Subscriber & Member Login

Login, or register today to interact in our online community, comment on articles, receive our newsletter, manage your account online and more!

"A MYSTERIOUS DCC PROBLEM "

2900 views
44 replies
1 rating 2 rating 3 rating 4 rating 5 rating
  • Member since
    December, 2005
  • From: west of Portland Oreg.( the city of Roses
  • 425 posts
"A MYSTERIOUS DCC PROBLEM "
Posted by TrainsRMe1 on Wednesday, August 09, 2017 6:39 PM

Hi All,

I'll just get to the point, this problem is just crazy!!! I have a short ""somewhere" in my wiring ,  I had to cross my bus wires (black to red, red to black)my bus wires are Red for the A Track, Black for the B track,  my feeders are the same,  I  have checked every single feeder, they all match up, as soon as I  match up the bus wires the short starts. (???????) Help!

  • Member since
    July, 2009
  • From: somerset, nj
  • 1,669 posts
Posted by gregc on Wednesday, August 09, 2017 7:22 PM

undo the last thing(s) you did just before the problem occurred.

when desperate, divide and conquer.  break bus and track in half and repeat on the half with the short

best of luck

greg - Philadelphia & Reading / Reading

  • Member since
    October, 2005
  • 729 posts
Posted by betamax on Wednesday, August 09, 2017 7:26 PM

Looks like you'll have to start disconnecting feeders until the short goes away. If you have a DMM with a continuity function you can just use the audible signal to tell when you find the culprit.

Check turnouts, as you might have a frog that is bridging A to B and needs to be isolated first.  Or you have a reverse loop that is bringing A to the B rail. Just do a visual inspection before you start cutting wires.  That way you might find a place to start disconnecting wires.

  • Member since
    December, 2005
  • From: west of Portland Oreg.( the city of Roses
  • 425 posts
Posted by TrainsRMe1 on Wednesday, August 09, 2017 7:47 PM

Well, I  do have a crossover just beyond where my short happened  in my bus wire. Hmmmmm

  • Member since
    July, 2006
  • From: Bradford, Ontario
  • 7,716 posts
Posted by hon30critter on Wednesday, August 09, 2017 9:56 PM

I suspect your crossover has created a reverse loop.

To find out, draw your track plan with both rails showing, one in red and one in black. If the red and black lines connect to each other at any point you have created a reverse loop which is causing your short.

Dave

  • Member since
    January, 2014
  • From: Cresskill, NJ USA
  • 656 posts
Posted by gdelmoro on Thursday, August 10, 2017 6:31 AM

Can you post a trak plan please?

Gary

  • Member since
    September, 2004
  • From: Dearborn Station
  • 16,677 posts
Posted by richhotrain on Thursday, August 10, 2017 11:44 AM

TrainsRMe1

I  have checked every single feeder, they all match up, as soon as I  match up the bus wires the short starts. 

What do you mean by "as soon as I match up the bus wires"?

If you are certain that every single feeder is wired correctly, then something else is shorting the system. Had you ever had the layout running without a short?

Rich

Alton Junction

  • Member since
    December, 2005
  • From: west of Portland Oreg.( the city of Roses
  • 425 posts
Posted by TrainsRMe1 on Thursday, August 10, 2017 1:12 PM

I'm at work now, but I  could do so tonight. 

  • Member since
    December, 2005
  • From: west of Portland Oreg.( the city of Roses
  • 425 posts
Posted by TrainsRMe1 on Thursday, August 10, 2017 1:14 PM

I had to mismatch my bus wire, which I should not have to Do, 

  • Member since
    January, 2009
  • 2,308 posts
Posted by RR_Mel on Thursday, August 10, 2017 1:23 PM

You need to post a simple block schematic of your wiring.  Simply reversing the wires on the DCC controller will not make any difference.  If you have other things hooked up to the controller disconnect them and see if that clears the short.
 
 
Mel
 
Modeling the early to mid 1950s SP in HO scale since 1951
 
My Model Railroad   
 
Bakersfield, California
 
I'm beginning to realize that aging is not for wimps.
  • Member since
    September, 2004
  • From: Dearborn Station
  • 16,677 posts
Posted by richhotrain on Thursday, August 10, 2017 1:48 PM

TrainsRMe1

I had to mismatch my bus wire, which I should not have to Do, 

 

If your bus wires are red and black, and your feeders are also red and black, and red is connected to red and black to black , you absolutely should not have a short.....................

.....................unless....................

...........you connected a red or black feeder to the wrong rail.

That's probably what you did, or someone else suggested, you created a reversing section.

Rich

Alton Junction

  • Member since
    January, 2014
  • From: Cresskill, NJ USA
  • 656 posts
Posted by gdelmoro on Thursday, August 10, 2017 2:44 PM

Well Rich, sometimes us DCC newbies can FIND ways to short things out.  

I had all my red feeders connected to red bus and black to black and had a short when I initially installed the system. Seems I had a red wire connected to what should have been a black rail and a black wire connected to what should have been a red rail Indifferent  I found it using the MR trick of taking an old freight car and painting ome side red and the other black and when I ran it arround suddenly THERE it was! i kept that little car on the tracks as i continued to wire both loops. Also how I confirmed where reverse loops were.

Gary

  • Member since
    September, 2004
  • From: Dearborn Station
  • 16,677 posts
Posted by richhotrain on Thursday, August 10, 2017 4:41 PM

gdelmoro

Well Rich, sometimes us DCC newbies can FIND ways to short things out.  

I had all my red feeders connected to red bus and black to black and had a short when I initially installed the system. Seems I had a red wire connected to what should have been a black rail and a black wire connected to what should have been a red rail 

Yep, that will do it.

Rich

Alton Junction

  • Member since
    December, 2015
  • 2,239 posts
Posted by BigDaddy on Thursday, August 10, 2017 7:28 PM

gdelmoro
Can you post a trak plan please?

Oh my! 

I used to think this was a good suggestion until every new pic of the track plan was a different track plan or it would change the orientation 180 degrees and then 90 degrees and upside down and backwards.   Be gentle with us. Smile

It still seems like a good idea to label tracks or turnouts so we don't have to refer to the turnout 1/3 of the way down on the left half of the pic.

 

Henry

COB Potomac & Northern

By the Chesapeake Bay

  • Member since
    December, 2005
  • From: west of Portland Oreg.( the city of Roses
  • 425 posts
Posted by TrainsRMe1 on Sunday, August 13, 2017 2:38 AM

Well, I wish I could post a trackplan, but I always have a problem in doing so, I did however used the old method of marking one of my old box cars one side red the other side black, I ran it all around my layout to( get this) only find that every single feeder matched the side of the box car!!! So I guess the only thing to do now is ( sigh) start all over, there must be a problem with the bus wire, I checked all of my turnouts, and none of them are causing the short, UUUGGGHHH!!

  • Member since
    September, 2004
  • From: Dearborn Station
  • 16,677 posts
Posted by richhotrain on Sunday, August 13, 2017 5:01 AM

TrainsRMe1

Well, I wish I could post a trackplan, but I always have a problem in doing so,

I did however used the old method of marking one of my old box cars one side red the other side black, I ran it all around my layout to( get this) only find that every single feeder matched the side of the box car!!!

So I guess the only thing to do now is ( sigh) start all over, there must be a problem with the bus wire, I checked all of my turnouts, and none of them are causing the short,

UUUGGGHHH!!

 

I don't see how the bus wires are causing a problem, especially if you only have a single set of bus wires. If, indeed, each and every feeder is matched to the correct bus wire, red to red, black to black, and no feeders are crossed from rail to bus, then the cause of the short is something else. It could be a reversing section or some other wiring snafu.

If I send you a PM with my email address, can you email me with a copy of your track plan so I can post it for you?

Rich

Alton Junction

  • Member since
    December, 2005
  • From: west of Portland Oreg.( the city of Roses
  • 425 posts
Posted by TrainsRMe1 on Sunday, August 13, 2017 8:25 AM

Sure, that would be great,  

  • Member since
    July, 2006
  • From: Sebring FL
  • 648 posts
Posted by floridaflyer on Sunday, August 13, 2017 8:35 AM

BigDaddy

 

 
gdelmoro
Can you post a trak plan please?

 

Oh my! 

I used to think this was a good suggestion until every new pic of the track plan was a different track plan or it would change the orientation 180 degrees and then 90 degrees and upside down and backwards.   Be gentle with us. Smile

It still seems like a good idea to label tracks or turnouts so we don't have to refer to the turnout 1/3 of the way down on the left half of the pic.

 

 Excellent point Henry
 
 
doug

  • Member since
    December, 2015
  • 2,239 posts
Posted by BigDaddy on Sunday, August 13, 2017 8:39 AM

TrainsRMe1
I had to cross my bus wires (black to red, red to black

Geographically wouldn't the problem be close to this point?  We haven't eliminated the frog issue either.  What turnouts are you using?

 

Henry

COB Potomac & Northern

By the Chesapeake Bay

  • Member since
    September, 2004
  • From: Dearborn Station
  • 16,677 posts
Posted by richhotrain on Sunday, August 13, 2017 9:52 AM

TrainsRMe1

Sure, that would be great,  

 

Done.  Check your PM.

Rich

Alton Junction

  • Member since
    January, 2014
  • 423 posts
Posted by ROBERT PETRICK on Sunday, August 13, 2017 10:12 AM

BigDaddy

Geographically wouldn't the problem be close to this point?  We haven't eliminated the frog issue either.  What turnouts are you using?

Yes, this could be the issue. Some turnouts (Peco Electrofrog) must be gapped on the downstream rails, even though no reversing section is involved.

Also Henry, I agree with your earlier comment about accurate, consistent track plans. Difficult enough to describe things in a forum even with perfect illustrations. Nearly impossible when the pictures don't match the words.

Robert 

LINK to SNSR Blog

  • Member since
    September, 2004
  • From: Dearborn Station
  • 16,677 posts
Posted by richhotrain on Sunday, August 13, 2017 10:19 AM

ROBERT PETRICK
 
BigDaddy

Geographically wouldn't the problem be close to this point?  We haven't eliminated the frog issue either.  What turnouts are you using? 

Yes, this could be the issue. Some turnouts (Peco Electrofrog) must be gapped on the downstream rails, even though no reversing section is involved.

Also Henry, I agree with your earlier comment about accurate, consistent track plans. Difficult enough to describe things in a forum even with perfect illustrations. Nearly impossible when the pictures don't match the words.

Robert  

Yeah, there's a lot we don't know here. Type of turnout? Overall track plan? New layout or modification to up and running layout? Did it all work good before?  Did it ever work well? Type of DCC system? Reversing sections?

Rich

Alton Junction

  • Member since
    September, 2004
  • From: Dearborn Station
  • 16,677 posts
Posted by richhotrain on Tuesday, August 15, 2017 5:38 AM

TrainsRMe1

Well, I wish I could post a trackplan, but I always have a problem in doing so,

Here is the track plan.

Rich

trainsrme.jpg

Alton Junction

  • Member since
    February, 2015
  • From: Ludington, MI
  • 228 posts
Posted by Water Level Route on Tuesday, August 15, 2017 5:54 AM

Is the "Klamath Falls Staging" connected to the "Hidden Stage Tracks", specifically where entered at the lower right hand corner of the track plan?

  • Member since
    September, 2004
  • From: Dearborn Station
  • 16,677 posts
Posted by richhotrain on Tuesday, August 15, 2017 6:06 AM

Water Level Route

Is the "Klamath Falls Staging" connected to the "Hidden Stage Tracks", specifically where entered at the lower right hand corner of the track plan?

 

No idea, that is all that the OP mailed me, but it is a good question.

The hidden staging could form a reverse loop, I suppose. On the posted track plan, I see no reverse loops or reversing sections.

Still wonder about the types of turnouts being used. Peco Electrofrogs?

New layout or modification to up and running layout? Did it all work good before?  Did it ever work well? Type of DCC system? 

Rich

Alton Junction

  • Member since
    February, 2002
  • From: Reading, PA
  • 23,094 posts
Posted by rrinker on Tuesday, August 15, 2017 7:18 AM

 If there are no return loops, then a short at a crossover has to be either an Electrofrog type turnout without proper gaps, or the two tracks being connected are not wired the same - ie if it is like this ||X|| then the bus should be ABXAB. If it's ABXBA then there will be a short even with Atlas turnouts.

EDIT: BTW, if it shorts on DCC, it would short on DC. It's not really a DCC problem, it's a track wiring problem.

 

                           --Randy

 


Modeling the Reading Railroad in the 1950's

 

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

  • Member since
    December, 2015
  • 2,239 posts
Posted by BigDaddy on Tuesday, August 15, 2017 8:29 AM

I saved the track plan and then blew it up.  The resolution does not improve.  lt says:

>Turnouts Atlas (manual)

The layout runs OK it could run better.  My DCC system is Digitrax Zepher  The Red Line is A rail the Black is B rail

There is a Peco turnout below the engine shop top right.

My eyes aren't good enough to follow the individual A & B rails to see where his bus "changes"  In some areas I can't say for sure how many tracks there are. 

There is either a crossing or a cross over in the peninsula that hangs down  at the right third of the diagram.  It is just at the end of the straight section.  I see other lines that could be cross overs above Coos Bay.

There are 3 paths to staging yards.  Are they yards or are they  loops?   Dunno. 

OP Aside from the shorting issue, what do you mean you wish it would run better?

Henry

COB Potomac & Northern

By the Chesapeake Bay

  • Member since
    December, 2005
  • From: west of Portland Oreg.( the city of Roses
  • 425 posts
Posted by TrainsRMe1 on Tuesday, August 15, 2017 10:31 AM

I just want it to run flawlessly, there is a crossover in Cushman, far right on the 2nd peninsula, as well as at the Umpqua River, along the wall on the far left, continuing from there coming through the town of Mapleton, to the 1st peninsula I have a Peco turnout handling my dbl main line to single track, that turnout is operated by a Tortoise, from there the single track runs through 3 tunnels, across McKenzie river, from there, I'm running a track to a lower level staging that is a reversal loop, I 'm using a Digitrax AR1 for the loop, meanwhile the mainline on the upper level runs to Eugene yard, engine shop to the left of the mainline, the South end of the yard, the mainline runs off into a hidden track that continues behind the scenery to the other side of the layout to Coos Bay Oregon. Now I  have noticed  there are two types of gauge wire for my bus, hmmm I  wonder if that could be the problem.???? 

Thanks Guys for the help, and thank you Rich for posting this for me.

 

  • Member since
    July, 2006
  • From: Sebring FL
  • 648 posts
Posted by floridaflyer on Tuesday, August 15, 2017 11:08 AM

You say the layout runs fine when the bus wires are reversed. Could it be that the reverse section is not isolated and when you reverse the buss you are in phase with the reverse section, when you return to black on black and red on red a short occurs, as you may not be in phase with the reverse section. This is just a guess on my part but it is odd that a short does not exist regardless of which way you have the buss wires.

  • Member since
    September, 2004
  • From: Dearborn Station
  • 16,677 posts
Posted by richhotrain on Tuesday, August 15, 2017 2:34 PM

Dunno, it seems that there is too much going on here to analyze this issue properly.

Is there a problem with the bus wires? Is there a problem with the feeders.  Is there a reversing section somewhere on the layout? Is there a necessary gap missing? Could it be a turnout? I just think there is too much going on .....in this thread.

Rich

Alton Junction

Subscriber & Member Login

Login, or register today to interact in our online community, comment on articles, receive our newsletter, manage your account online and more!
Popular on ModelRailroader.com
Model Railroader Newsletter See all
Sign up for our FREE e-newsletter and get model railroad news in your inbox!
ADVERTISEMENT
ADVERTISEMENT

Search the Community

ADVERTISEMENT
Find us on Facebook