Wait, it works if you go around the loop, but not if a southbound train crosses over to the north main to run against the normal flow of traffic?
I'm pretty sure the gaps are NOT in the correct place for that track arrangement. The gaps should be all the way to the right, after the last crossover, so the loop end is isolated, and that gets powered by the AR-1.
Here's why. Trace yoiur path around if a train on the south main crosses to the north main and then goes around the loop onto the south main - not the bypass. You now have red touching blue (or green, depending on colors in photo of layout or colors of actual wires underneath) - and since both north and south main are fed by the output of the AR-1, it's a short that cannot be corrected.
See everyone pooh-pooh'd my idea of just isolating the end loop for simplicity, but it IS much simpler to do that if there is any sort of crossovers or whatnot in the middle of a dogbone shape, than to try to block off both necks of the dogbone.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
rrinker Briefly short then and see if the AR-1 clicks.
Briefly short then and see if the AR-1 clicks.
Haven't tried this yet but I can say that the AR1 is clicking when the train crosses the turnouts so I guess that it is working. I wonder if I got the gaps wrong. Do I need to gap the turnouts?
trafficdesign rrinker Briefly short then and see if the AR-1 clicks. Haven't tried this yet but I can say that the AR1 is clicking when the train crosses the turnouts so I guess that it is working. I wonder if I got the gaps wrong. Do I need to gap the turnouts?
Which turnouts does it click on? The northbound, the southbound, or the crossovers?
rrinker See everyone pooh-pooh'd my idea of just isolating the end loop for simplicity, but it IS much simpler to do that if there is any sort of crossovers or whatnot in the middle of a dogbone shape, than to try to block off both necks of the dogbone. --Randy
This may very well be the next thing that I try as this electrical stuff is slowly zapping my newfound love of the 'world's greatest' hobby.
I believe Rich solved your problem 6months ago
richhotrain I read through this thread very quickly, so I may be forced to retract everything that I am about to say. But I only see a need for one AR-1. First of all, you need gaps between the connecting turnouts of each crossover. That will prevent shorts caused by reverse polarity. Now, each mainline can operate straight through without any difficulty. However, as soon as a train crosses over from one mainline to the other mainline, a short will occur. To prevent a short, place gaps further up and down on the left side mainline, far enough apart so that the entire longest train is inside the gaps. The reversing section becomes the left mainline between those gaps on the mainline and the gaps dividing the crossovers. The green circles represent the gapped rails. So, only one AR-1 is needed. Use Atlas turnouts if you can because they are already gapped and they are not power routing. If you use Peco turnouts, use Insulfrogs since they are already gapped, but they are power routing, so additional feeders may be needed to avoid dead sections of track. Avoid Peco Electrofrog turnouts if at all possible. I have nothing against Electrofrogs, but they do require more gapping and more wiring. To wire the AR-1, run a pair of feeders from the bus wires to the input side of the AR-1. Any and all feeders from inside the reversing section should be connected to the output side of the AR-1. No feeders inside the reversing section should be connected directly to the bus wires. No feeders from outside the reversing section should be connected to the AR-1. Rich
I read through this thread very quickly, so I may be forced to retract everything that I am about to say.
But I only see a need for one AR-1.
First of all, you need gaps between the connecting turnouts of each crossover. That will prevent shorts caused by reverse polarity.
Now, each mainline can operate straight through without any difficulty. However, as soon as a train crosses over from one mainline to the other mainline, a short will occur. To prevent a short, place gaps further up and down on the left side mainline, far enough apart so that the entire longest train is inside the gaps. The reversing section becomes the left mainline between those gaps on the mainline and the gaps dividing the crossovers. The green circles represent the gapped rails.
So, only one AR-1 is needed. Use Atlas turnouts if you can because they are already gapped and they are not power routing.
If you use Peco turnouts, use Insulfrogs since they are already gapped, but they are power routing, so additional feeders may be needed to avoid dead sections of track. Avoid Peco Electrofrog turnouts if at all possible. I have nothing against Electrofrogs, but they do require more gapping and more wiring.
To wire the AR-1, run a pair of feeders from the bus wires to the input side of the AR-1. Any and all feeders from inside the reversing section should be connected to the output side of the AR-1. No feeders inside the reversing section should be connected directly to the bus wires. No feeders from outside the reversing section should be connected to the AR-1.
Rich
This may no longer be true with the track plan modifications.
BMMECNYC I believe Rich solved your problem 6months ago
I thought so too... but it doesn't work. The pic you posted wouldn't work as the distance between the crossovers is only a couple of feet. So we came up with a new idea and that is what I am having trouble with.
BMMECNYC trafficdesign rrinker Briefly short then and see if the AR-1 clicks. Haven't tried this yet but I can say that the AR1 is clicking when the train crosses the turnouts so I guess that it is working. I wonder if I got the gaps wrong. Do I need to gap the turnouts? Which turnouts does it click on? The northbound, the southbound, or the crossovers?
The crossovers click multiple times when I go from north to south. This is odd as the AR1 documentation clearly says that "it should not trip more than once when the train is in the reversing loop."
When I run straight through from south all the way thru the south main bypass and out the north main all is well. It's when I try to cross over from North back to South that I get the fatal short that will not reverse itself.
rrinker I'm pretty sure the gaps are NOT in the correct place for that track arrangement. The gaps should be all the way to the right, after the last crossover, so the loop end is isolated, and that gets powered by the AR-1. Here's why. Trace yoiur path around if a train on the south main crosses to the north main and then goes around the loop onto the south main - not the bypass. You now have red touching blue (or green, depending on colors in photo of layout or colors of actual wires underneath) - and since both north and south main are fed by the output of the AR-1, it's a short that cannot be corrected.
Alton Junction
trafficdesign The crossovers click multiple times when I go from north to south. This is odd as the AR1 documentation clearly says that "it should not trip more than once when the train is in the reversing loop."
Another reason could be incompatibility between the AR-1 with its mechanical relay getting overmatched by solid state electronics elsewhere on the layout.
A third reason could be a faulty or malfunctioning AR-1.
Bernard, how long is the train that you are running through this reversing section? Is it longer than the reversing section?
richhotrain Not if he wired it the way we told him to, and the photo he took of the AR-1 shows that he wired it correctly. The North and South Mains are wired in phase between the gaps. So, the AR-1 should reverse the polarity in your scenario and avoid a short. Rich
Not if he wired it the way we told him to, and the photo he took of the AR-1 shows that he wired it correctly. The North and South Mains are wired in phase between the gaps. So, the AR-1 should reverse the polarity in your scenario and avoid a short.
The only power going to the gapped (or reversing) section are the two sets of feeders shown in the AR1 photo and I used the red rear convention for both the north and south mains in the gapped section.
Rest of the layout is wired red outside rail and blue/green inside rail.
richhotrain Bernard, how long is the train that you are running through this reversing section? Is it longer than the reversing section? Rich
Just running a loco thru causes the short. Train length doesn't seem to matter. I tried running a trackmobile and the minute the wheels bridged the right gap on the South Main it shorted and did not reset.
richhotrain rrinker I'm pretty sure the gaps are NOT in the correct place for that track arrangement. The gaps should be all the way to the right, after the last crossover, so the loop end is isolated, and that gets powered by the AR-1. Here's why. Trace yoiur path around if a train on the south main crosses to the north main and then goes around the loop onto the south main - not the bypass. You now have red touching blue (or green, depending on colors in photo of layout or colors of actual wires underneath) - and since both north and south main are fed by the output of the AR-1, it's a short that cannot be corrected. Not if he wired it the way we told him to, and the photo he took of the AR-1 shows that he wired it correctly. The North and South Mains are wired in phase between the gaps. So, the AR-1 should reverse the polarity in your scenario and avoid a short. Rich
How can it reverse the polarity when both tracks are coming from the output of the same AR-1? Because if you look at the picture of the AR-1, both the North main and South main are fed from the output of the AR-1.
richhotrain A third reason could be a faulty or malfunctioning AR-1. Rich
I am going to go and pick up a new AR1 tomorrow to rule this out as right now this seems like the most likely possibility.
trafficdesign richhotrain A third reason could be a faulty or malfunctioning AR-1. Rich I am going to go and pick up a new AR1 tomorrow to rule this out as right now this seems like the most likely possibility.
Incidentally, what happens if the loco moving from left to right on the South Main tries to exit the reversing section by crossing the gaps on the right just before the South Main Bypass joins the mainline track?
rrinker How can it reverse the polarity when both tracks are coming from the output of the same AR-1? Because if you look at the picture of the AR-1, both the North main and South main are fed from the output of the AR-1.
richhotrain Incidentally, what happens if the loco moving from left to right on the South Main tries to exit the reversing section by crossing the gaps on the right just before the South Main Bypass joins the mainline track? Rich
Hmmmm....seems to short out here as well. However, the funny thing is that this short seems to be more 'intermittent'. The only way I can describe it is that sometimes the polarity is such that it makes it through and sometimes it is not.
I wish I could be more scientific but this has me completely baffled.
trafficdesign richhotrain Incidentally, what happens if the loco moving from left to right on the South Main tries to exit the reversing section by crossing the gaps on the right just before the South Main Bypass joins the mainline track? Rich Hmmmm....seems to short out here as well. However, the funny thing is that this short seems to be more 'intermittent'. The only way I can describe it is that sometimes the polarity is such that it makes it through and sometimes it is not. I wish I could be more scientific but this has me completely baffled.
I stayed out of this thread...simply because I'm a believer of too many hands in the pot..spoil the soup. But now I'm curious. Do You run the same kind of equipment through the reversing section each time when it shorts? I say this because you say the short is intermittent. Is it possible that metal wheel sets are bridging your gaps sometimes and creating the shorts? It's possible.
Take Care!
Frank
You want the wheels to bridge the gaps so that the auto-reverse unit senses a short and flips the polarity of the rails to correct the situation.
Assuming that the OP has wired the reversing section correctly, and it appears from his photo that he has wired it correctly, either the gaps are not open sufficiently or the AR-1 is malfunctioning.
Since he is using plastic rail joiners, my guess is that the gaps are open sufficiently.
So, I suspect that the AR-1 is malfunctioning. It could be that the TTC adjustment simply needs to be set correctly. If the TTC is adjusted correctly, then either the AR-1 is faulty or there is a solid state electrical component such as a circuit breaker interfering with the operation of the mechanical relay on the AR-1.
The OP may want to confirm that he is using Atlas Custom Line turnouts and manual ground throws. At least that was the case back in January.
Good morning!
richhotrain So, I suspect that the AR-1 is malfunctioning. It could be that the TTC adjustment simply needs to be set correctly. If the TTC is adjusted correctly, then either the AR-1 is faulty or there is a solid state electrical component such as a circuit breaker interfering with the operation of the mechanical relay on the AR-1.
I am building a reverse loop this morning exactly like the one in the AR1 instructions and will know soon. Have tried the TTC adjustment at every setting changing the adjustment 1/4 turn at a time with no effect whatsoever.
richhotrain The OP may want to confirm that he is using Atlas Custom Line turnouts and manual ground throws. At least that was the case back in January. Rich
Yes that is still the case.
Rich,
I know about this part:
But what about the metal wheel sets on the cars after the polarity has been set....would that not trip the AR again, appearing to work intermittently, when the wheels bridge the gaps? especially if they are right across from one another, the gaps should always be staggered, I was taught.
zstripe But what about the metal wheel sets on the cars after the polarity has been set....would that not trip the AR again, appearing to work intermittently, when the wheels bridge the gaps? especially if they are right across from one another, the gaps should always be staggered, I was taught. Take Care! Frank
Good idea to stagger the gaps! I wonder if that might be something to test and see if it makes a difference. AR1 test of reverse loop will be completed this AM and we will have another piece of the puzzle...
zstripe what about the metal wheel sets on the cars after the polarity has been set....would that not trip the AR again, appearing to work intermittently, when the wheels bridge the gaps? especially if they are right across from one another, the gaps should always be staggered, I was taught.
what about the metal wheel sets on the cars after the polarity has been set....would that not trip the AR again, appearing to work intermittently, when the wheels bridge the gaps? especially if they are right across from one another, the gaps should always be staggered, I was taught.
I never intentionally stagger gaps on reversing sections, but I suppose that they might be staggered anyhow because I do not consciously attempt to align them perfectly. Digitrax is silent on the matter, but the instruction sheet for the PSX-AR suggests a 1/8" stagger, stating that perfectly aligned gaps may reduce the current needed for the PSX-AR to reverse properly. Dunno, maybe staggering gaps would make a difference.
But, what troubles me is the multiple clicks that the OP is hearing. That indicates that the AR-1 is constantly sensing mismatched polarities. I still wonder if the OP has any solid state components (e.g., a PSX circuit breaker) elsewhere on the layout that is overwhelming the mechanical relay on the AR-1.
richhotrain But, what troubles me is the multiple clicks that the OP is hearing. That indicates that the AR-1 is constantly sensing mismatched polarities. I still wonder if the OP has any solid state components (e.g., a PSX circuit breaker) elsewhere on the layout that is overwhelming the mechanical relay on the AR-1. Rich
Nothing else except a Zephyr extra and a UT4 throttle.
trafficdesign BMMECNYC I believe Rich solved your problem 6months ago I thought so too... but it doesn't work. The pic you posted wouldn't work as the distance between the crossovers is only a couple of feet. So we came up with a new idea and that is what I am having trouble with.
Read the pg 9 of the PSX-AR instructions for having a reversing section shorter than the train length.
here:
http://dccspecialties.com/products/pdf/man_psxar.pdf
EDIT: And even that note says that extra gaps may be required. I am a firm believer that the train length reversing section is a holdover from the days of manual reversing loops, and aren't required anymore, just recommened. I could see that the arguement could be made that lighted passenger cars may cause the reversing section to short or cycle excessively, but that has not been my experience.
Someone may correct me if im wrong but that should work as well.
I still contend the the reversing section does not have to be longer than the train. I have run 30ft long trains through a 3ft reversing section (metal wheels) without issue. (I do not know which reverser is installed on that particular club module.
BMMECNYC Read the pg 9 of the PSX-AR instructions for having a reversing section shorter than the train length. here: http://dccspecialties.com/products/pdf/man_psxar.pdf Someone may correct me if im wrong but that should work as well. I still contend the the reversing section does not have to be longer than the train. I have run 30ft long trains through a 3ft reversing section (metal wheels) without issue. (I do not know which reverser is installed on that particular club module.
I had been a huge fan of the Digitrax AR-1 for years, having installed five of them on my layout to deal with multiple reversing sections. But, when I decided to add PSX circuit breakers and divide my layout into a series of separate power districts, I suddenly had no end of problems with the AR-1's. So I replaced all of them with PSX-AR units.
The AR-1 needs fine adjustments to the TTC screw to permit trains longer than the reversing section. A loco or consist with metal wheels needs to be shorter than the reversing section. Lighted passenger cars need to fit inside the reversing section as well. A lighted caboose needs to fit inside the reversing section as well. Unlighted passenger cars with metal wheels may or may not cause problems if the entire train is longer than the reversing section.
My recent experience is that the PSX-AR is more tolerant when it comes to unlighted passenger cars with metal wheels. But the loco consist still needs to be shorter than the reversing section itself.
I have a number of Walthers passenger cars that are set up for lighting, but I run them without any lighting attachments. But the metal pickup plate for the lighting is enough to affect even the PSX-AR if the entire train is longer than the reversing section.
Prudence dictates that the reversing section be long enough to accommodate the longest train using the reversing section. The OP indicates that this is the case on his layout.
Here is what the PSX-AR manual has to say:
The length of the reversing section of track between the gaps should generally be longer than the longest train that will use the section of track.
It's not a holdover. If you have success with a less than train length reverse section, then you are not running loco consists longer than the reverse section, or are not using lighted passenger cars. Unless you cut gaps with laser-guided 1/10000 of an inch precision, they will never be exactly parallel and it will be very unlikely that the distance between the sets of gaps is enough to allow multiple metal wheels to exactly touch all the gaps at the same time. SO in a sense, it does work. But try building a loco consist longer than the reverse section, or jsut have 2 independent locos and try to cross both sets of gaps at the same time. It won't work - it CAN'T work because the reverser would have to set the phase of the reversing section in both directions at the same time.
richhotrain Here is what the PSX-AR manual has to say: The length of the reversing section of track between the gaps should generally be longer than the longest train that will use the section of track. Rich
Cut and pasted from further on in the PSX-AR manual
If your train is longer than your reverse block and has metal wheels, you may need to cut additional gaps into the reverse section. Simply cut another set of gaps at both ends of the reverse sections inside of the original gaps. The distance between these gaps and the original gaps should be longer than the wheelbase of any metal truck. Note that one end of the reverse section will be aligned with normal polarity track power while the opposite or other end will have a polarity mis-match and require the reverser to act.