Peco Electrofrog Turnouts

Discussion in 'HO Scale Model Trains' started by BudM, Apr 18, 2008.

  1. BudM

    BudM OldGuy

    Hi everyone;

    Could anyone tell me if I can safely use the Peco "Electrofrog" turnouts if I am going to use DCC?

    Many thanks for any help you can offer.
  2. TrainNut

    TrainNut Ditat Deus

    Yes. Just make sure you isolate them as per the instructions. Been there done that! Check out this thread from post #9 on for lots of useful information regarding these switches.
  3. Nomad

    Nomad Active Member

  4. pgandw

    pgandw Active Member

    Any turnout that is correctly wired to work with DC will also work with DCC. However, momentary short circuits in DC only affect the block/train/throttle where the short is occurring. And the short circuits may be brief enough to be almost unnoticeable. The following assumes you already know how to wire the turnout correctly for DC.

    In DCC, in order to protect the electronics, a momentary short circuit causes immediate shut down of an entire power district - the entire layout if there is only one power district. The DCC system and decoders normally reset themselves once the short is removed, but this reset can be a minor to major annoyance. The reset is particularly noticeable with some sound decoders as they go through the startup sequence.

    Short circuits happen in turnouts in several ways, depending on how the turnout is wired.

    A powered frog (Electrofrog turnouts are one example of a turnout with a powered frog) has to have the frog polarity switched when the turnout is thrown. In Peco Electrofrogs, the polarity is changed by which point is making contact with its adjoining stock rail. Both points are of the same polarity, so it is possible for the back of a metal wheel going past the open point to brush the point at the same time, creating a momentary short circuit. From what I understand, this short scenario is pretty uncommon with Peco Electrofrogs, but happens occasionally with older Walters/Shinohara turnouts. It happens more frequently if your wheels are out of gauge.

    The other way to generate a short circuit with Peco Electrofrogs is to approach from the frog end a turnout thrown against the locomotive. When the locomotive reaches the frog electrical section of a turnout thrown against it, a short circuit occurs, and the power district shuts down until the turnout is thrown correctly. Personally, I don't see this short scenario as a big deal. But I'm not running with multiple operators who all get stopped in their tracks by somebody forgetting to align a turnout correctly. In my case, I'd rather see the layout shut down with a short before the train derails on the turnout thrown against it. The derailment is likely to cause a short anyway.

    The advantage of Electrofrog and other powered frog turnouts is reduced stalling and light flickering because there are no dead spots like dead frog turnouts have. The disadvantage is the short circuit when running a turnout thrown against you.

    By the way, Peco Insulfrog and some older Atlas Custom-line turnouts may have their own short circuit issues. Occasionally the guard rail is located too far from the stock rail, or a wide-gauged wheel set spans the two rails that are close to each other as they approach the frog point. These two frog rails are of opposite polarity so a wheel tread that is able to touch both rails simultaneously will cause a momentary short circuit, again shutting down a DCC power district. Nail polish on the rails is a temporary cure; grinding away the closest part of the 2 rails is the more permanent cure. This is not an unknown problem with Peco Insulfrogs, especially in their code 100 track line.

    Some good diagrams of what is going on are at TURNOUT WIRING GUIDE. Instructions for modifying turnouts for fewer shorts are at MAKING RTR TURNOUTS DCC FRIENDLY.

    hope this helps
  5. 60103

    60103 Pooh Bah

    Bud: the shorting at the points is more likely as Peco have made their newer turnouts to finer standards -- the code 75 ones especially. Even with my DC layout, I have modified lots of them to isolate and switch the frog. I noticed after redoing one turnout last week that the next one in line had much wider spacing at the points (different model but same series).
    I use a lot of British equipment which often has narrower wheel gauge than NMRA standard, by about 1 mm. But we used to have problems with some of the old Atlas diesels which were supposed to be NMRA.
  6. steamhead

    steamhead Active Member

    Hi...I use all Peco Electrofrogs in my layout- medium and large radius ones. After several years of running (DCC) trains I have yet to have a problem with them...other than the ocassional short circuit that does occur when you enter a switch that's thrown against the train. But then there's really no safeguard against carelessness....
  7. BudM

    BudM OldGuy

    SUGGESTION #2-12b: Peco "Electrofrog" Turnout Is DCC Friendly In Just a Few Snips.

    Many thanks everyone for the great support here. I also found this page, (that Nomad provided),to be of tremendous help and as the title suggests, the Peco Electrofrogs are pretty much compatible with only a minor adjustments, (cuts)

    Thanks again for all your answers.

    Bud M.

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