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Wye and Loop Gaps for Reversing on DCC

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Wye and Loop Gaps for Reversing on DCC
Posted by Future4oo0 on Tuesday, November 13, 2018 3:49 PM

Hello all! 

I am nearly ready to wire but I am still a bit confused on the reversing section wiring and gaps for DCC. Images are at the link below. For the WYE where should I gap and where do I place the AR1?

For the reverse loops since the outside loop does back on itself where do I gap? Also AR1’s

Wye & Loop Album Link: https://imgur.com/a/Kt8yVMq 

Thank you!

Andrew 

Tags: DCC , reverse loop
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Posted by BigDaddy on Tuesday, November 13, 2018 4:06 PM

I'm still learning about where to gap, but here is your layout:

 

This should work for your wye. 

https://dccwiki.com/Reverse_Sections

I think you are saying the outside loop, loops back on itself.  I'm not sure that is visible in this photo.

Imgur photos in your album, have a BB link,either at the top right or the right of the picture (depending on what view of your pics you are in)  Copy the BB link and post it directly with control V, do not use the photo icon.

Henry

COB Potomac & Northern

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Posted by Future4oo0 on Tuesday, November 13, 2018 4:58 PM

WyeLabeled the sides in blue and red to make it easier to see

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Posted by Future4oo0 on Tuesday, November 13, 2018 5:02 PM

Outside loop coloringOutside loop coloring

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Posted by Future4oo0 on Tuesday, November 13, 2018 5:06 PM

Inside loop coloring

Inside loop coloring cross over is at the 3 way turnout

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Posted by Future4oo0 on Tuesday, November 13, 2018 5:06 PM
Added more photos to clarify.
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Posted by peahrens on Tuesday, November 13, 2018 5:39 PM

Andrew, I'll leave the specific recommendations to others here who are more expert than I.  My layout just has a reversing loop at each end.

But you may find the following website (Reversing Sections topics), while detailed, is very informative and a place to learn the ins and outs.  You will note that in some cases there are options, as well as considerations such as train length, etc. 

http://www.wiringfordcc.com/track_2.htm#c4

 

 

Paul

Modeling HO with a transition era UP bent

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Posted by Future4oo0 on Tuesday, November 13, 2018 6:10 PM

peahrens

Andrew, I'll leave the specific recommendations to others here who are more expert than I.  My layout just has a reversing loop at each end.

But you may find the following website (Reversing Sections topics), while detailed, is very informative and a place to learn the ins and outs.  You will note that in some cases there are options, as well as considerations such as train length, etc. 

http://www.wiringfordcc.com/track_2.htm#c4

 

 

 

 

Do your reverse loops loop back upon themself so a single train let’s say loops around and come back on the same track in enter the loop on? Cause mine would exit on a different track? 

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Posted by richhotrain on Tuesday, November 13, 2018 8:23 PM

Future4oo0

WyeLabeled the sides in blue and red to make it easier to see 

The red and blue lines drawn on your photo are not entirely accurate. As you look at the photo, the turnout on the right side leading into the wye is the opposite polarity to the leg of the wye to which the turnout connects. In other words, red meets blue and blue meets red at that connection point. So, as you propose to wire your layout, the rail connections at that point need to be gapped. And, since the tail of the wye connects to more track and not a stub end spur, the tail of the wye needs to be gapped. Lastly, to fully isolate the reversing section, you would need to add gaps on the other turnout that leads into the wye, the turnout just outside the left side of your photo.

One other consideration is the length of the longest train that will be running through the wye. To avoid shorts, the isolated (gapped) reversing section should be longer than the longest train. That would require a different gapping configuration than the one proposed here.

Rich

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Posted by richhotrain on Tuesday, November 13, 2018 8:26 PM

Regarding the two loops, can you take a photo from above the point where the two loops fold back onto themselves? From the photos that you provided, it is difficult to determine where the points of reverse polarity occur.

Rich

Alton Junction

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Posted by BigDaddy on Tuesday, November 13, 2018 9:00 PM

Future4oo0

Outside loop coloringOutside loop coloring

Unless there is something else happening out of the picture, the track coming out of the tunnel and the track approaching the loop ought to be the same polarity.

At the highest redline in the photo, there appears to be a single crossover, which makes the loop a reversing loop.  I don't see that the three way turnout plays a roll. 

If I am stating that correctly, the tunnel track should be red on the right instead of blue and should be gapped before it reaches the loop turnout.  The left side of the loop, from top down, should be gapped after the crossover and after the triple turnout.

Edit

OR on the right side, start the reversing loop after the tunnel track meets the loop

Don't cut any gaps until someone confirms or disproves my hypothesis.

 

Henry

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Posted by Future4oo0 on Tuesday, November 13, 2018 9:48 PM

Rich! Thanks I do have some lighted passenger coaches so what you are saying is that I will need to gap out further due to them and the longest train I plan to run. How far do I gap out on the right and left sides? 

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Posted by Future4oo0 on Tuesday, November 13, 2018 9:50 PM

This is the best photo I have atm, traveling atm.

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Posted by Future4oo0 on Tuesday, November 13, 2018 9:52 PM
Yes, that is correctly regarding the tunnel I reversed them.
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Posted by richhotrain on Tuesday, November 13, 2018 11:33 PM

Future4oo0

Rich! Thanks I do have some lighted passenger coaches so what you are saying is that I will need to gap out further due to them and the longest train I plan to run. How far do I gap out on the right and left sides?  

The first diagram below shows your proposed wiring protocol. My drawing is turned upside down from yours, but you get the idea. The arrows point to the opposite polarities that force a reversing section.

My suggestion is to wire a portion of the mainline track above the wye the opposite of the rest of the mainline track so as to match the left side of the wye in my diagram. Then, gap as shown in the second diagram in order to provide a length necessary to accommodate your longest train.

Rich

wye-2.jpg

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Posted by richhotrain on Wednesday, November 14, 2018 5:00 AM

Future4oo0

This is the best photo I have atm, traveling atm. 

That latest photo helps, but it is still difficult to grasp the various connections and what happens with your track work outside of the photo. So, let me take a shot at this.

As I see it, the outside loop would not be a reverse loop except for that pair of crossovers before the outside loop. To simplify the wiring, I would treat the outside loop as a reverse loop and gap it as such. So, you would install gaps just beyond the crossovers on both ends of the outside loop. If you do that, you would then need to wire the two crossovers to match the polarity of each crossover with the connecting "mainline" tracks so that trains using the crossovers will not short. Somewhere down the mainline (outside of the photo) you may run into another reverse polarity situation, and that situation would need to be dealt with. Is the overall layout a "dogbone"? In other words, is there a loop at the other end?

Regarding the inner loop, as I see it, the two diverging legs of the 3-way turnout form the inner loop. Is that correct? If it is correct, then you would simply gap the the two divergent ends of the 3-way to form an isolated reverse loop.The sidings that form off the straight end of the 3-way would be unaffected by the reverse polarity issue on the inner loop. However, since the tail of the 3-way connects to the outer loop, the sidings that form off the straight end of the 3-way would have the same polarity as the outer loop.

Lastly, that tunnel track would need to be dealt with since the outside loop is a reverse loop. If you gap the divergent side of the turnout that leads toward the tunnel, that would be sufficient to keep the tunnel track out of the outside reverse loop.

Your main concern with this track configuration is the possibility of one train entering the outer loop as another train is exiting the outer loop. The inner loop is of no concern in this regard since simultaneous entry/exit would cause a collision between the two trains.

I should note that this suggested arrangement is just one way to do it. There are other ways, but I will leave it to others to suggest alternative arrangements. Perhaps there is a better way to do it, but this is one way.

Rich

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Posted by BigDaddy on Wednesday, November 14, 2018 6:51 AM

I edited my post re: the 3 way turnout.  Rich and I are on the same page.

Henry

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Posted by Future4oo0 on Wednesday, November 14, 2018 6:59 AM

For the Wye thank you very much would it be possible to reverse the space for the Gap to the right side in the photo as I have more room on that side? If not I will make it work. Based on your proposal I believe I would need to gap the red lines. The blue line would be a gap if I reversed it. 

Is that correct?

Also  working on getting a better photo of the loops for you now. 

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Posted by Future4oo0 on Wednesday, November 14, 2018 7:15 AM

More Loop Photos

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Posted by Future4oo0 on Wednesday, November 14, 2018 7:16 AM

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Posted by BigDaddy on Wednesday, November 14, 2018 7:31 AM

A photo and a diagram 180 degrees out of phase is the quickest way to lose me.  So I will avoid saying anything that might be wrong about the wye.

When we discuss layouts, the layout gurus caution agains S curves.  You have S curves on the limb of your Wye parallel to the edge of the layout

II have an S curve, but it is not a problem, but I model a branch line with short cars.  I do not know if this will be an issue for you or not.  Also, the AR1 does not play nice with the PSX circuit breakers. 

Henry

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Posted by Future4oo0 on Wednesday, November 14, 2018 7:57 AM

Hasn't cause a problem yet, when I hooked up some wires just to test it all out. But only time will tell. Did you have a suggestion as to how to fix it? Or just leave it alone? 

Thanks! 

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Posted by BigDaddy on Wednesday, November 14, 2018 10:38 AM

I do not.  Cuyama is one of the layout gurus, but I've never seen him post in an electrical thread.  You might start a separate thread and ask for others experiences.

I am envious of the space you have to work with.

Henry

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Posted by richhotrain on Wednesday, November 14, 2018 10:50 AM

Future4oo0

For the Wye thank you very much would it be possible to reverse the space for the Gap to the right side in the photo as I have more room on that side? If not I will make it work.

For the wye, you could use the right side for the extended reversing section, but it gets more complicated because the tail of the wye would now be reverse polarity where it connects to the next section of track. That wouldn't be so much of a problem to gap beyond the tail of the wye but for that crossover. So, preferably you would want to use the left side of the wye to extend the reversing section.

Rich

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Posted by richhotrain on Wednesday, November 14, 2018 10:59 AM

BigDaddy

A photo and a diagram 180 degrees out of phase is the quickest way to lose me.  So I will avoid saying anything that might be wrong about the wye.

Henry, how about this?

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Posted by BigDaddy on Wednesday, November 14, 2018 11:31 AM

richhotrain
Henry, how about this?

Better

Apologies to Andrew, but if I don't express my ignorance, I won't know any better.

richhotrain
My suggestion is to wire a portion of the mainline track above the wye the opposite of the rest of the mainline track so as to match the left side of the wye in my diagram.

I don't have a handle on the track plan, but what if it's all mainline?  In other words, there is no dead end spur.  Doesn't wiring 2 portions of the mainllne differently create a reversing problem beyond the area we can see in the photos?

Henry

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Posted by Future4oo0 on Wednesday, November 14, 2018 11:48 AM

 Track plan 1 

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Posted by Future4oo0 on Wednesday, November 14, 2018 11:48 AM

 Track plan 2

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Posted by richhotrain on Wednesday, November 14, 2018 11:48 AM

BigDaddy
 

I don't have a handle on the track plan, but what if it's all mainline?  In other words, there is no dead end spur.  Doesn't wiring 2 portions of the mainllne differently create a reversing problem beyond the area we can see in the photos?

As long as the reversing sections are fully gapped and therefore isolated, there shouldn't be a problem. However, somewhere down the mainline (outside of the photos we are seeing), the OP may run into another reverse polarity situation, and that situation would need to be dealt with. It would really help to see photos or diagrams for the entire layout. Is the overall layout a "dogbone"? In other words, is there a loop at the other end?
 
Rich

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Posted by Future4oo0 on Wednesday, November 14, 2018 11:49 AM

 Track Plan 3

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