotrain on Saturday, December 14, 2019 5:23 AM

CTConrail

In my mind I keep wanting to carry over DC wiring methods to this layout as I am as I said a DCC noobie. I will get more used to it as time goes on.

Wiring a DCC-powered layout with one or more reversing sections is not necessarily complicated, but the wiring protocol needs to be thought out in advance to plan where the reversing section(s) will be and how many reversing sections may be needed. And, the reversing section needs to be longer than the longest train using the reversing section.

Rich

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Posted by CTConrail on Saturday, December 14, 2019 7:49 AM

Ok then I will probably go with that since I only need 1 anyway. Now I just need to figure out if I will need a booster. I have the Power Cab starter set...2 amps. I guess that all depends on how many engines I will run at once i would say probably not more than 8 which is the guideline I saw for N scale for the Power Cab. More than 8 engines will require a booster. A few of my trains will have multiple engine consists though.  Eventually I will probably get one but I am hoping I can get by without it for now. 7.5x9 foot layout but there is a lot of trackage as you all can see.

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Posted by richhotrain on Saturday, December 14, 2019 8:16 AM

CTConrail

Ok then I will probably go with that since I only need 1 anyway. Now I just need to figure out if I will need a booster. I have the Power Cab starter set...2 amps. I guess that all depends on how many engines I will run at once i would say probably not more than 8 which is the guideline I saw for N scale for the Power Cab. More than 8 engines will require a booster. A few of my trains will have multiple engine consists though. 

Just add the NCE SB5 Smart Booster to your NCE Power Cab. If you are going to run 8 locos plus a few more locos in consists, you are going to need more amps.

How far along are you with your track work and wiring?

Rich

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Posted by CTConrail on Saturday, December 14, 2019 8:23 AM

richhotrain
Just add the NCE SB5 Smart Booster to your NCE Power Cab. If you are going to run 8 locos plus a few more locos in consists, you are going to need more amps. How far along are you with your track work and wiring?

No I meant no more than 8 including the trains with multiple engine consists. Probably 2 passenger trains, a 3 engine freight and a switcher so 4 trains and even that will probably prove too much for me to handle at once. I will probably get the SB5 at some point but was hoping to get by without it for a while. I just started laying track last week. Still short on some turnouts so I need those to come in. As far as wiring I have not done any yet. Hoping to run my bus lines after the weekend but I need to go get some 16ga wire.

Honestly it will probably be a bit before track is fully laid. The hidden track under the viaduct needs to be all done with a way to access it for cleaning and derailments before I can build and lay track on the viaduct above.

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Posted by CTConrail on Sunday, December 15, 2019 7:46 AM

Hey quick question for you Rich...I was looking at the picture again and my reversing track that you traced in red. Unfortunately I could only fit 1 reversing track which is off of the southbound main and then ends up connecting back at the north main (which will simulate passenger trains returning from New York City) This may be a dumb question but it won't matter which turnout I use to enter the reversing track and what direction I come from will it? No matter what the AR will switch polarity if needed right? I am just trying to visualize how it will need to be wired.

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