Gaps for DCC are no different than gaps for DC. The difference is that a piece of electronics is swithing polarity.
One thing to remember is that the reverse section (loop or wye) needs to be longer than the longest train. Otherwise, you end up with a train that will reverse the phase as it exits the reverse block while the other end is still entering.
On the wiringfordcc website, a number of the diagrams for wyes show the reverse section on one side of a wye. That only works if the train is shorter than the leg of the wye, not very common. A better arangement is to reverse one tail of the wye. Both wiringfordcc and dccwiki imply that the tail of the wye can't reconnect to the rest of the layout; as long as the tail is long enogh to hold a whole train, the tail will reverse as the train exits the wye.
In the worst case, at least one model of AR (PSX-AR) lets you connect 2 AR blocks together without an intermediate non-reversed block. You just have to adjust the timing so one takes longer to reverse.
Dave Squire
Yes, sorry must have overlooked it, a little tired from all the traveling.
Thank you for all your help!
Future4oo0Any help on the loops now that I added better photos? Thanks for all your help on the WYE
Rich
Alton Junction
Track Plan 3
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?
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?
Track plan 2
Track plan 1
richhotrainHenry, how about this?
Better
Apologies to Andrew, but if I don't express my ignorance, I won't know any better.
richhotrainMy 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.
Henry
COB Potomac & Northern
Shenandoah Valley
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.
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.
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 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.
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.
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!
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.
More Loop Photos
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.
I edited my post re: the 3 way turnout. Rich and I are on the same page.
Future4oo0 This is the best photo I have atm, traveling atm.
This is the best photo I have atm, traveling atm.
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.
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?
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?
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.
Future4oo0 Outside loop coloring
Outside 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.
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.
Future4oo0 Labeled the sides in blue and red to make it easier to see
Labeled the sides in blue and red to make it easier to see
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.
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
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?
Paul
Modeling HO with a transition era UP bent