Our club is developing a 2-section reverse loop with the attached track plan. It consist of a 2 ft. X 2 ft. connecting module and a 4 ft. X 4 ft. Module with a passing siding. My question is will this require two reversing modules or will one do the job. I'm having a bit of a hard time understanding this and I'd appreciate anyone's help. Thanks, Don Sent from my VS985 4G using Tapatalk
Am assuming that the two main lines come together, somehow, to the left of the questionable town? If not, there is no reversing in play. You could isolate the tracks before the two switches on the left, that way everything to the right, including the switches reverse at the same time. The problem is that this module is large enough, it is conceivable to have trains coming and going through both the upper and lower switches at the same time, a no-no for reversing sections. Or you could isolate the double mains from the left hand river at the top of the 4x4 to somewhere to the left of the agricultural area at lower left. This would then require two reversers, one for each main.
We always run trains in one direction, counter-clockwise. The town module has insulated rail joiners on both ends of the loop, completely isolating it from the module that it connects to. Does that mean that our switching, complicated as it is, could be handled with a single reversing module connected between the power bus and a point between the insulated rail joiners and before the first switch on the town module? Sent from my VS985 4G using Tapatalk
Unless the electrical conflict is out of the picture, I see no (electrical) reverse loop. It's more like 2 balloon tracks, with inner loop a secondary, switcher's drill track, which serves industry spurs via the three switches/turnouts, so as to not foul the (outer) main line during said work..
The direction of running has nothing to do with a reverse loop (nor where isolation and auto-reversing occurs). It is about the electrical polarity (cue the Third Doctor shouting "reverse the polarity"). As Mark says and I tried to above, the only thing which can cause what you have shown to be a reversing loop is if there are interchange connections between the upper and lower tracks on modules to the left of "Town?" or if the tracks are both wired the same polarity. The real question then is "how are the other modules wired?" For a simple two-track module, is the upper rail of each track "black" and lower "red"? If yes, then this new module would be a reverser. If so, then follow either of the solutions given above. Personally, I would go with the (albeit more expensive) 2 auto-reverser solution.
I had to jump in again.. If you unfold the curved track making it all a straight path (the way a dispatcher's control panel would look) you'd have a main line thru-track with one spur off it and a secondary track coming off of the main and returning to it at the other end, below and parallel to it, with 2 facing and trailing point spurs (depending on from which direction a, say, road switcher enters it...Period ! What's all the gibberish about a reversing module, at least electronically ?! What's out of the picture frame is what could/would determine any polarity conflicts. Simply put: What is shown here are 2 parallel tracks with spurs coming off them. Then the only question is, will your modular club want to incorporate this particular end module. ..M
Looking at that graphic, it is pretty simple. Assume it runs east/west. The North and South rails stay constant, therefore, no conflict. Put a crossover in the upper left between the mainlines and we have conflict, reversing switch, AR1, all that good stuff.
Thanks Rick, To attempt to clarify, our club's DCC modules are wired similar to N-track, but with only two tracks rather than three. Rails from front to back are AB, AB, where A is + and B is -. We have a loop at each end To try and clear things up, this is a reversing loop, one of two on opposite ends of a modular layout, similar to N-Trak, but with only tracks rather than the standard three tracks on N-Trak. Each of the red lines on the sketch represents two rails. Furthermore, as with N-Trak, from front to back, the rails are AB, AB, or +-, +-. (the two outside rails are opposite polarity and the two inside rails are opposite polarity. That is why a reversing module is required. There are insulated rail joiners connecting the tracks on the upper left (town ? module from the module to its left. There is a power bus that connects all of the modules electrically. My confusion arises from some people telling me that I need two reversing modules in order for this to work and my understanding that only one is required. Don
Thanks, Don. That does clarify. You COULD get away with just one auto-reverser, with the entire section from just before both of the switches. As I said up above, that could be dangerous, since there may be a real chance for a train to be exiting and entering this large loop at the same time. That will cause the auto-reverser to go into a conniption fit. Shortening the reversing section can reduce this issue, but then requires two.
Thanks RBrodzinskt, We experience a DCS100 shutdown of our current Digitrax AR1 and MRC AR522 reversing modules when two trains simultaneously bridge the insulated gaps between the loops and theircadjacent modules. This is something that we have just learned to live with and try to avoid. Even when the entire layout consisted of a single block, the DSC100 always safely shut down the layout until one train was physically pulled past the insulated joiners. Since we broke the layout into multiple blocks protected with an NCE CP6/6-zone circuit protectot, when the short occurs, the loop zone's light comes on with simultaneous shutdown of the loop block, and the rest of the layout chuggs merrily along. All that said, the above is the case with our simple loops with no turnouts. Would there be any difference with the complicated switching and ridings of our new loop? Thank a bunch, Don
Don, nope, no difference. Look at it as if you just have a long siding, with other spurs, coming off a single main.
That's exactly what I'm trying to get across !! It's a main line bent, what ?, 190 deg. into a horse shoe with a siding and spurs coming off them..It doesn't reverse the track polarity anywhere, if that's what the OPer is concerned about..
Mark, pay attention. It was clearly explained 5 posts up that this constitutes a reversing loop because the polarity of the tracks that enter in the diagram’s upper left are the same: + on north rail, - on the south for each track. The comment above, which is true for what you say, is meant to clarify for Don that this giant loop doesn’t change how it will react any differently than how their other simpler loops act. There is simply more “stuff” on this loop.
Thanks again for the evaluation. The lady who is building this loop and I were wondering about the pros and cons of 1 single reversing module as compared to 2, one for the upper side and one for the lower side. As a checked on my understanding of it, Could you critique my explanation to her: "I'm not absolutely positive, but I don't think that a DCC train that is already in the loop wouldn't be afected by the second train entering the loop other than, if it is in motion, being stopped by the action of the circuit protector on the block. Of course, if 2 reversing modules were used, one for the upper loop and one for the lower loop, it would be unlikely that annything less than a dead short derailment would shut down the block under any circumstances." Don Sent from my VS985 4G using Tapatalk
Please strike the word "don't" in the first line of my last post. Sent from my VS985 4G using Tapatalk
RBrodzinsky, why do you say "Mark, pay attention" ? I am paying attention ! I was agreeing with you. That's why I said "That's exactly what I'm trying to get across !!" I.E. What you just said... Other than that I've no idea if Donstaff's modular club does or doesn't want this modul to be incorporated. And yes, if a crossover is added to the converging main at upper left of picture, or out of picture, there will then be an electrical reverse-polarity loop to be dealt with..M
Don, I have marked in blue where you need to gap if you use one reverser, and in yellow where you should gap if using two. Each track would have its own reverser. To answer the question, atrain fully inside the loop will not be affected by another one entering or exiting the loop. The only time there will be a problem is if two are crossing the gap at the same time. The odds of this happening will be reduced in the two reverser scenario, you just have to evaluate exactly where to gap.
