reverse look, but no loop

Discussion in 'DCC & Electronics' started by daboonk, Feb 21, 2005.

  1. daboonk

    daboonk Member

    Joined:
    Dec 12, 2004
    Messages:
    69
    Likes Received:
    0
    thanks for your help
  2. nolatron

    nolatron Member

    Joined:
    Nov 17, 2004
    Messages:
    750
    Likes Received:
    0
    I'm looking into setting up the same thing pretty much with my DCC layout. I don't have enought room to add a reverse loop or wye, so a simple 'crossover' might do the trick if it'll work with the proper wiring with an auto reverser like this.

    AR1 Auto Reversing Controller
    http://digitrax.com/prd_powerman_ar1.php

    Here's a diagram as well. Same type of setup.

    Attached Files:

  3. daboonk

    daboonk Member

    Joined:
    Dec 12, 2004
    Messages:
    69
    Likes Received:
    0
    yea, thats exactly what i need to do
  4. 60103

    60103 Pooh Bah

    Joined:
    Mar 25, 2002
    Messages:
    5,141
    Likes Received:
    0
    If there are no further complications (yards, passing sidings), you will need to insulate a section at least a train length long, one end will be at BOTH ends of the lower switch (the part past the frog) and the other end somewhere around the loop before it gets to the other switch. This loop will not be connected directly to the bus wires but to the reverse loop module which is then connected to the bus wires.
    When you go into the reversing section, the module will flip the "polarity" to eliminate any short circuit. When you go out again, it will flip the "polarity" the other way.
    If you decide to put a crossover in the other way, you will need another block or a slightly different arrangement.
  5. 60103

    60103 Pooh Bah

    Joined:
    Mar 25, 2002
    Messages:
    5,141
    Likes Received:
    0
  6. colin

    colin New Member

    Joined:
    Feb 10, 2005
    Messages:
    24
    Likes Received:
    0
    reverse loop

    so am i correct in saying that the crossover (the part in red in nolatron's diagram) has to be a train length long. so this would not work for two tracks side by side. (the dogbone) unless the section of crossover track was about 6 ft long?
  7. Gary Pfeil

    Gary Pfeil Active Member

    Joined:
    May 8, 2001
    Messages:
    2,594
    Likes Received:
    0
    daboonk, what you've drawn is basically what my layout is, in my case the two parallel tracks are pretty long and there are several sets of crossovers. If you look at the wiring suggested by Railway Bob, you will note he connected both "north" rails to one bus and both "south" rails to the other. This makes the crossover no problem electrically. And is the way I wired mine and the way I tried to descibe in one of my earlier posts. However, the two turnback curves have to be isolated on both rails if you use this method, and each is a reverse block. I feel this is the best way to proceed. Yes, you have two reverse blocks, requiring either two reverse modules or one reverse module and the stipulation that you only enter/exit one reverse block ata time. If you don't wan the restriction of only being able to enter/exit one reverse block at a time, and don't want to buy two reverse modules, then do as David mentioned and make one reverse block as he described. If you do this, do not wire the two parallel tracks as Railway Bob suggested, wire them the same way you would have done with DC, that is, opposite polarities. This way the return curves are not reverse blocks.

    Gary
  8. 60103

    60103 Pooh Bah

    Joined:
    Mar 25, 2002
    Messages:
    5,141
    Likes Received:
    0
    Colin: the crossover does not have to be a train length. It is the part starting in the middle of the crossover, going around the balloon loop and stopping short of the other turnout that we're talking about. Requires double gaps (both rails) between the turnouts of the crossover and just beyond the straight leg of the turnouts at the frog end.
  9. Gary Pfeil

    Gary Pfeil Active Member

    Joined:
    May 8, 2001
    Messages:
    2,594
    Likes Received:
    0
    To clarify Davids accurate answewr, the crossover doesn't have to be a trainlength long, but a reverse block does, which is why he descibed the block as he did originally. The reason it needs to be a train long is that metal wheels crossing the gaps at both ends at the same time is a bad thing. However, I believe there is one auto reverser that does not require a train length block, that is Loys Toys unit. Unfortunately, I don't use them and have no idea how it is they work, or what other requirement they may have. You may want to check his website, ought to be www.loystoys.com

    Gary
  10. daboonk

    daboonk Member

    Joined:
    Dec 12, 2004
    Messages:
    69
    Likes Received:
    0
    thanks guys
  11. Dansco

    Dansco Member

    Joined:
    Feb 26, 2007
    Messages:
    106
    Likes Received:
    0
    Sorry, I just don't see the reverse loop!

    Out side rail of the inner loop is connected to the outside rail of the outer loop, thus outside is always outside, inside is always inside.

    I created a simplified version of your layout in RTS, good for checking for short circuits.

    The first image shows the cross over is NOT a short, therefore does not require any reversing module.

    The second image shows a balloon loop to demonstrate where an auto reversing module would be needed.

    Thanks
    Dansco

    Attached Files:

  12. Dansco

    Dansco Member

    Joined:
    Feb 26, 2007
    Messages:
    106
    Likes Received:
    0
    Lol, I just noticed I replied to a three year old thread.. whops.

    Maybe someone will find it useful anyway.

    Thanks
    Dansco
  13. Gary Pfeil

    Gary Pfeil Active Member

    Joined:
    May 8, 2001
    Messages:
    2,594
    Likes Received:
    0
    Dansco, the only thing is your track diagram is not the same as the one the origianl poster posted.