I have a loco servicing/small yard layout on a 7.5’ x 2.5’ panel that I am starting to do track work on. What sort of design should the bus wiring have for feeder wire attachment- I was initially thinking of a U-shaped 7’ run, with a third leg in the middle. Switches will be hand throws for now, but machine-operated later on. This will be DC (just to get running), converting to DCC soon after all wiring is tested and secure.
Any thoughts?
Cedarwoodron
I’d just go straight down the middle, or along one side all the way. In the middle, you’re a max of 15" run to any load. To the side, only the width of the module. That’s a very minimal run, even for 22 gauge feeders.
Is there a reason for the leg off the main bus in the middle? Usually a heavier feeder (18 or 16 gauge) will handle the load. Sometimes DCC network wiring suggests a straight through bus and to avoid any Ts, so that might limit choices in DCC. People disagree on how big an issue this can be, , but something to consider if planning on DCC in the future.
Why not go DCC from the outset? My personal belief, is that wiring is easier in DCC than DC.
For what it is worth, on my shelf layout of similar dimensions, I run one side of my DCC bus down the “left” edge and the “right” on the other edge. I then run a feeder to the respective bus wire from each piece of track. I have a separate bus for the turnout mechanisms (Tortoise). The Tortoise powers the turnout frogs through the mechanisms contacts.
Good luck on what you choose to do.
I would go ahead and wire for DCC operation from the get go. To run one DC loco it would be fine, to run two locos independent of one another, you would need two power packs and block control,so why go through all that if your going to switch anyway.
Advice given by a die hard DC 3cab control layout, no less.
Frank
My idea then, is to first run less elaborate bus wires, as per advice given, then run feeder wires and prep open spaces under switches for future machine installs. Next, check electrical continuity (as a very simple DC layout) so I can fix wiring and electrical contact issues now, before things get too permanent. Finally, get the DCC system attached and start working on increasing my DCC motive power fleet from the two I already have by working on the other DC engines and retro-fitting them one-by-one. No block wiring, no fancy control board (maybe a small one for switches and accessory lighting later), and less aggravation under the table (at my age).
Cedarwoodron
Hello all,
What gauge is good for bus wiring?
sarailway,
Great idea for running the opposite bus wires along each edge of a module.
soller,
Bus gauge should be determined by ultimate overall length of run. Basically, you want a wire heavy enough that it sees only a tiny voltage drop over that length. I used 12 guage THNN wire for mine, although it can be a bit hard to work with. Maximum run is about 40’. For a shorter run, you could use something skinnier, but do anticipate any potential for expansion. Once a bus is in and wired, it’s a big project to re-do it if you skimp on it.
cedarwoodron,
Yep, if no need for two-cab DC, just wire it up like you normally would. Keep in mind close gapping around turnouts is what really makes them “DCC friendly” but also make sure that your frogs are “live” is my advice. If every rail is fed over those short distances for feeders, you’re good for DCC if things are tied into a nice fat bus. Then all you need do is plug in to your DCC system with two wires and you should be good to go.
Cedarwoodron,
You should find this site useful, when you wire your layout, especially if you want to go with Hot frogs:
http://www.wiringfordcc.com/switches.htm
Frank
Why would this be an issue? Allan Gartner has recommendations of using T’s to keep bus wiring under 30ft per leg (one illustration has 8 legs).
I respect and use Allan’s website regularly. That’s his opinion and I actually think it’s probably a good one.
It’s just that others say straight through is the way to go.
I was merely respecting the fact that some folks disagree on the issue and it’s up to the OP to figure out what he wants to do.
This is especially so if the plan is to convert to DCC and the system he eventually wants to use has a recommendation to avoid Ts. I agree it probably won’t matter EXCEPT if the customer service people of the favored DCC system start insisting the bus wiring needs to be redone before they can really help him with a problem.
That’s merely theoretical, but I try to avoid presenting even considered expert opinion as fact when there are known disagreements on an issue. Best to lay out the differences and let the person most concerned decide for themselves.
Thanks, Mike- I was getting a bit queasy looking at the old Atlas block and switch wiring diagrams. Feel much better now, thank you.
Cedarwoodron