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Help with Reversing Loops Please

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Posted by Anonymous on Thursday, July 24, 2014 1:30 PM

trafficdesign
 
BMMECNYC

Do you have a volt meter with a continuity checker?  If so turn off layout power, commince finding shorts.  Do you have any other feeders than the ones shown in the picture earlier? 

 

 

yep. I have a multimeter with a continuity setting but I've never used it before. I gather that it reads 1.0 and continuity would be a 0.0 which means that it is the same polarity.  If I get a 1.9 that is a short... Correct?

Problem is I am not sure where to test or what I am looking for??????

 

I dont know what brand of multi-meter you have, but the setting you need to use should say OL or 0 when there is no short and some number and possibly a beep when there is (test this by shorting the probes together).

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Posted by trafficdesign on Thursday, July 24, 2014 1:36 PM

richhotrain

I took some time this morning to prepare a diagram of the affected part of your layout, straightening out the right side loop. 

Wow Rich! I am very thankful for the amount of time that you and the rest of the forum is spending helping me. It is appreciated!!!!

richhotrain

Can you confirm that this is how you track wiring and gaps are set up?

Yes I believe so but I am going to go downstairs and stare at it one more time to confirm.... hang tight...

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Posted by richhotrain on Thursday, July 24, 2014 1:38 PM

Hey, no problem, I'm bored, our club is closed today for a private outing, so I can't play golf.   Laugh

Rich

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Posted by Anonymous on Thursday, July 24, 2014 1:40 PM

Re-install your AR-1 and double-triple check your wiring.

Then

start by checking across a set of rails on the same piece of track. 

Test the rails on the turnouts.  make sure you dont have a short between top and bottom rail of each track.  check all possible paths, note where shorts occur and the positions of turnouts when the shorts occur. 

If there are no shorts with track power off, you are looking of something with the locomotives shorting across adjacent rails (wide wheel tread will do it on PECO turnouts).  Some diesels have metal side frame trucks that overhang just enough to cause a short. 

With track power off, place your locomotive at the exact point the short occurs and note everything the wheels touch.  Lightly push the locomotive to one side or the other (side to side on the track), check that wheel treads are not touching opposite polarity rail. 

Check frogs of turnouts dead (no continuity with anything), on those turnouts that have metal frogs (if any).   

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Posted by trafficdesign on Thursday, July 24, 2014 1:51 PM

richhotrain

Can you confirm that this is how you track wiring and gaps are set up?

Rich

 

 

Confirmed. Wiring diagram is correct.

I am going to scrap this track and start over and go with the end loop option as I just can not troubleshoot this anymore. It is zapping my soul.

Is this what I should be shooting for if I want to make the entire inside of the end loop the reverse loop?????

Option B

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Posted by richhotrain on Thursday, July 24, 2014 1:55 PM

Before you do that, I have a suggestion.

Remove the gaps on the south main bypass and make sure that any feeders on the south main bypass are connected to the main bus, not the output side of the AR-1.  The south main bypass should not be part of the reversing section, as I have mentioned before.

Rich

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Posted by richhotrain on Thursday, July 24, 2014 2:05 PM

By the way, that recent diagram that you drew is not what Randy is suggesting.  He envisions two end loops that are gapped and isolated with no crossovers.  An AR-1 is placed inside each end loop to form a reverse loop.  Then the north and south mains, and the crossovers are wired in phase (i.e., red on top, blue on bottom, on both mains).

Rich

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Posted by trafficdesign on Thursday, July 24, 2014 2:06 PM

South Main Bypass was never a part of the reversing section and was never connected to the AR1. All power feeds to the south bypass come directly from the main bus and are wired red outside and black inside.

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Posted by richhotrain on Thursday, July 24, 2014 2:09 PM

trafficdesign

South Main Bypass was never a part of the reversing section and was never connected to the AR1. All power feeds to the south bypass come directly from the main bus and are wired red outside and black inside.

 

OK, I mentioned that because you show gaps on the south main bypass diagram and your photo appears to show feeders running from the south main bypass to the output side of the AR-1.

Any south main bypass gaps should be removed and any feeder wires from the south main bypass should be connected to the main bus.  

Have you done that?

Rich

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Posted by Anonymous on Thursday, July 24, 2014 2:14 PM

Is the locomotive completely off the turnout when the shorts occur?

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Posted by trafficdesign on Thursday, July 24, 2014 2:14 PM

richhotrain

By the way, that recent diagram that you drew is not what Randy is suggesting.  He envisions two end loops that are gapped and isolated with no crossovers.  An AR-1 is placed inside each end loop to form a reverse loop.  Then the north and south mains, and the crossovers are wired in phase (i.e., red on top, blue on bottom, on both mains).

Rich

 

Unfortunately, that would not work for me as the whole idea was to turn a train from the south main that was going to be exiting the north main and having it exit instead on the south main - in effect changing its direction of travel. Also the idea was to be able to stage trains so that I could choose to have them exit this section on either the north or south mains.

Another idea is to simply lock down the direction of travel eastbound (to the right) on the South Main and westbound (to the left) on the North Main and eliminate the hell of reverse loops from my life altogether

 

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Posted by richhotrain on Thursday, July 24, 2014 2:14 PM

If you are satisfied that the south main bypass is good, then here is the next step to get at the problem.

Disconnect the feeders to the south main from the AR-1.  Then run a train across the north main from left to right.

If it makes it through, turn it around by hand and run it back through the north main from right to left.

Does it successfully run through the north main reversing section in both directions?

Rich

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Posted by trafficdesign on Thursday, July 24, 2014 2:14 PM

Yes the loco is completely off the turnout when the short occurs.

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Posted by richhotrain on Thursday, July 24, 2014 2:16 PM

trafficdesign

 

 
richhotrain

By the way, that recent diagram that you drew is not what Randy is suggesting.  He envisions two end loops that are gapped and isolated with no crossovers.  An AR-1 is placed inside each end loop to form a reverse loop.  Then the north and south mains, and the crossovers are wired in phase (i.e., red on top, blue on bottom, on both mains).

Rich

 

 

 

Unfortunately, that would not work for me as the whole idea was to turn a train from the south main that was going to be exiting the north main and having it exit instead on the south main - in effect changing its direction of travel. Also the idea was to be able to stage trains so that I could choose to have them exit this section on either the north or south mains.

Another idea is to simply lock down the direction of travel eastbound (to the right) on the South Main and westbound (to the left) on the North Main and eliminate the hell of reverse loops from my life altogether

 

 

Well that is why we suggested the crossovers as the focal point of the reversing section in the first place.  

We are closing in on a solution.  Take heart.  Quit talking model railroad suicide.

Rich

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Posted by trafficdesign on Thursday, July 24, 2014 2:18 PM

richhotrain

 

Any south main bypass gaps should be removed and any feeder wires from the south main bypass should be connected to the main bus.  

Have you done that?

Rich

 

 
Isolated gaps still exist but shouldnt matter as the polarity of the track on both sides of the gap is the same and yes the South Main Bypass track is connected to the bus.
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Posted by richhotrain on Thursday, July 24, 2014 2:19 PM

OK, then follow my suggestion to disconnect the feeders from the south main to see if the train will run in both directions across the north main.

Rich

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Posted by Anonymous on Thursday, July 24, 2014 2:28 PM

trafficdesign
 
richhotrain

By the way, that recent diagram that you drew is not what Randy is suggesting.  He envisions two end loops that are gapped and isolated with no crossovers.  An AR-1 is placed inside each end loop to form a reverse loop.  Then the north and south mains, and the crossovers are wired in phase (i.e., red on top, blue on bottom, on both mains).

Rich

 

 

 

Unfortunately, that would not work for me as the whole idea was to turn a train from the south main that was going to be exiting the north main and having it exit instead on the south main - in effect changing its direction of travel. Also the idea was to be able to stage trains so that I could choose to have them exit this section on either the north or south mains.

Another idea is to simply lock down the direction of travel eastbound (to the right) on the South Main and westbound (to the left) on the North Main and eliminate the hell of reverse loops from my life altogether

 

 

 

You would still have the crossovers, but just the loops become the reversing section.  If you wire the track so that you have red/blue red/blue top to bottom the crossovers cease to be the point at which polarity switches.  The Loops are where the change occurs. 

Now that that is said I reccommend taking Rich's suggestion and disconnecting the south main electrically from the AR-1 and running a train on the north main as he previously suggested.  This will isolate the problem to a specific area. 

Troubleshooting can be soul crushing, but when you discover the problem it is very rewarding, and you learn something you didnt know before. 

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Posted by trafficdesign on Thursday, July 24, 2014 2:29 PM

richhotrain

OK, then follow my suggestion to disconnect the feeders from the south main to see if the train will run in both directions across the north main.

Hooking the AR1 back up to the layout. Am going to connect track power in and connect output feeders to North Main reverse section only.

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Posted by trafficdesign on Thursday, July 24, 2014 2:50 PM

Train runs in eastbound on the north main and exits westbound on the south main with no shorts.

Train enters south main eastbound and immediately shorts!

 

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Posted by richhotrain on Thursday, July 24, 2014 3:02 PM

OK, let's try to simplify this a little.  Let's talk numbers.  

A train will run eastbound on the north main across gaps #4 and continue on through gaps #3 without a short. Correct?

Then, when you turn it around, will it run westbound across gaps #3 and continue on through gaps #4 without a short?

For the moment, just run the loco and forget about the rest of the cars.

Rich

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Posted by Anonymous on Thursday, July 24, 2014 3:09 PM

Rich,

The North and South Main are still electrically connected through the crossvers. 

Andrew

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Posted by richhotrain on Thursday, July 24, 2014 3:15 PM

BMMECNYC

Rich,

The North and South Main are still electrically connected through the crossvers. 

Andrew

 

Yeah, I thought about that after I hit the Send button, but it doesn't matter for this first test.  What I was trying to accomplish was to have the OP remove any feeders on the south main in order to hone in on the north main wiring.  He says that the train moved east bound through the north main without a short.  So far, so good.  

But, then he says that a short immediately occurs when the train re-enters the south main, crossing gaps #2.  But, the AR-1 should react to the mismatch and flip polarities at that point.  Something doesn't add up here.

Rich

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Posted by trafficdesign on Thursday, July 24, 2014 3:18 PM

BMMECNYC

Rich,

The North and South Main are still electrically connected through the crossvers. 

Andrew

 

 correction:  I might have just found the issue and it is with a crossover that is not conducting power from the  north main to the left of the crossovers to the north main Section to the right of the crossover.... Let me diagram it and I will upload In half an hour.

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Posted by Anonymous on Thursday, July 24, 2014 3:24 PM

Rich,

Ive had that feeling since yesterday.  Something just does not add up.  Why is it shorting on only the one spot?

Andrew

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Posted by richhotrain on Thursday, July 24, 2014 3:28 PM

BMMECNYC

Rich,

Ive had that feeling since yesterday.  Something just does not add up.  Why is it shorting on only the one spot?

Andrew

 

Plus, I am not sure what he is referring to with that crossover.  We will have to wait to hear back from him.

Rich

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Posted by richhotrain on Thursday, July 24, 2014 3:35 PM

I wonder how much work it would be to temporarily remove the two crossovers so that each main is a straight through run.  If there is something wrong with one of the turnouts, it would help to remove the crossovers and just test the mains.

Rich

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Posted by trafficdesign on Thursday, July 24, 2014 3:36 PM

Top left crossover on north main when set to divergent route does not conduct power from the AR1 to the north main to the right of the crossover 

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Posted by richhotrain on Thursday, July 24, 2014 3:38 PM

Can you temporarily pull the two crossovers and put a section of main line track in place?

Rich

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Posted by richhotrain on Thursday, July 24, 2014 3:40 PM

Those turnouts better not be power routing or we are coming to hunt you down.  Super Angry

Rich

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Posted by Anonymous on Thursday, July 24, 2014 3:57 PM

Would you mind satisfying a curiosity of mine real quick?  Could you set your volt meter to 200 range AC volts and touch the leads to the track at the shorting location and tell me what voltage you get?  It should read either approximately 14.5V +0/-2 or 32V +1/-1, depending on how your voltmeter interperets the AC voltage, dont worry if it does read around 30V, thats just your voltmeter not understanding the DCC signal in the track.

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