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Resolved - Bachmann Crossover Causing Short

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Resolved - Bachmann Crossover Causing Short
Posted by Ruckuss on Friday, October 7, 2022 10:07 AM

Hi everyone,

First, I'm relatively new to DCC and complex model layouts, but I'm not sure this is even a DCC issue.  My Digitrax Controller is detecting a short, even when no trains are running, so obviously I am creating a short in my Bachmann crossover that I don't understand

I'm building an HO scale layout, running all Backmann EZ Track and all digitrax components.   

For this discussion, assume that I have a continuous loop where the RR essentially does a 360 degree turnaround (no switches) at each end and has two tracks that run parallel between the two ends.  So, a continuous loop that sort of doubles back on itself.

I have attempted to install a Bachmann #6 Turnout into the section where the track runs parallel.

I fully understand that I will need to run power blocks in order to operate trains on this, although still learning exactly how to power the blocks.  I might be looking for help on that later.

For now, I'm trying to understand why I'm getting a short just by connecting this crossover, especially when both switches are in the open position.  This tells me there is something fundamental that I don't understand about this crossover switch and how I would need to provide power to it.

There appear to be gaps throught the rail sections that would prevent the different polarities from comming into contact with each other, regardless of the polarity on each track.  When I look at the back of the crossover, I do see copper that appears to span across the tracks (two of these at each end).

Two Questions:

1) If anyone could provide a basic understanding of why this is happening, I would appreicate it.  

2) How should I be providing power to this Switch?   Do the two tracks need the same polarity or reverse polarity? Or it doesn't matter because regardless, this switch requires an isolated power block (or multiple).  What is the correct way to install this so that a) it doesn't short and b) the two switches can be properly controlled through DCC?

Thanks

Mike

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Posted by hornblower on Monday, October 10, 2022 4:20 PM

Mike

A track plan would help us better understand and predict where potential shorts could occur.

Hornblower

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Posted by richhotrain on Monday, October 10, 2022 4:52 PM

Assuming that you wired the outer rail consistently all around the layout and the inner rail consistently all around the layout, everything should work fine if the crossover is set for the straight through route. (Or, should I say that most crossovers work that way. I don't own any Bachmann EZ track or crossovers, but there may be something different about the construction of the Bachmann crossover.)

However, if the crossover is set for the divergent route, there will be a point of opposite polarities in the center of the crossover, resulting in a dead short.

Why? Because you have created  a reversing section, or reverse loop if you like, and it must be isolated with proper gapping to prevent a short.

I do note that the frogs are "hot", that is wired for power to pass through. If that is the case, then the frogs need to be isolated and gapped.

If this is the problem, another solution would be to treat two end loops as reverse loops. To do this, the two end loops would be gapped and isolated from the parallel tracks in which case the crossover would become part of the non-reversing section and the crossover would not need to be gapped and isolated.

Rich

Alton Junction

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Posted by jjdamnit on Monday, October 10, 2022 7:25 PM

Hello All,

Ruckuss
...a continuous loop where the RR essentially does a 360 degree turnaround (no switches) at each end and has two tracks that run parallel between the two ends. So, a continuous loop that sort of doubles back on itself.

It sounds like the OP is describing a dogbone and is trying to install a #6 Bachmann Crossover Turnout. Bachmann offers these in a Left and Right versions.

The OP did not specify which one he is using.

They also offer these same units in a "DCC Version." 

Bachmann specifies that these are not to be used with DC control.

Since the OP has said he's using a Digitrax Controller (model not specified) this should not be a problem.

This is pure speculation on my part without a track plan.

If these crossover turnouts are non-power routing then installing them creates a reversing section.

richhotrain
...you have created a reversing section, or reverse loop if you like, and it must be isolated with proper gapping to prevent a short.

A DCC Auto Reversing unit will also need to be used to detect the shift in polarity when the locomotive(s) cross the gaps.

Hope this helps.

"Uhh...I didn’t know it was 'impossible' I just made it work...sorry"

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Posted by richhotrain on Tuesday, October 11, 2022 5:24 AM

Our OP, Ruckuss, posted three similar and somewhat related thread on Friday morning. We need to hear back from him, so we can further help. And a track plan would be most helpful so that we can visualize his track work.

Rich

Alton Junction

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Posted by NVSRR on Wednesday, October 12, 2022 11:05 AM

A track plan would be useful.   So would knowing if the turns outs are of the dc or dcc flavor.  
Shane

A pessimist sees a dark tunnel

An optimist sees the light at the end of the tunnel

A realist sees a frieght train

An engineer sees three idiots standing on the tracks stairing blankly in space

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Posted by Ruckuss on Thursday, November 24, 2022 9:32 AM

All. As a newbie to this forum i was unable to find my way back here yntil now

my problem was quite simple and it amazes me how hard it is to get a simple answer to the most basing questions 

the answer is this, which should have been on the damn instruction sheet, Both tracks should be wired the same in terms of wiring to the rails. If Black is on the right rail of the right track then Black needs to be on the right rail of the left track

Mike

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Posted by Ruckuss on Friday, November 25, 2022 8:43 AM

Thanks for the reaponse but my question/issue was much simpler than this

The simple answer is that both tracks have to have the rails wired the same. Regardless of anything else. If you power track A with Black on the right then you have to power track B with Black on the right. Thats all I needed to know. If the power is reversed it shorts

Mike

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Posted by richhotrain on Saturday, November 26, 2022 7:05 AM

Ruckuss

my problem was quite simple and it amazes me how hard it is to get a simple answer to the most basing questions 

the answer is this, which should have been on the damn instruction sheet, Both tracks should be wired the same in terms of wiring to the rails. If Black is on the right rail of the right track then Black needs to be on the right rail of the left track 

Ruckuss

Thanks for the reaponse but my question/issue was much simpler than this

The simple answer is that both tracks have to have the rails wired the same. Regardless of anything else. If you power track A with Black on the right then you have to power track B with Black on the right. Thats all I needed to know. If the power is reversed it shorts 

I, for one, answered your question/issue on October 10th. ConfusedConfused

Rich

Alton Junction

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Posted by Ruckuss on Saturday, November 26, 2022 8:54 AM

Thanks Rich. But to be honest, your answer wasnt and still isnt clear

I'm not trying to be an ass. Im trying to help others

i agree that depending on how I install this crossover, I may or may not create reversing loops and/or need for gaps. But take all of that away. If i just lay the crossover down and apply power to it with nothing else in the equation, all that stuff, like my layout, become irrelevant. 
The only thing remaining that IS relevant is how I apply power to the rails. Track A rail A is Black then Track B Rail A must be black.  That's it, and having that reversed was causing my issue. Once I knew that, the rest was just ensuring I maintained that consistency in my layout with necessary gaps and power blocks

i find your answers consistently helpful, but many others are noise. I find it very frustrating to have to read paragraphs of nonsense asking for my layout when the question has a yes or no answer. better yet, Yes, and here are the two things you need to know

Please know im responding in an effort to be helpful and I apologize for letting my frustration show

Mike

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Posted by richhotrain on Saturday, November 26, 2022 11:20 AM

Ruckuss

Thanks Rich. But to be honest, your answer wasnt and still isnt clear

I'm not trying to be an ass. Im trying to help others

i agree that depending on how I install this crossover, I may or may not create reversing loops and/or need for gaps. But take all of that away. If i just lay the crossover down and apply power to it with nothing else in the equation, all that stuff, like my layout, become irrelevant. 
The only thing remaining that IS relevant is how I apply power to the rails. Track A rail A is Black then Track B Rail A must be black.  That's it, and having that reversed was causing my issue. Once I knew that, the rest was just ensuring I maintained that consistency in my layout with necessary gaps and power blocks

i find your answers consistently helpful, but many others are noise. I find it very frustrating to have to read paragraphs of nonsense asking for my layout when the question has a yes or no answer. better yet, Yes, and here are the two things you need to know

Please know im responding in an effort to be helpful and I apologize for letting my frustration show 

For better or worse, you have to understand and accept how this forum operates. Some guys just want to be helpful so they respond even if their response proves worhtless. Some respond by speculating on a possible solution. Others actually offer specific advice that may or may not provide the solution to your issue. The reason that a lot of us ask for a track plan is to visualize the setup in question. We don't expect the entire track plan for a huge layout, but we often need to see enough to offer meaningful advice.

Anyhow, at this point, I don't know if you feel that you have your answer and/or whether you have tested the proposed solution on your layout. So, let me post the following graphic for your review.

The top diagram shows the wiring protocol with the outer rail in blue and the inner rail in red all around the double crossover. No short occurs on the straight through route, but a short will occur on the divergent route. Note that the colors of the rails mismatch on the double crossover, the point of opposite polarity.

The bottom diagram shows the wiring protocol with the double crossover and adjoining straight runs of track wired identically, blue rail on top, red rail below the blue rail. No short will occur either straight through or divergent. But the end loops wiring with not match the wiring of the double crossover or the adjoining straight runs of track. Note that the colors of the rails mismatch where the end loops rejoin the straight runs of track, points of opposite polarity. So, you need to treat the end loops as reversing sections, isolated by gaps and controlled by an auto-reverser in each loop.

Rich

 

Alton Junction

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Posted by Ruckuss on Saturday, November 26, 2022 12:05 PM

Thanks Rick. I got it. My problem is resolved 

Mike

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    September 2004
  • From: Dearborn Station
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Posted by richhotrain on Saturday, November 26, 2022 12:10 PM

Ruckuss

Thanks Rick. I got it. My problem is resolved 

YesYesYes

Rich

Alton Junction

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