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Where's the short?

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Posted by Gaucho on Wednesday, July 26, 2017 11:55 AM

I do no see any reversing loop. I cannot get an engine to reverse direction regardless of which pass i take. The key , I think, is to recognize that the outer rails of the red and blue tracks and the "inner rail of the yellow track should be the same polarity. I hope this helps.

Moe

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Posted by floridaflyer on Wednesday, July 26, 2017 11:58 AM

For now forget the red/black indicators on the plan. Pick a track and call one rail of that track the "outside" rail, follow that rail with the curser, (when doing this I always repeat "outside" to myself to stay on course) and you will find that the outside rail of the track you are following always remains the outside rail regardless of which way you go.

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Posted by ROBERT PETRICK on Wednesday, July 26, 2017 12:23 PM

gdelmoro

Robert I don't seem to understand, If you look at the wiring there is a short without an AR. Note that that each single line on the drawing represents 2 tracks with one wired to the Black bus wire and the other to the Red. Both mainlines are wired the same with the black and red wired on the same rails throughout the dogbone. Prior to the switch that leads to the center diagonal you can see that the top rails of each mainline connect to the black bus wire and the bottom to the red.  When you pass the switch they are reversed.

Coming around the loop off the top right and then up the diagonal from bottom to top there would be a short since the red feed and black feed would connect to each other.  

The same occurs with the bus connections off the main (top center) the track rails are wired the same as the main (Black on top rail Red on bottom) when it reconnects to the main they cross again with the black connecting to the red. another short.

What am I missing? 

Hey Gary-

I apologize for adding confusion to a discussion that already solved the problem of the OP. And, as it turns out, the problem was not related to the AR at all. It involved those old lighting wires inadvertantly left attached to the rails.

I knew I should not have re-opened the discussion. But I saw something about the track geometry that I found interesting. You are right . . . as things are wired right now, the ARs are necessary to change polarity in the rails. My idea was that if things were wired differently from the start (particularly the two mainlines), you would not need to have installed ARs at all.

It was never my intention to criticize what you did or to somehow impose how I would do things. I never intended to imply you should re-wire anything. It was purely an idea to discuss that track layout geometry and track wiring go hand-in-hand. I'm sorry for the intrusion.

And, while I'm apologizing, I hope Big Daddy Henry doesn't think I'm attacking him. He has always shown patience and consideration toward me.

When I get home, I think I'm gonna ballast track for an hour or so. The self-imposed punishment might do me some good.

Robert

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Posted by floridaflyer on Wednesday, July 26, 2017 12:38 PM

Actually Robert you cleared up a wiring method that required two AR's when in actually none were required. We went off in left field while an actual analysis of the track plan would have come to the same conclusion you did. Well done. (Granted the second diagram didn't help) OP has the option of leaving the wiring as is and use the AR's or changing the polarity of some of the wiring and not use the AR's. His call.  

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Posted by gdelmoro on Wednesday, July 26, 2017 2:20 PM

Thanks for the reply. Wish I would have had this info before I wired the whole layout.

Gary

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Posted by BigDaddy on Wednesday, July 26, 2017 2:21 PM

ROBERT PETRICK
I hope Big Daddy Henry doesn't think I'm attacking him.

Like changing the wiring of the mainline, that thought never crossed my mind.

Gary since you have the mainlines wired and bought the reversers, I wouldn't change the wiring just to make if more ....efficient if that's the right word. 

Finding reverse loops is a challenge to me and I didn't know the a dual frog juicer could serve as an AR.  So I think many of us learned something from the thread. 

Henry

COB Potomac & Northern

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Posted by richhotrain on Wednesday, July 26, 2017 2:27 PM

Wow, this thread has taken all kinds of twists and turns.

If you go all the way back to Gary's initial diagram, he presented a layout with two auto-reversers and the gaps to isolate the two reversing sections controlled by those auto-reversers. That could only mean one thing, and that is that the two mainlines were wired "in phase" with one another. So, the problem was analyzed using that assumption.

If the two mainlines are wired with polarities of one mainline opposite the polarities of the other mainline, then there would not be any reversing sections. But, that was not the situation presented to us.

What we still don't know for sure is which way Gary's layout is wired.

Rich

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Posted by floridaflyer on Wednesday, July 26, 2017 3:08 PM

Rich- the way I see it is that the inner loop is wired opposite of the outer loop thus the need for the AR's. If he changed the phase ( polarity) on the inner loop he would not need the AR's. You are right though, this has been an adventure.

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Posted by richhotrain on Wednesday, July 26, 2017 3:20 PM

floridaflyer

Rich- the way I see it is that the inner loop is wired opposite of the outer loop thus the need for the AR's. If he changed the phase ( polarity) on the inner loop he would not need the AR's. You are right though, this has been an adventure.

 

Well, if you draw the layout as a two-rail diagram, using different colors for each rail, you can find what I call the "points of opposite polarity". These are the points where rails of the opposite color connect. To make those two sections in question into reversing sections, the polarities of the two mainlines must match.

The whole issue of reversing sections, or reverse loops, is interesting and often challenging. As this thread demonstrates, there can be reversing sections - - or not - - depending upon how the layout is wired. And when there are reversing sections, they can be located differently depending upon user preferences.

A double ended dog bone with a center crossover between two mainlines is a good example. Do you treat each end as a reverse loop and wire it up that way using two auto-reversers or do you treat the double mainline as a single reversing section, requiring only one auto-reverser?

As I say, interesting stuff.

Rich

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Posted by floridaflyer on Wednesday, July 26, 2017 3:44 PM

Rich, I just don't see where the rails have a point of opposite polarity. I do see that if you take the rails as marked in the diagram as red and black there will be a point where black meets red. But by tracing one of the rails as  outer, I do not find a point where outer meets inner. And the saga continues   

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Posted by Gaucho on Wednesday, July 26, 2017 4:17 PM

Robert,

Based ont he sketch where you show how you wired each rail you defenetly have a short. However, you probleme will go away if you are able to rewire one of the main lines to reverse the polarity from what you show, not with a reverser but physically. On the other hand, you can use a reverseron the crossover track in the center of the diagram. Please note that your polarity marks,  on the upper left crosover are different on both sides of the curve.

Moe

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Posted by floridaflyer on Wednesday, July 26, 2017 4:31 PM

I agree Moe, change the polarity of the inner loop and the need for an AR goes way. Easier to do the inner loop by itself rather than the outer loop and the tracks marked in blue. Or leave things as they are and use the AR's 

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Posted by richhotrain on Wednesday, July 26, 2017 5:04 PM

floridaflyer

Rich, I just don't see where the rails have a point of opposite polarity. I do see that if you take the rails as marked in the diagram as red and black there will be a point where black meets red. But by tracing one of the rails as  outer, I do not find a point where outer meets inner. And the saga continues   

 

Well, I could be wrong, but as I draw it out with the two mainlines in phase, I see two points of opposite polarity.

Rich

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Posted by gdelmoro on Wednesday, July 26, 2017 5:41 PM

I really hate to ask but does anythint change (Related to the reverse loops) if I add 3 more switches on the upper mainline. 

This is there now but i have not connected the switch machines.

The track going off the picture (bottom right) is the upper loop that comes arround to the ferry yard and the diagonal in the center. On the same level you an see a track curving off to the left toward the top of the pic. That connects to the diagona.  So as you can see there are three turnouts and a crossover.

Gary

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Posted by floridaflyer on Wednesday, July 26, 2017 5:57 PM

Thought I had an answer but think I am wrong so I edited out 

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Posted by gdelmoro on Wednesday, July 26, 2017 6:10 PM

Ha, I could be wrong too!  I don't think there is a short because it was working on the old DC Layout.  Let me check the wiring.

Gary

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Posted by floridaflyer on Wednesday, July 26, 2017 6:15 PM

After rethinking the situation I believe the way you currently have the inner loop wired you would be ok. You have a mixed bag, leave the wiring the way it is and the crossover is fine but the 2AR's are needed. Change the inner loop wiring and the crossover becomes a short and would need an AR and reversing section of some sort,but the other 2AR's are not needed. In my view I would leave the wiring the way it is and use the 2AR's per your original plan.  

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Posted by rrinker on Wednesday, July 26, 2017 6:49 PM

 If that's an Atlas crossover the frogs are all insulated and it should be fine. On looking at the overall plan, is the main line bus lines were swapped on the one loop, then there are NO reverse sections at all. The direction of the train around the loops never changes if you follow it around, it's just that if the red feeder is on the inside of the inner loop, then it needs to be the outside of the outer loop (looking at the top part). There then are no shorts on either of those cutoffs. Unless at some point there are crossovers added between the two loops. Then we are back to actually changing the direction of travel of the train and they will be reverse loops no matter how you wire it.

                             --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 floridaflyer on Wednesday, July 26, 2017 7:00 PM

nm

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Posted by ROBERT PETRICK on Wednesday, July 26, 2017 7:35 PM

rrinker

 If that's an Atlas crossover the frogs are all insulated and it should be fine. On looking at the overall plan, is the main line bus lines were swapped on the one loop, then there are NO reverse sections at all. The direction of the train around the loops never changes if you follow it around, it's just that if the red feeder is on the inside of the inner loop, then it needs to be the outside of the outer loop (looking at the top part). There then are no shorts on either of those cutoffs. Unless at some point there are crossovers added between the two loops. Then we are back to actually changing the direction of travel of the train and they will be reverse loops no matter how you wire it.

                             --Randy

Yes, this pretty much sums up what I've been saying when I butted into this thread. Keep in mind that my idea is only one possible alternative to what the OP could have done differently if he did things differently. I'm not suggesting that he rush in with a broadaxe and make radical changes to his layout. Even if he did, there would almost certainly be trade-offs later on down the line, particularly if he is still adding stuff to his track layout that doesn't yet show up on his trackplan sketches. I would suggest, however, that Gary check each and every one of the red/black dots he uses to identify rail polarity on his sketches. There might be some small little tiny discrepancies.

And to be clear, I have no objections to auto reversers. They are useful and reliable pieces of equipment that are readily available and reasonably priced. I have two on my current layout that I salvaged from my previous layout and from the one before that. I got them from Tony's Train Exchange about 15 years ago, and they work as well today as they did when brand new.

Robert

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Posted by floridaflyer on Wednesday, July 26, 2017 8:03 PM

If the two loops are connected at the top of the photo, I believe that the two loops, being wired opposite, would mean that the crossover would not cause a short but would require the original AR'S in the original positions. If all the loops were wired the same it would cause a short at the crossover but the original 2 AR's are not needed.  OP said the track has been that way and worked with DC. Problem is I'm not sure he and I are talking about the same thing. I'm not set in stone about this theory.

 

doug

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Posted by rrinker on Wednesday, July 26, 2017 9:57 PM

 Adding the crossing just changes where the two 'loops' connect to the main. Instead of <left loop turnout>--<right loop turnout> the crossing just makes it <left loop turnout>---<right loop turnout> if I am reading the plan and seeing the turnout and crossing in the photo correctly. He's using Atlas turnouts and I am assuming an Atlas crossing, which are continuous power straight through each branch. Having the tracks cross with insulated frogs in the crossing changes nothing, the electrical plan is identical with or without the crossing.

 It's tricky because in neither case do the loop tracks cause the train to reverse direction of travel ON THE SAME MAIN. However, a train running left to right on the inside loop taking the track diagonally down to the right past the ferry yard will end up running right to left - but on the OUTSIDE loop, not the one it left. Likewise, a train going right to left on the outer loop (or - the plan as drawn without the crossing, coming off the right hand single track) going around the left hand singel track will emerge going left to right - but on the INSIDE loop. Without the crossing, the schematic of the 'reversing sections' simply forms a continuous loop. WITH the crossing, it forms a twice around continuous loop - you can;t go from one 'reversing section' to the other, you have to make an extra lap around one of the double track parts to get around to the second single track part because of the crossing.

 The overall plan is just a figure 8 with two cutoffs that are NOT reversing. Unfold it and draw it out (although it makes the cutoff tracks really awkward looking - but in a schematic who cares if it looks like a 2" radius curve.

Now if there are any other crossovers between the two mains - then yes, you end up with reverse loops, but if the only two connections between the double mains are those outside cutoff tracks, there are no reverse loops and it's all just a matter of wiring the main line feeds the right way 'round and it will work with no reversers. 

                         --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 DSchmitt on Wednesday, July 26, 2017 10:05 PM

rrinker
Now if there are any other crossovers between the two mains - then yes, you end up with reverse loops, but if the only two connections between the double mains are those outside cutoff tracks, there are no reverse loops and it's all just a matter of wiring the main line feeds the right way 'round and it will work with no reversers.                           --Randy

I spent hours drawing arrowsand + signs  on copies of the plan to finally figure that out.  Funny how such a simple plan can be so complicated to figure out the wiring. 

I tried to sell my two cents worth, but no one would give me a plug nickel for it.

I don't have a leg to stand on.

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Posted by richhotrain on Thursday, July 27, 2017 4:40 AM

DSchmitt

 

 
rrinker
Now if there are any other crossovers between the two mains - then yes, you end up with reverse loops, but if the only two connections between the double mains are those outside cutoff tracks, there are no reverse loops and it's all just a matter of wiring the main line feeds the right way 'round and it will work with no reversers.                           --Randy

 

I spent hours drawing arrowsand + signs  on copies of the plan to finally figure that out.  Funny how such a simple plan can be so complicated to figure out the wiring. 

 

It's not complicated if you draw it as a two-rail track diagram and use a different color pencil or pen for each rail. When you do that, you can spot a short wherever two sections of track join with rails of opposite colors.

Rich

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Posted by floridaflyer on Thursday, July 27, 2017 8:32 AM

Randy, using the photo that the OP provided as a reference ( photo is about 12 posts back), at the top of the two straightaways there are two LH turnouts that appear to connect the two loops. They are located next to a visable coil of white wire to the left of the turnouts. These turnouts are not shown on any plan diagram. Question,  if, I repeat if, this is the case and the two loops are wired opposite, it would not cause a short? But if both loops were wired the same it would cause a short?  OP has said that the turnouts have been there for a while and worked on DC. 

But given the twists and turns of this thread, I'm not really sure of anything. 

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Posted by gdelmoro on Thursday, July 27, 2017 10:56 AM

richhotrain

Wow, this thread has taken all kinds of twists and turns.

If you go all the way back to Gary's initial diagram, he presented a layout with two auto-reversers and the gaps to isolate the two reversing sections controlled by those auto-reversers. That could only mean one thing, and that is that the two mainlines were wired "in phase" with one another. So, the problem was analyzed using that assumption.

If the two mainlines are wired with polarities of one mainline opposite the polarities of the other mainline, then there would not be any reversing sections. But, that was not the situation presented to us.

What we still don't know for sure is which way Gary's layout is wired.

Rich

 

 

BOTH Main Linse are wired the same. I followed the MR recommendation of taking an old box car and painted a Black mark on one side and a Red mark on the other to make sure I had the correct rails connected to the correct Bus wire.  If you look at the original layout schematic you can see that both Mainlines follow the same wiring scheme. The same rail on both Mainlines connects to Black and The same rail on both mainlines connects to Red.

Maybe I don't understand what's being asked?

Gary

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Posted by richhotrain on Thursday, July 27, 2017 11:21 AM

Gary, back on Saturday when I first read your initial post and saw that very first diagram, I drew the track diagram as a two-rail diagram, using red for one rail and blue for the other rail. I assumed without thinking further about it that both mainlines were wired the same way (in phase with one another). When wired that way, there are two reversing sections.

After this thread took an entirely different turn, suggesting that there were no reversing sections, I went back to my two-rail diagram and reversed my assumption as to one of the mainlines. Wired that way, there are no reversing sections.

If you have solved your problem and eliminated any shorts, then I don't really see any need to continue this thread. 

Rich

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Posted by floridaflyer on Thursday, July 27, 2017 11:28 AM

Gary, that is not true, the inside loop is wired opposite of the outer loop, thus the need for reversing sections, If both loops were wired the same there would be no need for two reversing sections. While I have you, are the two loops connected at the top of the layout by turnouts that are not on the schematic? Your photo shows two LH turnouts at the top of the straightaways located next to a coil of white wire, are these a connection between loops?  

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Posted by floridaflyer on Thursday, July 27, 2017 11:44 AM

richhotrain

Gary, back on Saturday when I first read your initial post and saw that very first diagram, I drew the track diagram as a two-rail diagram, using red for one rail and blue for the other rail. I assumed without thinking further about it that both mainlines were wired the same way (in phase with one another). When wired that way, there are two reversing sections.

After this thread took an entirely different turn, suggesting that there were no reversing sections, I went back to my two-rail diagram and reversed my assumption as to one of the mainlines. Wired that way, there are no reversing sections.

If you have solved your problem and eliminated any shorts, then I don't really see any need to continue this thread. 

Rich

 

[quote user="richhotrain"]

Gary, back on Saturday when I first read your initial post and saw that very first diagram, I drew the track diagram as a two-rail diagram, using red for one rail and blue for the other rail. I assumed without thinking further about it that both mainlines were wired the same way (in phase with one another). When wired that way, there are two reversing sections.

After this thread took an entirely different turn, suggesting that there were no reversing sections, I went back to my two-rail diagram and reversed my assumption as to one of the mainlines. Wired that way, there are no reversing sections.

If you have solved your problem and eliminated any shorts, then I don't really see any need to continue this thread. 

Rich

It's the other way around Rich. If the loops are in phase no reversing sections are required, As they are wired opposite, two reversing sections are required. There are no reversing sections and if the wiring on the inside(Robert's yellow loop) were reversed the whole layout would be in phase. The need for the reversing sections is caused by the opposite wiring of the orange and yellow loops, there is no reversing of the direction of the loco. I do have another question about the loops connecting but am awaiting more information.
 
 
doug
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Posted by BigDaddy on Thursday, July 27, 2017 12:32 PM

 I was going to end my last post with "Stick a fork in this thread, it is done"  I guess not.

The original sketch showed both mainlines wired in phase and I'm not sure why there is so much uncertainty about that.  

 Robert's scenario was a what if the wiring was different.  I think that has confused some people into stating for a fact that the are wired in opposite phase, they are not.

    Now an insider has revealed that there is secret track we did not know about.  I'm wondering what the guy who is trying to run his HO train with a G scale transformer hasn't told us.

  That piece of track with the rerailer is danger close to the edge of the layout.

 

   

Henry

COB Potomac & Northern

Shenandoah Valley

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