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Where's the short?

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Posted by gdelmoro on Sunday, July 23, 2017 10:28 AM

floridaflyer

Connecting the AR to a small piece of track won't tell you much, as the rails are not connected is any way. Bypass the AR and see if there is a short in the reversing section. You could also temporarily hook up the other reversing section using the AR and see if that shorts. moving the location of the gaps shouldn't affect the shorting problem unless in doing so the problem section of track,( if there is a problem section of track) is removed from the reversing section. 

 

I can run some temporary wires to the other section and see what happens.

Gary

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Posted by richhotrain on Sunday, July 23, 2017 11:04 AM

floridaflyer

Connecting the AR to a small piece of track may indicate the AR is fine.  Bypass the AR and see if there is a short in the reversing section. You could also temporarily hook up the other reversing section using the AR and see if that shorts. If no short then the track and wiring in the problem section is suspect, if it shorts the AR or the wiring leading to the AR is suspect.  Moving the location of the gaps shouldn't affect the shorting problem unless in doing so the problem section of track,( if there is a problem section of track) is removed from the reversing section. The cause can only be AR, wiring, track, or a combination of some of the first three. Proving the AR reliable, or not, is in my view the first step. 

 

I don't think that hooking up the AR with the output to a piece of track proves anything. If you gap a section of track on your layout in order to isolate that section of track, then wire the input side of the AR to the main bus and a set of feeders from the output side to the reversing section, the AR is working if it flips the polarities inside the reversing section as the loco enters or exits the reversing section. We are just making things way to complicated here.

Rich

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Posted by rrinker on Sunday, July 23, 2017 11:04 AM

 If it shorts oout as soon as the wires are hooked up, then you definitely have a failed gap or a feeder hooked up on the opposite side of the gap somewhere. Witht he Frog Juicer not connected, try measuring voltage across the gaps, and also diagonally across the gaps (right rail on one side of gap to left rail oon oopposite side of gap, and vice-versa). With the gaps in place and no power feeders to the reverse section, you should not get any reading no matter where you measure across the gaps. The reverse section should be completely dead. If not - you've found the problem.

                             --Randy

 


Modeling the Reading Railroad in the 1950's

 

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Posted by floridaflyer on Sunday, July 23, 2017 11:07 AM

Gary, I edited my post while you were responding. Will be interested to see if the other reversing section shorts or not.  

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Posted by gdelmoro on Sunday, July 23, 2017 11:11 AM

rrinker

 If it shorts oout as soon as the wires are hooked up, then you definitely have a failed gap or a feeder hooked up on the opposite side of the gap somewhere. Witht he Frog Juicer not connected, try measuring voltage across the gaps, and also diagonally across the gaps (right rail on one side of gap to left rail oon oopposite side of gap, and vice-versa). With the gaps in place and no power feeders to the reverse section, you should not get any reading no matter where you measure across the gaps. The reverse section should be completely dead. If not - you've found the problem.

                             --Randy

 

 

Will do

Gary

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Posted by mikeGTW on Sunday, July 23, 2017 11:45 AM
Randy this is just a guess and maybe you can say yes or no but could that switch at the bottom have something to do with the short ? He said he ran wires to three different sections of the reverse loop
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Posted by richhotrain on Sunday, July 23, 2017 11:51 AM

mikeGTW
Randy this is just a guess and maybe you can say yes or no but could that switch at the bottom have something to do with the short ? He said he ran wires to three different sections of the reverse loop
 

Mike, while we are waiting to hear from Gary, I would say that your guess is as good as anybody's. Depending upon what Gary comes up with, I think we need to start off with a clean drawing of where those gaps are and how and where the feeders are wired. That reversing section on the right side is as simple as a reversing section can be.

Rich

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Posted by mikeGTW on Sunday, July 23, 2017 12:23 PM

Rich  totally agree   if he goes from the top sw  original gap to the point side of the bottom sw   simply as can be    But he had 4 sets of gaps, a switch and three sets of fedeers from the reversing unit   thats just looking for trouble

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Posted by richhotrain on Sunday, July 23, 2017 12:29 PM

It would also be interesting to have some measurements.

How long is that diagonal stretch of track?

How long is that entire loop of track on the outside right?

Just curious how much reversing section he has to work with and how many or how few feeders are actually required for efficient operation.

Rich

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Posted by gdelmoro on Sunday, July 23, 2017 12:45 PM

richhotrain

It would also be interesting to have some measurements.

How long is that diagonal stretch of track?

How long is that entire loop of track on the outside right?

Just curious how much reversing section he has to work with and how many or how few feeders are actually required for efficient operation.

Rich

 

Diagnal 4' to switch, loop about 11'.

 

PROBLEM SOLVED!

In 500 years you could (or at least I could) NEVER guess what the problem was.

1st I connected to the other loop. ALL fine.

Then - By accident I turned on the power for the layout lights instead of the DCC system and the loco sitting on the reverse loop comes on! Confused. I got it, the layout is haunted and there is nothing I can do Angel.

Probably Rich and Randy remember this was a DC Layout. At that time I used telephone wire to power the Blocks. This being a reverse loop it too had telephone wire. I "thought" I ripped it all out only leaving the telephone wire connected to lighting.

Inside a tunnel adjacent to a passenger station (lighted) was a set of track feeders which I thought were light wires and connected them to the 12VDC power supply. I guess enough of a short to trip the EB1 Even without the 12V power on.

THANKS for all the help and improvements to the track plan.

Gary

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Posted by BigDaddy on Sunday, July 23, 2017 2:02 PM

Randy nailed it on his first post

rrinker
that's your reversing section, and should be powered only from the output of the Frog Juicer.

I tried to clarify that with my question to Randy, but the placement of the gaps, the other reversing loop, the use of a frog juicer were giant red herrings  suckered everyone in. 

I could have phrased it better, but I was up all night with a sick dog.  If the juicer was set up correctly and if the gaps existed as described (no matter how many extra) there should have been two electrically isolated pieces of track, the mainline and the reversing loop; when he connected the wire and the EB1 shorted.

That could only happen if:

BigDaddy
unless there is some other data we need to know about.

well well

Robert;

Imagine 2 parallel tracks, from bottom to top on your screen.   At the top they both go through a tunnel.  The right track has a right hand turn out that leads to a track that goes up, around horseshoe curve, does a 180 and joins the left track via left hand turn out (as you look at the tunnel) 

You have engine A on the left track and engines B & C on the right

A  B

    C

A&B  go down the main and through the tunnel, C takes the right turnout, does the 180 and now it's connects to the left track headed down the screen in an opposite direction as Loco A  While it started on a different track, it has returned on a different track, in a reverse orientation from the usual traffic.

Henry

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Posted by richhotrain on Sunday, July 23, 2017 2:46 PM

Henry, I cannot imagine how we could get on without you.  Laugh

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Posted by BigDaddy on Sunday, July 23, 2017 3:07 PM

richhotrain

Henry, I cannot imagine how we could get on without you.  Laugh

Another 2 years of studying under you and Randy and I might be able to explain the conflict between a circuit breaker and a reverser.

Henry

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Posted by floridaflyer on Sunday, July 23, 2017 3:30 PM

[quote user="richhotrain"]

 

 
floridaflyer

Connecting the AR to a small piece of track may indicate the AR is fine.  Bypass the AR and see if there is a short in the reversing section. You could also temporarily hook up the other reversing section using the AR and see if that shorts. If no short then the track and wiring in the problem section is suspect, if it shorts the AR or the wiring leading to the AR is suspect.  Moving the location of the gaps shouldn't affect the shorting problem unless in doing so the problem section of track,( if there is a problem section of track) is removed from the reversing section. The cause can only be AR, wiring, track, or a combination of some of the first three. Proving the AR reliable, or not, is in my view the first step. 

 

 

 

I don't think that hooking up the AR with the output to a piece of track proves anything. If you gap a section of track on your layout in order to isolate that section of track, then wire the input side of the AR to the main bus and a set of feeders from the output side to the reversing section, the AR is working if it flips the polarities inside the reversing section as the loco enters or exits the reversing section. We are just making things way to complicated here.

 

Rich

 

Actually Rich I think when OP  hooked up the the small piece of track and it didn't short it showed that the AR could be hooked up to a isolated piece of track and not short and if the AR were hooked up to the reverse section on the layout and it shorted the problem was with the reverse section. I was slow to realize that. 

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Posted by richhotrain on Sunday, July 23, 2017 3:43 PM

floridaflyer
 

Actually Rich I think when OP  hooked up the the small piece of track and it didn't short it showed that the AR could be hooked up to a isolated piece of track and not short and if the AR were hooked up to the reverse section on the layout and it shorted the problem was with the reverse section. I was slow to realize that. 

 

Yeah, I guess so. At first, probably because I read Gary's initial post too quickly, I thought that he was using a frog juicer to power the frog and failed to realize that he was using it as an auto-reverser. Once I realized that he was using it as an auto-reverser, I took for granted that the Tam Valley Frog Juicer was likely not defective, so I began to look closer at the placement of the gaps and inquired about the placement and number of feeders.

What often happens in this kind of thread, and this is not a criticism of Gary, is that we tend to presume that the feeders are wired correctly and obviously we shouldn't. From Gary's drawings, we could critique the placement of the gaps, but the feeders are a whole different question.

Anyhow, kudos to Gary who, with Randy's help and that of others, solved his own problem. 

Rich

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Posted by gdelmoro on Sunday, July 23, 2017 6:12 PM

The reason I figured it out was Dumb Luck! If I hadn't flipped the layout lights on by accident chances are I would find those old feeders when I got frustrated enough to rip out the section of track and re-do it.  This piece is part of the 1/3 left from the old layout.

every time I have a problem Rich, Randy and others join in to try and solve it and so far ..... thanks to you guys we're batting 1000.

Also, Rich if you asked about feeders I would have sworn they were connected correctly. They were, except that there were also additional ones causing the short. 

One day I may be able to help someone like you guys Bow

Those old feeders were about 4 inches inside this tunnel.

Gary

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Posted by ROBERT PETRICK on Tuesday, July 25, 2017 8:44 AM

I hesitate to revive this thread . . .

During the discussion the other day I did not have access to my AutoCAD computer. I asked if somebody could re-paint the two yellow mainlines on Gary's layout as separate colors. Nobody did. Here's a sketch:

 

I left off the red ferry yard, the green ladder yard, and the yellow passing siding because they have no bearing on the problem.

Two questions: 1) Does anyone understand why I requested the two yellow mainlines be re-painted? and 2) Does anyone understand the significance?

This is not a joke, and I am not trying to start an argument. These are serious questions.

Robert

 

 

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Posted by BigDaddy on Tuesday, July 25, 2017 9:56 AM

I know but I'm not going to give it away.  I replied to your pm earlier.  For some reason I cannot log on with my laptop today.

Henry

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Posted by richhotrain on Tuesday, July 25, 2017 10:27 AM

ROBERT PETRICK

Two questions: 1) Does anyone understand why I requested the two yellow mainlines be re-painted? and 2) Does anyone understand the significance?

This is not a joke, and I am not trying to start an argument. These are serious questions.

Robert 

Robert, with all due respect, what are you talking about? Confused

Rich

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Posted by gdelmoro on Tuesday, July 25, 2017 2:51 PM

ROBERT PETRICK

I hesitate to revive this thread . . .

During the discussion the other day I did not have access to my AutoCAD computer. I asked if somebody could re-paint the two yellow mainlines on Gary's layout as separate colors. Nobody did. Here's a sketch:

 

I left off the red ferry yard, the green ladder yard, and the yellow passing siding because they have no bearing on the problem.

Two questions: 1) Does anyone understand why I requested the two yellow mainlines be re-painted? and 2) Does anyone understand the significance?

This is not a joke, and I am not trying to start an argument. These are serious questions.

Robert

 

 

 

I give up 

Gary

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Posted by ROBERT PETRICK on Wednesday, July 26, 2017 7:19 AM

richhotrain

 

 
ROBERT PETRICK

Two questions: 1) Does anyone understand why I requested the two yellow mainlines be re-painted? and 2) Does anyone understand the significance?

This is not a joke, and I am not trying to start an argument. These are serious questions.

Robert 

 

 

Robert, with all due respect, what are you talking about? Confused

Rich

Apparently the answer to Question 1 is no, and the answer to Question 2 is also no.

There are no reversing sections on this layout, there is no need to wire it as if there were, there is no need to cut isolation gaps in any rail, and there is no need for any auto-reversers.

The two mainlines form independent closed loops. They are completely isolated from each other despite being parallel and in such close proximity for their entire length. And those blue lines everyone keeps calling reversing sections are not reversing sections. They are crossovers that move traffic from one loop to the other and back again. If wired correctly, there would be no conflicts regarding polarity.

I'm sorry for pointing this out.

Robert 

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Posted by DSchmitt on Wednesday, July 26, 2017 7:59 AM

Deleted

I tried to sell my two cents worth, but no one would give me a plug nickel for it.

I don't have a leg to stand on.

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Posted by BigDaddy on Wednesday, July 26, 2017 8:36 AM

I still need convincing. 

I believe if you put 3 engines, one at each track, at point B, all facing right and run them around the track to point C.  Two of them will be facing nose to nose.  Do the same thing at point A with the engines facing left.  Run them to point D and two of them will be nose to nose. 

Paint all the engines red on the left and black on the right.  That represents the how the track is wired. When you get to points C & D in my examples, you are in conflict.

Changing the subject, the smaller font text I had saved in wordpad and copied it to this post.  How do I make it the same size as other text?  Format makes bolder bigger or smaller but not normal.

Henry

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Posted by floridaflyer on Wednesday, July 26, 2017 9:06 AM

I believe that if you run the three engines starting a point A and run them left, using one DC power pack, the locos on the blue and orange will go left and the one on the yellow will go right, turn the loco on the yellow so it is facing forward and and when they arrive at points C or D they will all be facing the same direction.  I agree with Robert there is no reversing section. The second diagram threw a monkey wrench into things.

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Posted by ROBERT PETRICK on Wednesday, July 26, 2017 9:29 AM

BigDaddy

I still need convincing. 

I believe if you put 3 engines, one at each track, at point B, all facing right and run them around the track to point C.  Two of them will be facing nose to nose.  Do the same thing at point A with the engines facing left.  Run them to point D and two of them will be nose to nose. 

Paint all the engines red on the left and black on the right.  That represents the how the track is wired. When you get to points C & D in my examples, you are in conflict.

Changing the subject, the smaller font text I had saved in wordpad and copied it to this post.  How do I make it the same size as other text?  Format makes bolder bigger or smaller but not normal.

 

Hey Henry-

Your point about placing three engines at Point B is correct. The one that causes the nose-to-nose conflict will always be the one placed on the yellow main. There is, however, one passing siding (shown on the original sketch, but not here) that might allow a daring Casey Jones saw-by maneuver to resolve that conflict, but it would need to be timed very carefully.

Because of the geometric arrangement of the layout, traffic on the yellow main and the orange main will always run in opposite directions to the other, and placing that third engine at Point B facing the same as the other two will cause a conflict. That is the thing that makes this layout actually pretty clever and perfect to operate in a DC environment: it makes trains appear as if they are reversed without actually doing so; crossing over to the other main accomplishes that. Trains should always move in one direction (that is, clockwise on one mainline loop and counter-clockwise on the other). And if the 0-5-0 places a train differently, that nose-to-nose conflict will occur within a minute. But what you described is not a reversing operation; it is a placement of trains.

You mentioned (in a PM) about painting cars red/black. I understood what you meant. Using your above example . . . Instead of three cars, use only one. Run over the entire layout along every course you can imagine. You will see. Plus, you will see that you can never get the thing turned around. I made a sketch showing the actual red/black rails and it shows this. Once again, I am physically separated from my AutoCAD computer. Later on, I will get that sketch and send it along.

In the meanwhile, you can do another experiment if you don't mind. Take a bare naked track plan and place red/black indicators as follows: 1) start with one mainline and assign red/black tags in any orientation, 2) mark both blue crossovers to match the first main, 3) then mark the other main to match both the crossovers. The orientation of the tags for second main will be opposite those of the first. This is not a problem, electrically. Do not mark both mains in sequence together at first. They are not related and are not compatible. That is where Gary made a (perfectly honest) mistake. There will be no conflicts.

Robert

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Posted by BigDaddy on Wednesday, July 26, 2017 10:36 AM

Rough crowd this morning.  

You changed the rules on me.  Crying  DC ? It was always a DCC layout.  However I did not appreciate the cleverness of it, until you mentioned it. 

If it were my layout I would have an internal crossovers or two between the main lines, but it's not my railroad and that would be changing the rules too.

Honest question, do people wire dual mainlines in opposite orientation?  One might be in my future, but my old layout did not have a dual line.  I suspect they don't because if the wanted the same cross overs that I would, they would have reversing loops.  For me there would be an inevitable feeder left-right mixup.

We were given the wiring red/black orientation in Gary's 1st pic.  I didn't know we were allowed to change that but I agree Robert with the wiring he suggests, Gary could do without reversers.  Gary it sounds like you have some work to do. Wink

Gary that top left green switchback siding in your 1st pic is a S curve and it will be real hard to work, S curve or not.

 

 

Henry

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Posted by floridaflyer on Wednesday, July 26, 2017 10:49 AM

Big Daddy, I only used DC to clearly show the lack of reversing section. If DCC were used  it could mask the fact that the loco on the yellow track was indeed moving in the same direction as the other two locos.

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Posted by DSchmitt on Wednesday, July 26, 2017 10:55 AM

 Dtrak2 by Donald Schmitt, on Flickr

 Dtrak1 by Donald Schmitt, on Flickr

I tried to sell my two cents worth, but no one would give me a plug nickel for it.

I don't have a leg to stand on.

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Posted by gdelmoro on Wednesday, July 26, 2017 11:38 AM

ROBERT PETRICK

 

 
richhotrain

 

 
ROBERT PETRICK

Two questions: 1) Does anyone understand why I requested the two yellow mainlines be re-painted? and 2) Does anyone understand the significance?

This is not a joke, and I am not trying to start an argument. These are serious questions.

Robert 

 

 

Robert, with all due respect, what are you talking about? Confused

Rich

 

Apparently the answer to Question 1 is no, and the answer to Question 2 is also no.

There are no reversing sections on this layout, there is no need to wire it as if there were, there is no need to cut isolation gaps in any rail, and there is no need for any auto-reversers.

The two mainlines form independent closed loops. They are completely isolated from each other despite being parallel and in such close proximity for their entire length. And those blue lines everyone keeps calling reversing sections are not reversing sections. They are crossovers that move traffic from one loop to the other and back again. If wired correctly, there would be no conflicts regarding polarity.

I'm sorry for pointing this out.

Robert 

 

Robert I don't seem to understand, If you look at the wiring there is a short without an AR. Note that that each single line on the drawing represents 2 tracks with one wired to the Black bus wire and the other to the Red. Both mainlines are wired the same with the black and red wired on the same rails throughout the dogbone. Prior to the switch that leads to the center diagonal you can see that the top rails of each mainline connect to the black bus wire and the bottom to the red.  When you pass the switch they are reversed.

Coming around the loop off the top right and then up the diagonal from bottom to top there would be a short since the red feed and black feed would connect to each other.  

The same occurs with the bus connections off the main (top center) the track rails are wired the same as the main (Black on top rail Red on bottom) when it reconnects to the main they cross again with the black connecting to the red. another short.

What am I missing?

Gary

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Posted by DSchmitt on Wednesday, July 26, 2017 11:45 AM

Will be electrical short if wired + rail as shown. Reverse + & - on yellow and there will be no short.  If crossovers are installed  between red and yellow they will need insulated joiners between switches and "reverse loop" wiring will be required. 

 Dtrak3 by Donald Schmitt, on Flickr

I tried to sell my two cents worth, but no one would give me a plug nickel for it.

I don't have a leg to stand on.

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