Reversing Loop - Need Help

Discussion in 'FAQs' started by Mannix, Mar 24, 2007.

  1. Mannix

    Mannix Member

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    I do not have a feeder in the section between 1 and 3, but there is a feeder just to the right of 4 on the main line. I did not put in any feeders between 2 and 5. Yes, I have a voltmeter.
  2. steamhead

    steamhead Active Member

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    When you say to the right of four, do you mean between the #4 and the words Main Line, or do you mean between the 4 and the diverging route that goes towards the passing siding..?? You didn't say if the reversing module is connected.
  3. Mannix

    Mannix Member

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    The feeder is between #4 and the words Main Line. Yes, the reversing module is connected. When the locomotive comes out at 5, the outside rail of 5 joins the inside rail where it comes into the Main Line. Is the one reversing module supposed to take care of that problem or do I need another one connected to the right of 5 and to the Main Line? I will be signing off for tonight; thanks for all of your communications this evening.
  4. steamhead

    steamhead Active Member

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    From what you describe, i.e., trains running normally and being able to enter one end of the reversing section, you now have the correct electrical set-up. The insulated joiners you removed are now no longer needed since you put insulated joiners at 5.
    You shoud just need one reversing module. Unless there is a gremlin somewhere, I would suspect the module is at fault.
  5. EngineerKyle

    EngineerKyle Member

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    your first pic looked right to me.
  6. Gary Pfeil

    Gary Pfeil Active Member

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    Two comments, or questions: What type turnouts are you using? If they are power routing and not properly gapped, that siding's turnout could be a problem. More likely in my experience is the MRC reverse module itself. I have 9 reverse blocks on my layout and bought MRC modules for them. I've since replaced all but two with one by Tony's. And the two remaining will get changed out too. While they work (most of the time) when running diesels with all wheel power pick up, they do not work well with steam pilot wheels which are insulated. I have two MRC's that I've removed in a drawer, I will send them to you, perhaps yours is bad? Try seeing if it's the module, you could do something as simple as this: Take a piece of flextrack, cut gaps in both rails such as to divide it in thirds, wire the two ends opposite in polarity, feed the center thru the module, getting its power from either end. Run a loco back and forth, see if it works. Just trying to eliminate a possible source of your trouble.
  7. Mannix

    Mannix Member

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    Gary, I am using Atlas turnouts. I haven't had time to work on my layout for a few days, but want to get back to solving the problem that I have with the reversing section. In your example of cutting a piece of flex into thirds, can I use insulated jumper leads to get the power off of the rails on my layout for that test? Could that damage my DCC system? Since this is not a reversing loop, but only a reversing section do you think I need two reverse modules?
  8. Gary Pfeil

    Gary Pfeil Active Member

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    Sure you can use alligator clips. You need to power each end opposite polarity, to simulate each end of a reverse block. The middle section will be connected to the module. So, you'll need four leads for the ends (two each) and four more for the leads of the module. Really no different than on the layout. When the first axle of the loco bridges the gap at either end, it will cause the module to change polarity in the middle section to match the end. If the module doesn't flip, its bad. No, it won't damage the sytem. At worst, if the two polarities touch , it will trip your breaker.

    Your turnouts are not the source of your troubles.

    Reversing loop, reversing block, reversing section, all the same as far as the module cares. You just need one. Your diagram looks fine, if the gaps are good (not bridged) then only the module can be at fault. Or perhaps, voltage drop. If the module proves good in the test, try connecting a dc power pack in place of the dcc. This because you can read dc voltage with a regular meter, you can't with dcc. Read the voltage at the point the power is connected to the rails, and at the gaps at each end of the reverse block. If there is much of a drop, the module may not work correctly.

    Good luck
  9. Gary Pfeil

    Gary Pfeil Active Member

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    Sure you can use alligator clips. You need to power each end opposite polarity, to simulate each end of a reverse block. The middle section will be connected to the module. So, you'll need four leads for the ends (two each) and four more for the leads of the module. Really no different than on the layout. When the first axle of the loco bridges the gap at either end, it will cause the module to change polarity in the middle section to match the end. If the module doesn't flip, its bad. No, it won't damage the sytem. At worst, if the two polarities touch , it will trip your breaker.

    Your turnouts are not the source of your troubles.

    Reversing loop, reversing block, reversing section, all the same as far as the module cares. You just need one. Your diagram looks fine, if the gaps are good (not bridged) then only the module can be at fault. Or perhaps, voltage drop. If the module proves good in the test, try connecting a dc power pack in place of the dcc. This because you can read dc voltage with a regular meter, you can't with dcc. Read the voltage at the point the power is connected to the rails, and at the gaps at each end of the reverse block. If there is much of a drop, the module may not work correctly.

    Good luck
  10. Gary Pfeil

    Gary Pfeil Active Member

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    Now I know why some posts are duplicated, my post usually load immediately, when they don't I click again thinking I wasn't in the right spot the first time, then after a long while, two posts!
  11. Mannix

    Mannix Member

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    Gary, thanks for your reply. Hopefully I will get some time to run that test tomorrow.
  12. Mannix

    Mannix Member

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    Gary, I built my test track this afternoon and the module worked the same as it did on my layout. I am attaching the diagram of the test track. I can run my locomotive from B to A; however, when I reverse the locomotive I can come back from A through C but once it crosses into B I get a short. I have an idea that my module is defective, and I just purchased it on line.

    Attached Files:

  13. Mannix

    Mannix Member

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    That diagram is too small to read! A is the section to the far left. C is in the middle and B is to the far right. I connected the yellow wires from the module to the C section and the red wires from the module to the B section. I powered both ends from my layout, and I changed the polarity on the opposite ends. I had a larger diagram; however, the gauge said it was too large so ended up with the small one which is worthless!
  14. steamhead

    steamhead Active Member

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    Yup, sure looks like the module is bad...Did you buy it from a store or an individual..??
    A store should exchange it ( or MRC); an individual..???
    Good luck...!!!
  15. Gary Pfeil

    Gary Pfeil Active Member

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    Kinda figured it had to be bad, everything else looked good. I've had several of those MRC go bad, but haven't read about others with the same problem. They have a solenoid, perhaps they are sensitive to the position they are used in? You might try positioning so wires come out the top, or bottom, some such. Or just chuck it if you can't get a free replacement. I'm willing to send you 2 pcs I replaced with modules by Tony's. I love his. The MRC ones I have were working when I took them out. They only work reliably with diesel! My steam almost never make it thru, and yes it was only one end that gave me trouble! If you'd like to try mine, pm me an address to send them to.

    At least you know the layout is correct!