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Does Auto Reverser Work in This Diagram?

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  • Member since
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  • From: Ontario Canada
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Posted by Mark R. on Wednesday, December 10, 2014 8:13 PM

Making the entire "Y" section the reverse, it could pose problems depending on how it it operated. Potentially, one train could be arriving from the top left into the station while another could be leaving the station towards the bottom. If the entire "Y" was the reversing section, the two trains could be crossing the gaps at the same time.

With the two tracks at the top isolated as per the diagram (each with their own reverser), trains could be entering and / or leaving from all points with no interference of the reversers having two trains in the block at the same time.

Mark.

¡ uʍop ǝpısdn sı ǝɹnʇɐuƃıs ʎɯ 'dlǝɥ

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Posted by richhotrain on Wednesday, December 10, 2014 5:28 PM

KisNap

I imagine I'd need 4 auto reversers, one for each rail going to/from the station.  

You do not need an auto reverser for each rail.  An auto reverser is used to match polarities between two sections of track.  So, in your case, you need 2 auto reversers, not 4.  

Any time that a section of track has the reverse polarity of an adjoining section, it is a "reversing section".  A reverse loop is just another reversing section.

A reverse loop presents a unique problem in that it not only requires an auto reverser, but it also has to be long enough to hold the entire train to prevent the loco from striking the trailing cars.

A passenger car or freight car with metal wheels, even without any lighting, can set off an auto reverser.  It has happened to me.  For that reason, the reversing section should be longer than your longest train. The only exception is that a car with plastic wheels will not set off an auto reverser.

I agree with Roger that you should consider making the tails of the wyes as your two reversing sections.  This would leave the entire upper section of track, and most of the mainline loop, as the non-reversing section.

Rich 

Alton Junction

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Posted by Mark R. on Wednesday, December 10, 2014 5:13 PM

The problem with the train being longer than the reversing section is that a powered engine may be crossing one end, and a lighted (powered) passenger car may still be crossing the gap at the other end causing the auto reverser to try and align the power to BOTH ends - which it can't do, and thus a short would occur.

If, under no circumstances, engines or cars that would be picking up power from the rails should NOT be bridging the gaps at both ends at the same time. If the cars in your train do not reply on rail power pick-up, then you would have no problems.

Mark.

¡ uʍop ǝpısdn sı ǝɹnʇɐuƃıs ʎɯ 'dlǝɥ

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  • From: Mount Vernon WA
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Posted by skagitrailbird on Wednesday, December 10, 2014 4:02 PM

Here is the part of the article pertaining to wyes to which I referred earlier.

Other Wye Configurations:

Here are some sample wye configurations. There is nothing magic about them. I am providing these to give you some ideas. A reason to use a particular one is to minimize the need to trigger the reversing circuit. Some systems hesitate briefly while the switching takes place.


" B"


" C"


" D"


" E"

 

I have shown these wyes drawn with a straight side. I only did that because it was easy to draw. Please realize the orientation of the wye can be any way you need it to be. In fact, look at "B" and "D" carefully. Turn "D" on its side. "D" and "B" are essentially the same!

Remember the basic rule of reversing sections: the reversing section must be at least as long as your longest powered train. Configuration "C" appears that it may be hard to implement if you have a lighted passenger train. It could also be a problem if you have a lighted caboose. If the only powered unit is your locomotives, than the reversing section in "C" may be able to be short. If you are lashing up locomotives, be sure it is at least as long as your longest lashup.

My reading of this would say if your lighted cars have plastic wheels it may not matter. I emphasize may because it depends upon how your car lights are powered. If by batteries then I do not believe the "excess" length matters. But if by some sort of wiper getting power from the track I think it does matter.

PS: You may have to copy the article segment and pasteit into a word processing application to be able to see all of it.

Roger Johnson
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Posted by KisNap on Wednesday, December 10, 2014 3:50 PM

I've actually looked at that site already and while it was helpful, I didn't know what difference there may be since it's not a reversing loop.  The diagram is to scale (1 square is 1 square feet), but I was hoping to expand the station tracks an extra foot.  What would happen with the train being longer than the isolated track when there are lighted cars?  I'm more interested in why it would happen so I can get a better understanding of the problem.

I'm assuming that if the wheels are plastic that the length of the train is irrelevant.  Is that correct?

The N scale section of my website is now uploaded with a lot of various things.  Check it out: www.CarlettaTrains.com

  • Member since
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Posted by skagitrailbird on Wednesday, December 10, 2014 3:36 PM

I agree with Mark. Two auto reversers should do the trick. But if I understand your initial post, the gridwork in the diagram may not be to scale since you indicated your lighted trains will be longer than your drawn reversing section. That would be a problem.

How far do the Y's tail tracks (those going off the bottom of your drawing) go? Far enough for your longest lighted train? If so, I would make the Y your reversing section, removing all of the gaps on the two horizontal main lines and on the tail tracks near the lower turnouts and adding gaps to the two Y tracks at the left hand turnouts. One auto reverser on each of the two Y tracks should then do the trick.

You might want to take a look at this link: http://www.wiringfordcc.com/track_2.htm#a19

About half way through the article there is a section dealing with wiring reversing sections.

Roger Johnson
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  • From: Ontario Canada
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Posted by Mark R. on Wednesday, December 10, 2014 3:19 PM

You can eliminate the two isolated sections on the lower right two tracks and just leave the two tracks across the top isolated and install an auto reverser on each of the two tracks.

Based on your grid work, any train that will fit within the station tracks would fully fit within either of the two upper tracks to which the auto-reversers are connected .... very important, especially if you are running lighted cars.

Mark.

¡ uʍop ǝpısdn sı ǝɹnʇɐuƃıs ʎɯ 'dlǝɥ

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Posted by KisNap on Wednesday, December 10, 2014 2:47 PM

Sorry for the lack of information. 

1) The station is the green rectangle in the upper right hand corner. 

2) Eack line represents 1 line of track so there are a total of 4 tracks leading to wards the switching area that then goes to the station.

3) The two paralell tracks on the left hand side that go to the left and lower edges of the picture are the main lines.

The N scale section of my website is now uploaded with a lot of various things.  Check it out: www.CarlettaTrains.com

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  • From: Mount Vernon WA
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Posted by skagitrailbird on Wednesday, December 10, 2014 2:27 PM

Some of questions:

  1. Where will the station be located?
  2. Does each brown line represent one rail or a track (two rails)?
  3. Which brown lines represent the main line(s)?

I don't guarantee I can come up with the answer to your question but this info should help.

Roger Johnson
  • Member since
    August 2014
  • 122 posts
Does Auto Reverser Work in This Diagram?
Posted by KisNap on Wednesday, December 10, 2014 2:12 PM

My next layout will have a station that allows trains to leave it going in either direction in the layout.  From everything I read, it seems necessary to have the auto reversing section larger than your largest train, but those were always geared towards loops.

In the diagram below, my trains will be longer than the reversing section which is illustrated by the green lines representing the isolation connectors.  The train will pass straight through, however the train will be entering the switching area as new cars are still coming in.  Some of my passenger cars are lighted which I heard could be an issue.

I imagine I'd need 4 auto reversers, one for each rail going to/from the station.  The switching area and station rails would then be powered in the same polarity as the main line.  If this setup won't work, are their any suggestions as to modifications of where to isolate the tracks?

I thought of isolating everything up until the station and having the whole switching area reverse, but then I figured that would mess up other trains who are traveling through the switching area at the same time.

Any advice is very welcome!  Thank you!!!

The N scale section of my website is now uploaded with a lot of various things.  Check it out: www.CarlettaTrains.com

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