# automatic switching question



## artgibson (Jan 2, 2008)

We need some help. Trying to set up track and siding so that a mining train
goes into tunnel empty and stops and second mining train loaded comes out
in same direction.
A siding has been set up for second train and we need info as to what needs to be done in order for it to work.
I have misplaced my LGB manual that had all that in fo in it.


----------



## toddalin (Jan 4, 2008)

I looked through the Bing Images and really didn't see the LGB set-up for the "leap-frog." I do this using electronics of my own design, and while I could describe how the LGB system does it, a picture is worth 1,000 words.

I know that someone on this forum has access to the proper LGB diagram. Hopefully, they will step forward.


----------



## chuck n (Jan 2, 2008)

If you have a loop it can be done with a passing siding, with a couple of diodes and gap tracks. One train can go clockwise and the other come out counterclockwise. Spring loaded switches will permit the transit of the trains in each direction, just by changing the polarity on the track. You can have the empty train enter the mine area, change the polarity and the loaded train will leave in the opposite direction. The next time around when the loaded train comes in a change in polarity will sent the empty out out the back and around to come in again, to complete the cycle.

We have done this many years with a Thomas train at a show every Christmas. Thomas goes around several times, and then stops in the siding and James goes out in the opposite direction with the change of polarity. 

Unfortunately, I'm on vacation and I don't have access to my diagrams.

It requires two diodes and four 1015U LGB gap tracks. Each siding has a diode across one of the gaps and one open gap. A little experimentation will provide the correct combination. 


This is all predicated in the assumption that you can use a loop.

Here is a picture of Thomas coming into the passing siding while James is waiting for a polarity change.











The switch James is facing is a spring switch. It will flop as James passes, returning for Thomas's next turn. Thomas has a spring switch at the end of his siding so that James will always go straight.

I think that something like this could be used for a mine. It would depend on your track plan and how much you want visitors to see.

The only problem I foresee is that the engine will be on different ends of the train, if you want to pretend that it is the same train.

Chuck


----------



## artgibson (Jan 2, 2008)

chuck n said:


> If you have a loop it can be done with a passing siding, with a couple of diodes and gap tracks. One train can go clockwise and the other come out counterclockwise. Spring loaded switches will permit the transit of the trains in each direction, just by changing the polarity on the track. You can have the empty train enter the mine area, change the polarity and the loaded train will leave in the opposite direction. The next time around when the loaded train comes in a change in polarity will sent the empty out out the back and around to come in again, to complete the cycle.
> 
> We have done this many years with a Thomas train at a show every Christmas. Thomas goes around several times, and then stops in the siding and James goes out in the opposite direction with the change of polarity.
> 
> ...


 I have misplaced my LGB diagram book. I like what I am hearing. Maybe I can look againn for my book. If any one has the diagram to share we would appreciate it.
Thanks for the quick response. We can use a loop with no problem and the back side of the loop is closed in.


----------



## chuck n (Jan 2, 2008)

Here is an outline of what I did. Unfortunately, I don't have a drawing program on my Laptop, so this is a word document. I put the gaps on the inside of one siding and the outside of the other. This permits a complete power circuit around the loop on both rails.


You will have to play with the orientation of the diodes. 





* Diode open gap*
* ____ ______________________________________________ ___
* * / _______________________________________________________ \ *
*S/ _/_______________________________________________________\ \S______*
*___/___ ______________________________________________ _____\________
**open gap *Diode 

S = Spring Switch


It has been years since I took the cover off my 1015Us to see the orientation of the diodes, but this should give you an idea of how to start.


Chuck

Sorry, I can't get the word formatting to copy correctly.

Lets see if this works.


----------



## toddalin (Jan 4, 2008)

*Everything You Wanted to Know*

I knew it existed on-line. Thanks to Kormsen's old post, you can find all of the LGB track and wiring diagrams at the link.

_Moderators, this should be a sticky._

http://kormsen.info/lgb-manual.pdf


----------

