Thanks, Rich. I have decided to go the way my schematic diagram shows.
The area west of the wye may be busier than you think once everything is built. But that area is probably a couple of years away. I am just now doing the final design of the wye area, and the detailed track plan will be updated to match my schematic. Also, the yard and industrial areas will be designed.
Again, thanks everyone for your input.
Doug, the reversing section on the main line is not a poor choice. It's just that there are various locations where the reversing section can be isolated, and that west leg of the wye and the stub track staging looks to be a less busy area in that full track plan and, as such, a better choice for the reversing section.
If you choose to place the reversing section in the area that you colored in red, that will work just fine.
The double crossover does not pose a problem because the track rails are all in phase. It does not create any reverse polarity problems.
If you gap the section of track colored in red, then the track north and west of the wye does not require any special gapping.
Your latest track diagram appears to differ with the larger, more detailed track plan in at least one respect. I am referring specifically to the track running diagonally to below the west leg of the wye.
Rich
Alton Junction
I appreciate each argument.
Although the wye area tracks had been tentative, they are now finalized. Please refer to the last schematic I posted (which hasn't changed):
https://www.dropbox.com/s/1v3ih2uhryq324n/wye_schematic_revised.jpg
The double track main line to the west of the wye is an active main ending in a stub yard. Trains will be simultaneously passing each other at the double crossover. The double crossover and other track work on the west side and north sides of the wye concern me - where would gaps go? These are my concerns for using the west side for the auto-reverser.
Putting the auto-reverse section on the east side seems simpler. I do not want the auto-reverse block to be the full length of the east leg. I just want it to start at the diverging points of the upper-right turnout.
I do not fully understand why having the auto-reverse section in the main line is a poor choice. Yes, through trains will exist. At this location, only one train may enter it at a time (unless I want a cornfield meet). Since the wye is a busy area, there will be no more or less action to trigger the auto-reverser than anywhere else on the wye.
I will be using an all-electronic auto-reverser, so action will be fast and there will be no arcing.
I have to go to Boston Oct. 18 through Oct. 20. I will be able to reply to this thread through Oct 17 and will guarantee any further replies Oct. 21.
Texas Zepher But still the entire area to the "west wing" of the wye is stub ended in staging, right? I would make that entire area the "block" controlled by the auto-reverser. It is not an issue how many locomotives are withing the trackage, it only matters if multiple locomotives would be simultaneously crossing in-or-out of the controlled section.
But still the entire area to the "west wing" of the wye is stub ended in staging, right? I would make that entire area the "block" controlled by the auto-reverser. It is not an issue how many locomotives are withing the trackage, it only matters if multiple locomotives would be simultaneously crossing in-or-out of the controlled section.
TZ makes a good point here.
If you consider the entire track diagram rather than the abbreviated drawing that the OP provided in his first link, it does make more sense to isolate the entire west wing of the wye. I got lazy the first time around and just viewed the first track diagram which had already been posted. That red line approach would work, but as TZ suggests you are messing with the main line if you do that. The entire east side of the wye is actually part of the main line. The entire west side of the wye is not more than a connection to stub end staging.
Incidentally, the abbreviated track diagram does not accurately portray the west side of the wye on the full track diagram.
My question becomes - which will see more traffic/trains? Presumably the main would, and as TZ says, it would be better to put the auto-reverse on the "stub" end of the wye ... or in your case, the "branch" end of it. I would give consideration to my previous suggestion, putting the autoreverse on the east leg of the wye, but extend the reversing section (electrically) further down the branch to "one train length".
Brad
EMD - Every Model Different
ALCO - Always Leaking Coolant and Oil
CSX - Coal Spilling eXperts
Hmmm, I think that will work. I just bothers me that there is a "main" on both sides of the reversing loop section. That means a train just rolling through on the main could (well more than could - will) trip the reverse function. That is also why I disagreed with the three people who liked the idea of using that sort section of the wye (the original diagram with the red section in it). That was on the main. Flip flip flip constantly. Electronically it is always better to isolate the stub end of a wye.
It is also interesting that this is a dog bone main. That complicates things even more.
I am not certain the best solution might not be to add 2 or 3 more auto-reversing units.
I don't know why my image didn't embed in the post. I have redone the schematic anyway to show the suggested auto-reverse block for the wye, as well as the two return loops at the end of two of the wye branches.
Unfortunately, the diagrams do not show up. You may want to try again.
Did you mean to say west of the wye for the return loop?
The advantage of making the reversing section just longer than the longest train is that you can limit the possibility of more than one train simultaneously entering and exiting a reversing section which would cause a short. The longer the reversing section, the greater the possinbility of simultaneous train entry and exit.
The main line east of the wye does not cross the other tracks at grade.
The main line east of the wye does terminate in a return loop that is already controlled by an auto-reverser. I am now thinking that the whole main in that direction can be considered a leg of the wye? See below.
Or else just make it the length of a train? Are there pros and cons?
Again, thanks for all the advice.
I am assuming that, as you move northeast out of the east leg of the wye, those three crossings are elevated and do not cross the mainline at grade level.
If you extend the reversing section onto the main line east of the wye, you need to gap the stock rails on the west end of the turnout above the wye. Then you add the third set of gaps far enough east down the main line to accomodate the longest train.
As far as multiple trains running through or above the wye, there is a physical limit as to how many can operate simultaneously in that area. For that reason, the reversing section that is being proposed in this thread will operate efficiently without concern for tripping the auto-reverser in more than one direction.
I see no issue with extending the east leg to "train length", I would probably gap the track beyond the turnout (so that the turnout maintains polarity with the "main" track and not the east leg of the wye). Electrically speaking, it would not change the schematic I suggested, even if the leg was train length.
K.I.S.S. - Keep It Simple, Silly
I didn't think it would be this easy. However, I may extend the red branch further east to accommodate a train length rather than incorporate the turnout. A train on the north track could span that upper right turnout. Is it OK if that happens? I have to decide my most likely operational scenarios.
Thanks to all.
There could be situations where more than when train will move in or out of the 'west' section simultaneously, i.e.. coming from the east and south. So, I think I will be going with isolating the east branch of the wye.
I agree as well.
You will also need an auto reverser on the loop at Coldwell.
Martin Myers
twcenterprises Any reason you can't just wire up the section I've highlighted in red as your reversing section? Brad
Any reason you can't just wire up the section I've highlighted in red as your reversing section?
I agree with Brad on this one. That area of track colored red is all that is needed to isolate a reversing section. If that area of track is not long enough to accomodate the entire train, you can always extend the area of the reversing section to include the LH turnout above that leg of the wye plus some of the track to the right of the turnout. In that case, you would increase the number of pairs of rail gaps from 2 to 3 to completely isolate the larger reversing section.
Thanks for the clickable links.
I took the liberty of making your links clickable.
Dr. Frankendiesel aka Scott Running BearSpace Mouse for president!15 year veteran fire fighterCollector of Apple //e'sRunning Bear EnterprisesHistory Channel Club life member.beatus homo qui invenit sapientiam
I have planned a junction incorporating a wye that will include a passenger station. The schematic is shown at
https://www.dropbox.com/s/s4eqt953g4udz2y/Y%20Schematic.jpg
This is for N-scale with DCC. Multiple locomotives would be within the wye trackage area at one time.
I plan to use one or more PSX-AR Auto Reverser / Circuit Breakers from DCC Specialties to automatically control track polarity. How should this be wired?
You can see the full proposed track plan at
http://klrr.dkjones.net/html/all_in_one_view.html
The track plan in the wye area is a little different than the schematic.