Wiring conventional block control for future DCC in N scale

videobruce Jan 18, 2012

  1. videobruce

    videobruce TrainBoard Member

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    I would like to go DCC, but I already have 23 locomotives that would need a full modification that I don't want to do. Trouble & expense to me isn't worth it.
    So, what I see as my only option, is to wire for conventional block control with the assumption, in the future I will go DCC with future newer units that either have the DCC included or can be switched over to DCC by drop in decoders selling the existing units if I can.

    My question is, should I 'gap' each block for both rails even though I don't need to for conventional block control now for the future and just tie all the common rail leads together for now? There are no reverse loops. The layout is a 9x19' 'J' shape.
     
  2. dstuard

    dstuard TrainBoard Member

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    Gap both rails. You can always connect the common rail feeders under the layout if you'd like, but most DCC systems are happier if power districts (DCCspeak for "blocks") are totally isolated from one another.
     
  3. Doug A.

    Doug A. TrainBoard Supporter

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    Yes, what Doug said.

    In fact, if you are wiring for common rail DC, you can go ahead and run a "bus wire" around the layout for the common wire and attach your feeders to that. Then you can just cut the bus if you decide to do power districts or block detection. (yes, semantics really except that you might be inclined to use a heavier gauge wire for a bus versus tying all the feeders together for a common connection.)

    If you do decide to do detection, keep in mind that it may not necessarily map out the same as your DC blocks so don't assume that it will. I haven't found a good guide to splitting out track for detection and signalling, but I know when I was doing it on my last layout it was different than what I would have done back in the olden days... (bwahahaha.....just kidding there with the olden days comment)
     
  4. SteamDonkey74

    SteamDonkey74 TrainBoard Supporter

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    My two cents, having helped convert a medium large club layout to DCC and, in so doing, discovered all the shortcuts the hard way, is to adhere to best practices for DC, to gap both rails at your blocks (then those can become your DCC power districts if you so choose, and in any case having double-gaps makes tracking shorts MUCH easier), and to not skimp on the wire size or track feeders. I would also say that while you are laying track go ahead and set up your switches for power routing of the frog even if you just cap off the wire connected to the frog for now and leave it for later. It's SO much easier than after the switch is installed.
     
  5. videobruce

    videobruce TrainBoard Member

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    That's what I understood.
     
  6. Railroad Bill

    Railroad Bill TrainBoard Member

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    :pbaffled: Is it possible to wire for DCC, simple layout-oval, passing siding, spurs, with common-rail wiring? Heard it's possible, but not sure. Is "parallel" wiring essential, good-to-do, or what?
     
  7. dstuard

    dstuard TrainBoard Member

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    Sure it's possible, and many folks have done that, but I wouldn't call it best practice, and you really don't save much $$ by doing so. "Direct Home" (i.e., "parallel") wiring gives you more flexibility to make additions/changes, and for a new layout would be my method of choice (plus you never need to be concerned with which rail is "common").
     
  8. SteamDonkey74

    SteamDonkey74 TrainBoard Supporter

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    I wouldn't use common rail wiring. It's really not so hard to double-gap and you'll save yourself headaches in the future. Here's Alan Gartner's "Wiring for DCC" on this subject:

    http://www.wiringfordcc.com/track_2.htm
     
  9. Alan C.

    Alan C. TrainBoard Member

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    After reading the other comments and being in your position in the past my sugestion is to go to Digitrax.com and look up the service manual for the BDL-168 (16 Blocks ) or the BD-4 (4 blocks) and go ahead and install your wiring to accomadate these boards in the future for DCC. till then just make jumper/bypass wires to make your system works for now. Point is if you don't do it now your have to basiclly start the wireing process ALL OVER . The boards I sujested work with a DC layout and also I might sugest a PM-42 Block circut breakers (4 total) per board, this board can made to preform as reverse loop up to (4 total) or a combo of both. The best think I can tell you is read, read, read, the manuals i sugested, and plan ahead not the present. I hope this helps Alan C.
     
    Last edited by a moderator: Jan 19, 2012
  10. videobruce

    videobruce TrainBoard Member

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    UP Bridges; I have seen those and considered them.
    I have been reading, reading..... Head is spinning.
     
  11. Brett_Henderson

    Brett_Henderson TrainBoard Member

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    Something to consider; assuming this is a layout under construction, and not yet wired at all.. is that there is size/complexity threshold.

    IOW, a "large" layout, with several blocks, sidings and spurs, all needing their own wiring back to a control panel full of switches, can be a, "Trouble & expense", nearing that of buying decoders, and installing them.

    Dozens (or hundreds) of feet of wire, a gaggle of DPDT switches, indicators lights, etc.. add up quickly.. compared to a single set of bus-wires, and track feeders.

    Just food for thought, especially if you're reasonably sure you'll be going DCC, eventually.
     
  12. videobruce

    videobruce TrainBoard Member

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    Yes.
    Wire is cheap, toggles from the right place aren't that expensive, same goes for lights. At least compared to what I have seen with DCC. The biggest factor would be the control panel itself. How to adopt a DC setup for DCC?
    I'm not that sure.
     

    Attached Files:

  13. dstuard

    dstuard TrainBoard Member

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    A DC control panel would have a cab selector switch for each and every block, necessitating wire runs from each block back to its selector switch. Not necessary with DCC, although you would still need to subdivide the layout into power districts to mitigate the effect of shorts.

    If you do wire for DC cab control, it is easy to replace one cab with your DCC system and throw all the block toggles to that cab. Turnout control could be the same in either case, or you could use DCC contol if you want to operate turnouts from the throttle.

    Since you are building anew, consider whether you want to spend your time running trains or flipping block toggles in advance of/behind trains. If you want to interface your computer to the layout (signalling, turnout control, CTC panel, etc.) you pretty much will need to be DCC anyway.
     
  14. Brett_Henderson

    Brett_Henderson TrainBoard Member

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    That track-plan is definately past the threshold :)
     
  15. Alan C.

    Alan C. TrainBoard Member

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    -----The first time you fly a 747 jet it very very hard. The second time you fly it you just worry about running out of gas!!!!!!!! Take care Best Wishes
     
  16. BarstowRick

    BarstowRick TrainBoard Supporter

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    FYI, my layout is wired to DPDT standards, to Cab A and Cab B for analog DC. All I did was remove the wires from Cab B and hooked up DCC. Flipped all my toggles to Cab B and I was off and running...on DCC.

    Here is my accounting of the event and documentation:

    http://www.trainboard.com/grapevine...e-Cab-A-Cab-B&highlight=BarstowRick+DCC,+DPDT

    One caution. I've had nothing but trouble with common wire applications. The only time it works for me is when I wire up the lights in buildings. I have friends who are strong proponents of common wire but you ought to see the poor performance of locomotives running in the opposite directions, at the same time. I've been waiting for them to wake up but it is what it is, while it is. Otherwise my advice, is to avoid it like the plague.

    Feel free to read how I have my layout wired and if you have any questions feel free to PM me.

    Best of luck with your wiring project and your layout.
     
  17. gtMark

    gtMark TrainBoard Member

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    All this about gapping the common rail being said, Having built the layout I have with an un - gapped common rail what are the options beside tearing down the entire layout and starting over??
     
  18. videobruce

    videobruce TrainBoard Member

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    Understood and not a problem. I plan on a CP with a mostly to scale track plan as opposed to a straight line diagram. I tried that with my 1st layout and it was too confusing.
    Again no no problem. Gives the ability to 'go back' if necessary for some unknown reason.
    That is major issue and a stumbling block, but so are 29 engines that would be tough to convert to DCC.
    Nope, not in the least. I like computers, but not with trains.
     
  19. videobruce

    videobruce TrainBoard Member

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    gtMark; just use a Dremel tool to gap where you need, drill holes for wire and solder feeders to those points.
     
  20. BarstowRick

    BarstowRick TrainBoard Supporter

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    The problem with the word "Common" is it has to many applications. It would be better if we spoke of it as a "Neutral" or "Negative" as in polarity, when discussing wiring techniques.

    Atlas developed the thinking behind the "Common" but doesn't exactly share with us disclaimers or discloures, as to the limitations or poor quality of train operations. We've been left to learn that on our own.

    One question I've always asked, what happens to the "Common" or "Neutral" when you change the polarity on the transformer? I've heard all the answers out there but that never did solve the poor performance of my locomotives.

    Take it from someone who fought with the "Common" and finally pulled it off his layout and went to Double Pole Double Throw Toggles. It was the END, of all my operational problems and poor locomotive performance. Now, I could run two trains in the opposite direction...no problems. Disclaimer, as long as they stayed in the blocks as per cab assignment.

    Anyway, best of luck with your wiring project. Don't let it get the best of you. Sometimes, it can be hard to wrap your head around what it is you need to do. You'll get'r done.
     

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