reverse polarity

Discussion in 'HO Scale Model Trains' started by bspun2, Mar 12, 2007.

  1. bspun2

    bspun2 New Member

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    ok i've come to a spot where the polarities reverse i'm wiring for dcc what do i do?
    wall1 wall1 wall1 hamr
  2. steamhead

    steamhead Active Member

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    Hi,

    The section that is bridging the line and reversing the polarity should be isolated using plastic rail joiners at both ends. There should be a separate feed to this section routed through a DPDT switch wired to reverse polarity. Or you could use an automatic polarity reverser in place of the DPDT switch. This is the easiest, but also the costliest option. Your choice.

    Good luck...!!!
  3. bspun2

    bspun2 New Member

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    automatic polarity reverser takes the place of the dpdt switch right?
  4. steamhead

    steamhead Active Member

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    That's correct. Also make sure that the isolated section is long enough so that a passing train, particularly one with metal wheels, doesn't bridge the gaps at both ends at the same time.
  5. 60103

    60103 Pooh Bah

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    The "black box" DCC reversing module is an electronic DPDT switch that reverses itself when it senses a short circuit. There is inteersting fun (sounds like a telegraph office) if there is a different short in the reversing section.
  6. Tommybza

    Tommybza Member

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    Hi
    It seems like i have a simmilay issue with polarity > I have been working it and so far so good .
    This is my first attempt at a Table Ho , 4x8 sized to 10 by 6. L shape Ok learned about wiggel room , thats good ,thank you
    one thing i did not think about was our fish tank ,It leaked about 3 gal. and leaked threw the floor Directly onto the table . yep ,I was thinking about foam now it the time ,Yes i do have a small question .what foam is good ? I would like to use two 1 inch peices for cutting and so on . .
    tommy.
  7. Spawn of Chaos

    Spawn of Chaos Member

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    Leaky fish tank, ouch. Did the fish survive?
  8. Tommybza

    Tommybza Member

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    Oh shure , The fish are great . the only thing is the ballist needs to be replaced ,that is fine . I just would like to use foam then go at it again . maybe move the tank to other side of the room .
    Tommy .