Wiring Loop

Discussion in 'FAQs' started by Bob Collins, Dec 20, 2005.

  1. Bob Collins

    Bob Collins Active Member

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    I have a 6' X 12' layout. I am working on the wiring. Can I create an actual loop with the buss wire and then tap in the power to that loop? Will the same situation work (or not work) for both DC and DCC? :confused: :confused:

    Thanks

    Bob
  2. MasonJar

    MasonJar It's not rocket surgery

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    To keep the bus as short as possible (to maximize the benefit of having a bus), run two - one in each direction from a "central" power supply.

    Simplified drawing below shows the DCC power supply (red box) and bus (red) approximating the track plan (black).

    I don't think you should create an actual loop. And yes, this will work for both DC and DCC power


    Andrew

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  3. Bob Collins

    Bob Collins Active Member

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    Thanks Andrew, I see what you are saying. I'll give it a go and see if anything melts :eek: :eek:

    Bob
  4. ezdays

    ezdays Out AZ way

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    You could run a continous loop, around and back. It may not be necessary in most cases, but I know many industrial applications where this has merit. For example, the current, or load is distributed more evenly since there are two paths for the current to run. A second application, such as in the security industry, a closed loop like this is monitored and if there is a break in any wire, the system still works, but the break is detected and reported. What's that got to do with track wiring? Well, both this conditions can be encountered. The reason for the bus to begin with is to provide a constant source voltage and a full loop is your best bet for that if you have long runs. For short runs, forget it.

    If you're going to have block switching, you won't have a power bus anyway. All power will go through the switches, then to the blocks.
  5. pgandw

    pgandw Active Member

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    Bob

    You can tie the 2 together, and get half the resistance/voltage drop with DC (good/recommended practice).

    It is NOT recommended to tie your bus into a loop in DCC. The reason is the multipath interference with the control signals in DCC will confuse the system.

    yours in wiring
  6. Gary Pfeil

    Gary Pfeil Active Member

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    Fred may know more than I, or have more recent knowledge, but I've read (at Digitrax Yahoo group, ayear or two ago) that you can indeed connect your track power bus in a loop, but do not do so with the loconet bus.

    Gary
  7. baldwinjl

    baldwinjl Member

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    I think that wiring DCC in a loop probably would not ever actually cause a problem, but the potential does exist. If you use large enough wire for the bus, the second path is not necessary, so I would not do it.
  8. Bob Collins

    Bob Collins Active Member

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    Thanks to all of you. It almost sounds like I could set up the loop to run DC and then when I am ready to hook up my DCC I just need to g9o to the far end of the layout and snip the buss at that point. I then have two separate leads from my loconet?? Am I the one who is loco?

    Bob
  9. baldwinjl

    baldwinjl Member

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    That's a perfectly valid way of doing it. The only locos are on the track!

    Jeff
  10. Bob Collins

    Bob Collins Active Member

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    Thanks again Jeff.

    For whatever reason the wiring aspect of model railroading still baffles me. I can lay track and build hills and do all that stuff, but the concepts of wiring, either DC or DCC seem to be beyond my abilities to comprehend. Gary Pfeil knows how I struggled with the idea of even getting into DCC and although I have read at least a dozen books about it, the bell still doesn't ring. I think it is sort of like me and algrebra!! :eek: :eek: :cry: :cry:

    Bob
  11. baldwinjl

    baldwinjl Member

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    The good thing is that in the end you have to understand way less about wiring to do DCC than DC, in my opinion. After that you can learn about the more 'advanced' functions as you go, and still be able to operate in the meantime.

    Jeff
  12. jim currie

    jim currie Active Member

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    Bob try this link http://doctronics.co.uk/design.htm :)
  13. Bob Collins

    Bob Collins Active Member

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    Thanks very much Jim. I'll take some time and look over the site carefully.

    Where in AZ do you hang your hat. My wife and I are going to stay in Tucson for the month of January. As cold as its been here the past few weeks I can't get there soon enough!!

    Bob
  14. Gary Pfeil

    Gary Pfeil Active Member

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    Bob, If you do as you said, why not put off cutting the bus till you determine it is a problem? I doubt it is.

    Gary
  15. Bob Collins

    Bob Collins Active Member

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    Gary, we're on the same sheet of music. I wasn't planning to cut anything until I determine that it won't work. Setting up DC for grandkids coming tomorrow was easier for me than getting out the Digitrax and hooking it up. I may be wrong, but it seems right to me :confused: :confused:

    Bob
  16. ezdays

    ezdays Out AZ way

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    Bob,

    Jim is just a bit east of Yuma, I'm in the northwest part of the Phoenix metro area. Ray Marinaccio is up near Prescott. I don't blame you for coming to Tucson, our temps up here are going to be pushing 80 for Christmas Day. Ray is the only one that might see some snow, but probably not for Christmas.
  17. Gary Pfeil

    Gary Pfeil Active Member

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    Just to clarify Bob, when I mention a loconet bus, I mean the 6 conductor data line Digitrax uses for connecting throttle jacks and other items such as stationary decoders. This should not be configured in a loop. The track power bus you are talking about can be.

    Gary
  18. Bob Collins

    Bob Collins Active Member

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    Gary, I understand. I have it all wired for DC right now. Just did a test run and two trains work just great :cool: :cool:

    Will I have the opportunity to do some railfanning in Tucson? :)

    Bob
  19. 60103

    60103 Pooh Bah

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    On whether or not the track bus may/should be looped: If you connect two power wires to a loop of track, don't you have the equivalent of a looped bus?

    I understand that the control circuit should not be looped. Do you need any 50 ohm resistors at the ends of it? :D :D (from an old ethernet man) :rolleyes:
  20. Bob Collins

    Bob Collins Active Member

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    Ethernet? Come on, give me a break. I'm an old man. I 've heard the word, but haven't a clue how it applies to this conversation.

    You need to use small words if you want me to understand. I told you I was creatively challenged :rolleyes: :rolleyes: :p :p