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Double track reversing loop

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Double track reversing loop
Posted by Allegheny2-6-6-6 on Wednesday, October 21, 2009 11:49 PM

 I am in the process of adding a double track mainline to the new layout for simplicity sake picture two large ovals if I have a train running on lets say the out side track and want to switch it over to the inside track as long as the train is going in the same direction no problem  but what if I have the two trains running in opposite directions and switch from one track to the the other I presume I will need an auto reverse module but will I need one for each line will one unit work both tracks?

Just my 2 cents worth, I spent the rest on trains. If you choked a Smurf what color would he turn?
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Posted by locoworks on Thursday, October 22, 2009 2:50 AM

you don't need an auto reverser for going between loops on DCC, the track polarity doesn't change, just the instructions to the train. 

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Posted by richhotrain on Thursday, October 22, 2009 4:53 AM

Allegheny2-6-6-6

 I am in the process of adding a double track mainline to the new layout for simplicity sake picture two large ovals if I have a train running on lets say the out side track and want to switch it over to the inside track as long as the train is going in the same direction no problem  but what if I have the two trains running in opposite directions and switch from one track to the the other I presume I will need an auto reverse module but will I need one for each line will one unit work both tracks?

Allegheny,

locoworks is correct.  There is no need for an auto reverse unit in your situation.

Get yourself a couple of colored lead pencils and draw a simple diagram, using a different color for each rail.  That will confirm the correct polarity and help you visualize polarity.

Rich

Alton Junction

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Posted by Hankenstein on Friday, June 3, 2022 7:33 PM

I am not so certain he payed attention to your question as I have the same situation, inner circle (not reall a circle, but it makes it easier to picture) and an outer circle. outer circle wired red on rail A and black on rail B inner circle exact opposite so that they run in OPPOSITE directions, hence they ARE reversed polarity 23' x 12'  trains will switch tracke on either side of the long run at relatively the same time I too am wondering about the number of auto reversers I hope someone can help us

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Posted by jjdamnit on Wednesday, June 8, 2022 4:38 PM

Hello All,

Allegheny2-6-6-6
...what if I have the two trains running in opposite directions and switch from one track to the the other(?)

It will look something like this...Gomez Addams train wrecks minus the explosives.

locoworks
(Y)ou don't need an auto reverser for going between loops on DCC, the track polarity doesn't change, just the instructions to the train.

Hope this helps.

 

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

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Posted by York1 on Wednesday, June 8, 2022 4:57 PM

Is there a reason the inner and outer loops are wired oppositely?

York1 John       

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Posted by dehusman on Wednesday, June 8, 2022 5:29 PM

Hankenstein
I am not so certain he payed attention to your question as I have the same situation, inner circle (not reall a circle, but it makes it easier to picture) and an outer circle. outer circle wired red on rail A and black on rail B inner circle exact opposite so that they run in OPPOSITE directions,

Why would you do that and intentionally cause yourself problems?

What reason is there to wire the loops like that?

There are conventional block control options but they really don't work with that wiring.

I too am wondering about the number of auto reversers I hope someone can help us

Auto reversers are generally only work in DCC.  If you have DCC, therey is ZERO need to wire the loops differently.

Dave H. Painted side goes up. My website : wnbranch.com

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Posted by jjdamnit on Wednesday, June 8, 2022 5:53 PM

Hello All,

All kidding aside, I presumed they are using DCC.

What system the OP is using; DCC or DC, is a vital question.

Knowing which system they are using will determine which solution- -if any- -is needed for their particular situation.

Hope this helps.

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

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Posted by CharlieM on Wednesday, June 8, 2022 7:45 PM

Agreed. If DCC no reversers needed. Running same or opposite directions, no problem. I had a layout with 3 concentric loops and still no reversers with DCC.

If DC I assume it would require 2 blocks for one crossover or 4 blocks for 2 crossovers. Thank goodness for DCC.

Charlie - Northern Colorado

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Posted by John-NYBW on Wednesday, June 8, 2022 10:34 PM

York1

Is there a reason the inner and outer loops are wired oppositely?

 

I wondered the same thing. It might make sense in a DC layout if you wanted the two ovals to run in the opposite direction and you never planned to have the trains switch but in DCC, why wouldn't you wire both tracks with the same polarity. In DC the track determines direction. In DCC the loco determines direction. 

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Posted by hjQi on Thursday, June 23, 2022 10:35 PM

I think you do need an auto reverse. You can imagine that your train first goes to the inner loop then it goes through another loop to change the direction. It is the changing direction loop needs the auto reverse.

Jerry

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Posted by floridaflyer on Sunday, June 26, 2022 3:46 PM

As others have mentioned, if the power is DCC the two loops should be wired the same not opposite, and no reverser is required as the decoder in the loco controls the direction. If the power is DC the auto reverser won't work.

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Posted by maxman on Monday, June 27, 2022 1:10 PM

Prior to Hankenstein's post, previous post was by richhotrain October 22, 2009.  I would presume that Allegheny2-6-6-6 has his issue corrected by now.

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Posted by richhotrain on Monday, June 27, 2022 4:04 PM

maxman

Prior to Hankenstein's post, previous post was by richhotrain October 22, 2009.  I would presume that Allegheny2-6-6-6 has his issue corrected by now.

 

As is so often the case.

Rich

Alton Junction

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