Help with MRC Reverse Loop Module

Discussion in 'DCC & Electronics' started by planeshavings42, Nov 18, 2007.

  1. planeshavings42

    planeshavings42 Member

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    :curse:Hello all, I have just picked up a few MRC's reverse Loop module's, AD 520, and when I hook them up as the directions suggest, my diesels all run fine, but when I try my Challenger 4-6-6-4, it stops and after a few seconds it takes off and runs fine again, has anyone on the gauge run into this problem, and found the solution? wall1
  2. woodone

    woodone Member

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    Who's DCC system?
    There might be a set point (voltage-amps) that need to be changed,
    The Challenger will draw more amps because it has sound.

    BTW what Scale are we warking with?
  3. baldwinjl

    baldwinjl Member

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    This is a guess, having neither the AD 520, nor the Challenger!

    Your booster/command station is seeing the short before the reverse module can react. I would guess that this is because the Challenger is drawing more current to begin with,hence is closer to setting off the command station to begin with. So, there are two ways to address this. Either the command station has to react to a short more slowly (some have this capability) or the reverser has to detect the short more quickly, or at a lower level.

    Also look at page 15 of this:
    http://www.modelrectifier.com/resou...ADVANCE TIPS AND TRICKS REVISED 05-03-07.pdf
    (Not knowing what system you are using it may not apply).
  4. planeshavings42

    planeshavings42 Member

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    Hello Woodone, I'm working with HO Gauge, and my system is MRC Prodigy Advanced, Thank you, and any advise will be well appreciated.

    Duane Hampton
  5. planeshavings42

    planeshavings42 Member

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    Hello Woodone, I'm working with HO Gauge, and my system is MRC Prodigy Advanced, Thank you, and any advise will be well appreciated.

    Duane Hampton
  6. planeshavings42

    planeshavings42 Member

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    Thank You, baldwinjl, you guessed it, I'm using an MRC Prodigy Advanced system, and I think you have hit the nail on the head, but I still don't know what to do to correct the problem. I have gone to MRC, and read all they have on the Prodigy Advanced system, and didn't find anything about a slower short reaction time, and as for the MRC AD520 Reverse Module, I don't believe it is adjustable, and their web site doesn't list any further information on the module. I think my next choice will be to go to MRC, and explain the problem to them, and see if we can figure out what to do. I highly appreciate all of your input from all.

    Duane Hampton
  7. baldwinjl

    baldwinjl Member

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    I think they'll take more or your money and up the current output capability of the PA (I think that's what it said in the .pdf) That day the reverse module will see the short before the PA kicks out. Another option would be a module that has some settings, but since you already have the one you have, I don't see the point. with the Challenger, you are probably going to wany more current available, anyway.
  8. planeshavings42

    planeshavings42 Member

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    Thank's again baldwinjl, but as far as changing module manufactures, I am pretty well stuck, as I have bought 5 of them, as I have 5 reverse loops in my set up. Duane
  9. baldwinjl

    baldwinjl Member

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    Then the option is to call them and find out how to get their stuff to work together!

    Jeff
  10. Gary Pfeil

    Gary Pfeil Active Member

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    Does the lead pilot wheel of your Challenger pick up power from both rails? Have you tried any other steam? I had the same problem with MRC reversers and concluded, but did not prove, that they only work reliably when the first wheelset to cross the gap picks up power from both rails. All my diesels pick up from all wheels, and all worked fine. None of my steam with metal pilot wheels would activate the reverser. I tried to activate the reverser by shorting out the rails with screwdriver tip, this would not trip the reverser, just my circuit breaker. Now, perhaps this had something to do with the ladder of turnouts leading to the reverse blocks (storage loops) causing voltage drop at the gaps, tho I eventually soldered additional feeds to rectify that possibility. When I switched to Tony's units (no longer avail) I no longer had this problem.
  11. woodone

    woodone Member

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    I would have to agree with Balwinjl- We just went through this same thing with TrainNut last week. He found a problem with his Zephyr system. It would shut down the system before the reverse dector would switch over. He had a reverse module that had a trip set point, and even after setting it to a lower set point the Zephyr would still shut down before the reverse module would make the switch.
    He had the Zephyr repaired and the system and revese loop works fine now.
  12. baldwinjl

    baldwinjl Member

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    I think the MDC reverser may take 'too much' current relative to the output capacity of some DCC systems, and is 'too slow', relative to how quickly some systems detect a short a shut down. In theory, the reverser should detect when any metal wheel bridges a gap between the reversing section and the 'normal' section. But because of the slowness and lack of sensitivily Gary's theory may make sense. I can't quite convince myself, but I can't quite convince myself it doesn't.

    Tony's reverser has morphed into DCC Specialties reverser, it is the next generation of the same design, and now you can buy from places other than Tony's, Litchfield Station, for example.

    Jeff
  13. Gary Pfeil

    Gary Pfeil Active Member

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    Jeff, for what it's worth, my dcc is one of the early Digitrax chief systems, at 5 amp. It has an internal switch for the reaction time of its breaker, I had it set to its slowest and there was a difference, when at the faster setting even the diesels did not always activate the MDC reverser. However, one of the things Tony told me back 5 years ago was that it would be preferable to have the reverser work at the faster breaker setting, if possible.
  14. baldwinjl

    baldwinjl Member

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    Sure, given the choice you want the breaker as quick as possible, while still allowing the autoreverser to function. And in this case, it clearly doesn't work. I believe the MRC autoreverser is notoriously slow, and some of the MRC 'starter' systems are fairly low current, so you have a pretty good chance of the autoreverser not reacting before the booster kicks out. With the 5A system, the reverser has a better chance, but as you discovered, the MRC is still really slow. What bothers me the most about this whole thing is that MRC puts out products that should be 'plug and play' and they won't even work with each other, let alone other systems. It's giving me a clue about what not to buy!

    Jeff
  15. baldwinjl

    baldwinjl Member

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    Rereading what you wrote, I think we are in complete agreement, the MRC autoreverser isn't real sensitive, and pretty slow.

    JEff