alloboard Is there a jolt .........when a locomotive crosses the insulated gap from the short circuit district to the reversing district?
Is there a jolt .........when a locomotive crosses the insulated gap from the short circuit district to the reversing district?
alloboard, I am still not clear what the difference is between a "short circuit district" and a "reversing district". But I assume that you are referring to a locomotive crossing from the main section of the layout into the reversing section.
If the locomotive is sparking and jerking, it sounds like it is shorting but still moving which tells me that the loco is moving so fast that the system recovers in time to prevent a dead short.
What is actually happening on your layout? Is a short occurring? What happens if the loco is moving slowly as it crosses the gaps from the main section into the reversing section?
Rich
Alton Junction
It is an electrical occurrence such as sparkingand jerking. A short circuit district is a district created by a Digitrax PM42 to manage short circuits or auto reversing.
Still wondering what a jolt is, and what the OP means by short circuit district.
Assuming the AR1 or PM42 is set correctly, or you flip the DPDT BEFORE the loco hits the gaps, no, there should not be any real noticeable jolt. If you creep over the gap with an autoreverser in use, there might be a slight hesitation. With a DPDT switch, there should be absolutely none, ever, because you are just crossing over gaps with the correct polarity on either side. Another plus for the idea of changing the polarity via a relay controlled by the switch motor (a couple of circuits for this have been posted ont he Digitrax Yahoo group - does need a switch motor like a Tortoise though). Rather than first have a problem (a short) which is detected and corrected by the autoreverser, the idea is to never have the short in the first place.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
alloboard Is there a jolt or not on a passing train when DPDT, Digitrax AR1, or PM42 is working at the reverse loop, when a locomotive crosses the insulated gap from the short circuit district to the reversing district?
Is there a jolt or not on a passing train when DPDT, Digitrax AR1, or PM42 is working at the reverse loop, when a locomotive crosses the insulated gap from the short circuit district to the reversing district?
alloboard, I am not clear what you mean by "jolt". Can you explain what you mean by that term?
Is it an electrical occurrence such as sparking, or a physical movement of the loco such as surging or jerking?
Also, what do you mean by the term "short circuit district" as opposed to the term "reversing district"?
I always refer to the areas of the layout as "main section" and "reversing section".
alloboard Thanks for your effort and time you took to draw and simplify the map, very creative. I have completly isolated the loop as indicated in the earlier threads. I am now waiting to wire a DigitraX PM42 that I ordered.
Thanks for your effort and time you took to draw and simplify the map, very creative. I have completly isolated the loop as indicated in the earlier threads. I am now waiting to wire a DigitraX PM42 that I ordered.
While you are waiting for the DigitraX PM42 that you ordered, you could test the setup with a simple DPDT switch.
Rich.
Thanks for your effort and time you took to draw and simplify the map, very creative. I have completely isolated the loop as indicated in the earlier threads. I am now waiting to wire a Digitrax PM42 that I ordered.
Viewing the OP's track diagram is complicated by the fact that it is presented as white on black background, the number of elevated crossings over grade level tracks, and the sheer number of parallel tracks and crossovers.
So, I have prepared an alternative track diagram. Imagine that trains move clockwise, headed east across the top of the diagram, south down the right side of the diagram, west across the bottom of the diagram and north up the left side of the diagram. As the tracks disappear off the right side of my diagram they actually form a continuous loop as seen in the OP's diagram. Likewise, as the tracks disappear off the bottom left side of my diagram they also form another continuous loop as as seen in the OP's diagram.
Since the layout is essentially a continuous loop (a folded dogbone, if you will) with yards and sidings, the tracks headed east are colored in red, and the tracks headed west are colored in black. Although the lines each represent single tracks, think about red as the outer rail and black as the inner rail. If red connects to black, you have a reverse polarity situation. That occurs twice in the diagram, represented by track colored blue. It occurs where the left leg of the wye connects to the track above the wye, and it occurs at the crossover to the left of the wye.
Therefore, the affected track needs to be isolated to create a reversing section. To fully isolate the reversing section on this layout, four sets of gaps must be created, as indicated by the purple lines. The issue here is the length of the reversing section. Of course, if you place the gaps where I indicated, the reversing section is pretty small. The reversing section can be lengthened by moving the gaps further away from the wye as long as the reversing section is fully isolated from the main layout.
As Randy, myself, and others have pointed out, the wiring is crucial to proper performance of the AR-1. The input side of the AR-1 (terminals 4 and 5) must be connected to the main bus wires. Any feeder wires inside the reversing section must be connected to the output side of the AR-1 (terminals 1 and 2). No feeder wires from the reversing section should be connected to the main bus wires.
All the feeders in teh reversing section, between the insulated joiners, must go to the output of the AR1. The rest of the feeders for the layout, you leave alone. The input to the AR1 connects to the main bus coming from your booster.
The overall visual concept regarding the fact that I will install an auto reverser and the existing track feeder wires makes it complicated. I don't know what to do with my existing track feeder wires to distribute power evenly without power loss. In the diagram and the video you will see existing track insulators and the blocks they result in. So what should I do regarding the existing feeder wires. When I install the AR1 or PM42, what should I do about my feeder wires? Should I simply remove or rewire the existing track feeders to accommodate the auto reversing revision installment? We don't want the AR1 district to distribute it's power to other portions of the layout via the existing track feeders that may cause other problems and intermittent movements and operations. The line you were inquiring about is not really an outer main line but a branch line. My layout is in the room of my upper level of my house. The lower portion of my layout runs under my bed! The line that was marked undecided may eventually be re aligned to run out of my room into the hallway forming it's own loop! My layout is based on the inspiration of "Union Interlock" in Rahway New Jersey, except the loop. It's literally a flying junction "where the red marked overpass crossings are" leading to the Interlocking interchange with the crossovers leading to the wye.
Those crossovers connecting your double main line to the lower yard actually result in a reverse polarity situation at two points in the upper right portion of your track diagram. A single AR-1 can deal with the problem by completely gapping the wye and the connection to the wye at the crossover right above the tail of the wye. So, four sets of gaps need to be installed in your track work. The two legs of the wye should be gapped, the center of the crossover just beyond the tail of the wye should be gapped, and just before the beginning of the second crossover beyond the tail of the wye,
The issue here is how long the reversing section needs to be so that it is long enough to avoid having a train entering and exiting the reversing section at the same time. So, you are going to have to consider exactly where your reversing section needs to be gapped and how long the reversing section needs to be.
One curious feature of your track plan is that the double main line is not really a continuous loop. As the double main line continues through the wye, the right leg of the wye carries one main line track into the other main line track at the right hand turnout below the wye. If you trace the double main line around the layout, the outer main line track continues to the left under the wye and then abrubtly ends at the left side of the layout and is marked "undecided".
I thank you all for your help in this thread. As a token of my gratitude I will inform you to check out Model Memories.com, Island Model Works, and Imperial Hobby Productions. The Metroliners are back now from Walthers.com they will start shipping in 2013.
Those other red areas are elevated crossings. I should have made that clearer and pointed it out earlier.
I see. I appreciate your effort in helping me troubleshoot this issue.
An auto-reverser receives its power from the main bus wires. Feeder wires connect from the main bus wires to the input side of the auto-reverser, supplying it with power. The feeder wires from the reversing section connect to the output side of the auto-reverser. The auto-reverser senses a reverse polarity situation and immediately matches the polarities to prevent a short.
Note that the red markings that you see in the middle and lower left of the diagram are not grade crossings but are actually grade separated overpasses. They should not be mistaken for crossovers with wire feeders. Thanks a lot for the reference regarding the gaps and the auto reverser. I have a Digitrax DB150 with a PR3 connected to my PC. I believe that I need the Digitrax AR1. I never really understood how the auto reversing concept worked but I think I understand it better now that I know that I have to gap the whole loop. Does the Digitrax AR1 supply its own power? How does auto reversing work?
Hi!
One thing I would consider doing is everywhere you have a reverse loop, I would insert insulator rail joiners or cut gaps. This will get you to the point that all trackage is powered, and you have no shorts (except when a loco crosses the breaks). Anyway, then - assuming you are in DCC - I would install the reverse loop breakers (forgot the proper name)...................
ENJOY !
Mobilman44
Living in southeast Texas, formerly modeling the "postwar" Santa Fe and Illinois Central
While I was composing my reply, Randy posted his reply. He sees more issues than just the upper right hand portion of your layout.
I think we need more clarification about the other parts of your layout. Are those other red areas crossings or are they elevated sections of track crossing over ground sections of track?
The wye in the upper right portion of your layout, which I have circled in white, is the source of your problem.
It creates a reverse loop which must be isolated and gapped.
You will either need an auto-reverser or a DPDT switch to match polarities.
You've actually got multiple reverse loops there, with all those crossovers. Your best bet to fix the right hand side would be to put gaps in both rails of both tracks of the right-hand loops. One set just ot the left of where the feeder somes in, the other set just to the right of the top right crossover. Both rails, of both tracks. You will need two autoreverses to feed that area, one for each loop.
Then there are 2 more loops on the bottom part, which when combined with the same set of crossovers in the 'yard' part make 2 more reverse loops. Gaps just to the right of where it says "undecided" at the bottom center, and the other set of gaps where the lines are goign strgith up on the far left should make a long enough reverseing section - that's two MORE autoreversers. Or sicne a total of 4 - a single PM42 with all 4 sectiosn set up for autoreversing.
There are probably other ways to handle it, but this is the most obvious, even if not most economical. Yor layout is essentially a dogbone with crossovers in the shank portion, which form reverse loops out of the end loops.
This is the normal diagram below
The diagram below shows the short circuits and feeder wires in red.
I will send a track diagram on my next reply.
alloboard, take this as constructive criticism.
There is too much blurry, jittery video to clearly identify your problem.
It would be much more helpful to see a track diagram.
Yes it is a reverse loop.
Yes indeed it is.
Looking at one of your videos,what you have is a reverse loop. It looks like you have 2 reverse loops. So yes you need at least 2 auto reversers, or simplfy your track. It looks like you have Atlas track code 100. These are insulated frogs and you don't to worry about insulating them. A reverse loop is when a train goes through a turn out one way, continues down the track and comes back the opposite way on the other track hooked up to the same turn out. Joe
HHPATH56Any time you have a "crossover or a run-around" with the frog ends facing each other, you are completing a reverse loop,
The statement "any time" is not accurate. One often needs gaps when connecting turnouts frog-end to frog-end, but not a reverser unless the connection creates a reversing loop elsewhere in the plan. In many cases, it does not.
HHPATH56 The use of "double slip switches" will prevent shorts.
Again, not accurate all the time. One can create reversing loops and shorts by adding double slips, depending on the overall track arrangement.
Layout Design GalleryLayout Design Special Interest Group
HHPATH56Any time you have a "crossover or a run-around" with the frog ends facing each other, you are completing a reverse loop, that requires insulating the turnout with a AR1 Reverse module to prevent a short circuit. The use of "double slip switches" will prevent shorts. Bob Hahn
I don't believe you need a reverse module. I have 3 crossover situations (with curved turnouts) that have one insulated frog opposing one non-insulated frog. I didn't actually cut the gaps as I suggested above but used insulating joiners on those stock rails diverging from the non-insulated frogs. They work. Just make sure the points are set for the direction of travel.
Dante