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Help with Reversing Loops Please

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Posted by trafficdesign on Thursday, July 24, 2014 6:34 AM

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.

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Posted by richhotrain on Thursday, July 24, 2014 6:07 AM

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.

Rich

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Posted by zstripe on Thursday, July 24, 2014 4:39 AM

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! Big Smile

Frank

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Posted by trafficdesign on Wednesday, July 23, 2014 10:21 PM

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.

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Posted by richhotrain on Wednesday, July 23, 2014 9:31 PM

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.

                

Randy, I am not following you.  Am I misunderstanding his wiring protocol?  The reversing section is both the North and South main lines plus the two crossovers inside those four pairs of gaps.  So, those sections of both mainlines should be wired to the output side of the AR-1.

Rich

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Posted by richhotrain on Wednesday, July 23, 2014 9:27 PM

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.

 

That would be premature.  Check the AR-1 first by creating a short reversing section.

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

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Posted by trafficdesign on Wednesday, July 23, 2014 9:15 PM

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.

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Posted by rrinker on Wednesday, July 23, 2014 9:12 PM

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.

                        --Randy


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by trafficdesign on Wednesday, July 23, 2014 9:10 PM

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.

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Posted by trafficdesign on Wednesday, July 23, 2014 9:06 PM

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 

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.

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Posted by richhotrain on Wednesday, July 23, 2014 9:03 PM

Bernard, how long is the train that you are running through this reversing section?  Is it longer than the reversing section?

Rich

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Posted by richhotrain on Wednesday, July 23, 2014 8:54 PM

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."

Multiple clicks means that the relay on the AR-1 is constantly trying to reset itself.  One reason for that could be the TTC adjustment.  

 

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.

 

Rich

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Posted by richhotrain on Wednesday, July 23, 2014 8:48 PM

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

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Posted by trafficdesign on Wednesday, July 23, 2014 8:21 PM

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.

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Posted by trafficdesign on Wednesday, July 23, 2014 8:17 PM

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.

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Posted by Anonymous on Wednesday, July 23, 2014 8:09 PM

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

 

 

 

This may no longer be true with the track plan modifications.

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Posted by Anonymous on Wednesday, July 23, 2014 8:09 PM

I believe Rich solved your problem 6months ago

 

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Posted by trafficdesign on Wednesday, July 23, 2014 8:04 PM

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.

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Posted by Anonymous on Wednesday, July 23, 2014 8:04 PM

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?

 

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Posted by trafficdesign on Wednesday, July 23, 2014 8:00 PM

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?

 

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Posted by rrinker on Wednesday, July 23, 2014 7:46 PM

 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.

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Posted by rrinker on Wednesday, July 23, 2014 7:44 PM

 One turnout, track looped around from diverging route to straight route. But there's an easier way, just disconnect the output of the AR-1, and attach a couple of short wires. Briefly short then and see if the AR-1 clicks. Do not keep it shorted - if you do, then your booster should trip.

 Or touch the two output wires on the AR-1 to the input. If it doesn't click, try reversing them - one way or the other they will be initially out of phase witht he main bus and the AR-1 will have to flip. If it just shorts and trips the booster no matter what, the AR-1 is probbaly faulty. Turn the trip current to the opposite extreme and try again just to make sure.

                             --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by trafficdesign on Wednesday, July 23, 2014 6:32 PM

richhotrain

Try  setting up a temporary reversing section on a short section of track and run a loco thru it to verify that the AR-1 is working properly.

Rich

 

what would that look like? 

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Posted by richhotrain on Wednesday, July 23, 2014 6:25 PM

Try  setting up a temporary reversing section on a short section of track and run a loco thru it to verify that the AR-1 is working properly.

Rich

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Posted by trafficdesign on Wednesday, July 23, 2014 6:22 PM

richhotrain

 

 
trafficdesign

 

 
richhotrain

Could be a defective AR-1.

How did you make your rail gaps?

Rich 

 

 

plastic rail joiners

 

 

 

 

 

Rich

 

i will check when I get back home. Half time at my sons soccer championships.

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Posted by richhotrain on Wednesday, July 23, 2014 6:19 PM

trafficdesign

 

 
richhotrain

Could be a defective AR-1.

How did you make your rail gaps?

Rich 

 

 

plastic rail joiners

 


And there is a true gap, no rails touching?

Rich

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Posted by trafficdesign on Wednesday, July 23, 2014 6:16 PM

richhotrain

Could be a defective AR-1.

How did you make your rail gaps?

Rich 

plastic rail joiners

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Posted by richhotrain on Wednesday, July 23, 2014 5:58 PM

Since the gaps seem appropriately placed and the wiring appears correct, that makes the AR-1 suspect.

Is it new?

You could create a short reversing section, perhaps using the South Main Bypass section of track.

Just run a loco through a temporary reversing section to verify that the AR-1 is working properly.

Rich

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Posted by richhotrain on Wednesday, July 23, 2014 5:53 PM

Could be a defective AR-1.

How did you make your rail gaps?

Rich

 

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Posted by trafficdesign on Wednesday, July 23, 2014 5:46 PM

richhotrain

The wiring looks to be correct.

Have you tried adjusting the TTC (Tunable Trip  Current)?

Turn the plastic screw counter clockwise all the way till it stops.  That is the 0.25 amps setting.  Run a train through.  If it shorts, turn the TTC screw clockwise 1/4 turn and run the train again.  Keep doing this till the short ceases to occur or until you cannot turn the TTC screw any further.  That is the 8.0 amp setting.

Rich

Yup. It makes no difference. Still get a hard short and the AR1 won't trip. Always possible that my AR1 is defective. No idea what else to do or try....???

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