Wiring question

Kevin Anderson Sep 21, 2020

  1. Kevin Anderson

    Kevin Anderson TrainBoard Member

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    I have built this module and getting ready to lay track. I want to use it as an anchor for a return loop. Not quite sure how to wire it due to the reverse loop issue. I don’t want to start laying track until I know for sure how I am going to wire it first.[​IMG]
     
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  2. RBrodzinsky

    RBrodzinsky Staff Member TrainBoard Supporter

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    You need to have the frog in the switch controlled AND, if you loop between the two left legs, an auto reverse circuit (use a PSX-AR, not an AR-1).

    if you follow the rails, in a loop, the inner rails of the frog are connected, and the outer (stock) rails are connected — hence the reverse loop.
     
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  3. NtheBasement

    NtheBasement TrainBoard Member

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    On my DCC layout I use a DPDT to throw the switch, and have it control polarity to the entire loop as well as the frog. No auto reverse needed. Added bonus: if you forget to throw the switch you get a short instead of a derail when the loco comes back around.
     
  4. Massey

    Massey TrainBoard Member

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    This is going to depend more on where you plan on putting the reversing circuit. If it is going to be part of the loop back module then you will need to put isolated rail joiners on the ends of the module, all other wiring is as normal. But if you want this module to hold the reversing circuitry then I would isolate the tracks after the crossover and install the AR1 or what ever device at that point. The benefit to that method is there is no special wiring in the loop, just feed it power from the AR unit. But the wiring on the module above becomes more complex. The advantage of making the reverse loop the AR control is simplicity all around. Your module then becomes more versatile for a branchline, or whatever else while keeping the power standard to the rest of the layout. Personally I would wire it this way, and isolate the ends only when the loop is used.
     
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  5. logging loco

    logging loco TrainBoard Member

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    Here is what Mike says. He explains it very well. Sounds like what NtheBasement did.

     
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  6. NtheBasement

    NtheBasement TrainBoard Member

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    I didn't use an auto-reverse circuit. Way simpler, just a DPDT to throw the turnout and some wiring.
    20200922_092921.jpg
    I use Peco Electrofrogs which are power-routing. I throw the turnouts with slide switches. Piano wire mechanically throws the points and normally the switch's contacts only provide backup power to the frog. Most of my slides switches are DPDT (they were the same price as SPDTs) but I only wire up one pole to power the frog so the other contacts are unused.

    In this case the turnout is for a flood loader's balloon track. If you look closely you can see that I gapped all four rails coming out of the turnout's frog end. This was dumb - no need to gap the inside rails as they are always both the same polarity as the frog.

    All I did to provide power to the balloon track was wire that unused pole on the DPDT to power the outside rail.

    When my layout was DC I would have to stop the engine in the balloon track, throw the switch, and then reverse direction on the transformer to start moving again. Now that I'm DCC I just throw the switch while the train is moving.
     
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  7. Inkaneer

    Inkaneer TrainBoard Member

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    So, If I understand you correctly, the balloon track polarity remains unchanged but the polarity in the stock rails in the switch and the track to the right of the switch changes. Does that cause any problems further down the track to the right or does that section of track have to be isolated?
     
  8. BarstowRick

    BarstowRick TrainBoard Supporter

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    You will need to isolate both rails in your reverse loop. I would do that at the diverging ends of the switch (track switch). Leave the switch hooked up to the main line and add an AR1 to the reverse loop. As per how Mike Fifer, accomplishes this task.

    There are other ways to do this with reversing DPDT's Toggle Switches. For a manual feed, two (2) RE-DPDT on the main and the other to the balloon loop.

    On one of the Analog DC transformers I own, the reverse loop and main line is already hooked up this way with two outlets marked main and loop or better yet a Y. Why? I get to turn my engines or anything else I want to turn around. Nice for me. Works fine!

    I can only hope that helps.
     
    Last edited: Sep 23, 2020
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  9. Kevin Anderson

    Kevin Anderson TrainBoard Member

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    I was thinking only the two leads up
    To the crossing needed to be isolated since the crossing needs separate isolation as well as the switch frog. So I was thinking and AR unit for the two leads. Frog juicer for the crossing and a blue point for the switch frog. Or should I just go all frog juicers for all three?
     
  10. NtheBasement

    NtheBasement TrainBoard Member

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    The track on the right is not switched.

    One pole of the DPDT powers the frog. Electrically following the frog to the right, it connects to both point rails and via one of those at a time the frog connects to whichever stock rail the point is touching. This pole provides redundancy for when some grime or piece of ballast prevents a point from actually making electrical contact with the stock rail (which happens often enough, especially after ballasting, that I power all the frogs on my layout).

    Electrically following the frog to the left, it connects to both inner rails. If you follow one inner rail around the balloon back to the switch, it is the same as the other inner rail, so no point in gapping those.

    The other pole powers the balloon's outer rail, which needs to be gapped at both ends near the turnout.

    It follows that any feeders on the balloon have to connect to the DPDT, not the main bus.

    In operation you don't do anything extra; to enter and then leave the balloon you have to throw the turnout. The DPDT throws the points via piano wire at the same time that it reverses polarity on the frog and the outer rails.
     
  11. RBrodzinsky

    RBrodzinsky Staff Member TrainBoard Supporter

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    @NtheBasement , true, if one knows that this FreeMo-N module will ALWAYS be used with the return loop. Since it may also be used as a branch point in a FreeMo-N layout, one also needs to plan for that in the wiring and gapping. Hence my original reply. And, note: a Peco Electrofrog is not permitted as it doesn’t meet the standard. Using a DPDT as ground throw is fine.

    Kevin: as long as your crossing is gapped and wired properly, there should be no need to treat it differently. The diamond should always be at the polarity of the matching rails.
     
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  12. Kevin Anderson

    Kevin Anderson TrainBoard Member

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    Thanks! Yes this is a free-moN scale module. I have never had to wire a crossing like this before so before I lay any track I want be sure o know what I am doing. I hope to have the track plan for the loop and modules this weekend.
     
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  13. NtheBasement

    NtheBasement TrainBoard Member

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    Got it, thanks. This got me curious about Free-moN wiring standards and how this would work in both loop and branch setups in freemoN.

    Maybe I misunderstand but the description implies that the reversing circuit would drive the rest of the modules in the loop (power their bus) so that their polarity matches this module's diverging rails. But in free-moN isn't each module powered by a fixed bus?

    If OTOH the auto reverse to drives only the switch section on this module, which would require gapping all six rails somewhere on this module, it would work fine.

    I have to admit I'm confused.
     
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  14. Kevin Anderson

    Kevin Anderson TrainBoard Member

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    Here are the Free-moN standards.


    http://free-mon.wesleysteiner.com/FreemoNStandards.pdf
     
  15. BarstowRick

    BarstowRick TrainBoard Supporter

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    Before you get hung up on having to re-wire the frog in either Peco or Kato switches (not turnouts, sigh). Kato switches are already done for you. Peco Electrofrog's are set up to keep the frog hot depending on which switch point is in touch/closed to the rail. There's no need to get into all the fanatical wiring and pulling a Tool Time trick. More power, if you know what I mean.

    On the other hand there's a lot to be said for those who do. You just won't find me doing it.
     
  16. RBrodzinsky

    RBrodzinsky Staff Member TrainBoard Supporter

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    it can get confusing, especially in this case where it is not clear cut. If we have a balloon loop, as Kevin is considering, then the “module” is actually the shown piece plus whatever sections are need to complete the loop. The key is a module may contain many sections, and you only need to meet the interface and wiring standard where your module can hook to others (in this case, the right hand entry point of the drawing). So, yes, the reverser will also feed the sections of the balloon and not violate the standard.

    If, on the other hand, this is simply a stand alone branch point, then Kevin needs to provide the standard “left over right” PowerPole interface at all three track points. No reversing would be needed within the module, either. But, having a reverser isn’t a problem, since it will just maintain “straight” polarity.

    In practice, the way for this to work in a balloon, is to NOT connect the bus wires completely through the loop. At one of the section joins, simply terminate the bus (usually done by not plugging the connectors together during setup). By doing this, each section can be wired to the standard and you don’t create a short. Said a different way, not only do you have to gap the rails, you also have to gap the bus.
     
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  17. Kevin Anderson

    Kevin Anderson TrainBoard Member

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    Here is the start of a plan. Now to figure how to get it to fit. Otherwise I may have to change tactics. I’m thinking the loop will have 8 smaller modules about 12” wide and 3’ long to get a loop and to stay within the standards for 22” minimum radius curves. The reason for 12” width is I still have to haul these things in my truck with other modules. My wife has declared trailers are not allowed. .
    [​IMG]
     
  18. RBrodzinsky

    RBrodzinsky Staff Member TrainBoard Supporter

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    If the track (arc length) in each section is 36”, and with 8 sections, that is 45 degrees; your radius is about 46”, which is still a nice smooth curve. A 30” arc is 38” radius; that is about the size we have on our Devil Mountain return loop.
     
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  19. Kevin Anderson

    Kevin Anderson TrainBoard Member

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    The difficulty here is that I have never drawn and measured a curve style module. Trying to get the correct measurements has been an trip unto itself. I think I can get the 6 foot module to work setting it in place at an angle to the loop with a curve leading off of the module to fit into the circle. I want this to also have a passing siding as well so this is going to be even more fun in alignment strategies. I hope to be purchasing lumber in a couple weeks so I can get the modules built before it gets cold.
     

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