Just began my first model railroad project and after reading as much as i can on running DCC I am ready to begin wiring. I was hoping someone could confirm my plans…just to make sure im on the right track!
I have a small n-scale 3x6 layout (around 40-45’ of track) which i will have wired as a single block with no reversing (basically an inverted figure 8). I intend on using 12 AWG for my bus wire and 20 AWG for my feeders. I plan on placing feeders around every 5’.
Does this sound reasonable?
Also, with this configuration, is it necessary to insulate any of my track? (besides the programming track)
As far as I can tell from your post you have it in the bag. I would break the layout into blocks so that if there were a short in one area I could still run something somewhere else. Wouldn’t be a bad idea to put a toggle switch between the track and the power source (command station) so you can cut the power super quick in the event of trouble.
It’s a bit overkill but it should work fine. You might check with other N scale modelers to see how much difficulty you will have connecting 20 ga. feeders to N scale track. You also didn’t say whether your feeders are solid or stranded wire. Mine is HO scale and I used 18ga solid but mainly because I had so mich of it lying around. I could have easily gotten away with much smaller. You’ll get debates on stranded vs. solid. Solid is harder to bend and work with in tight places but you don’t have to worry about strands touching things you don’t want them to.
Personally and technically, I think that for a layout that is only 3 x 6, your wire sizes can be smaller. The 12 gauge bus and 20 gauge feeders are usually quoted for small room size layouts and larger.
The length of your main bus will be 18 foot max.(once around the layout), so you should be able to use 16 gauge wire for that. AWG 16 has less than a 5% voltage drop in 20 feet, which is acceptable. If you attach the Booster wiring to the center of the bus, the voltage drop will be even less. For your feeders, you could go with 22 gauge wire, which will be easier to use and less to see, since you are using N scale. Your feeder length will usually not be longer than 12 inches. At 14 Volts, the allowable 5% voltage drop is .7, but in actuality the voltage drop will only be approx .04 volts. Feeders about every 5 feet is good.
The above figures were gotten from “Wiring and Cable Designers Handbook” by Matisoff. I am a retired electronics technician.
I am adjusting my plans and going with the smaller gages and I am planning on using solid wire.
One question on creating blocks…
Do i understand correctly that if i use seperate blocks i have 3 choices for short protection:
Seperate boosters
Circuit Breakers
Or a device like a tail lamp.
If so, does anyone have a preference? It’s a small layout but i plan on using it as a way to practice techniques before i take over the basement for a larger one! [swg] In other words, there is room for overkill if i learn something from it…
Again, thanks for everyones time! This forum has been a great source of info for a beginner!
I haven’t used tail lamps yet but I probably will also as my HO layout progresses and grows.
When you start your larger layout, go to 12 gauge wire for the main bus. The 22 gauge wire will still be a good choice for feeders. I am using 22 for my HO feeders also. Typical decoders these days are rated for one amp. This is in HO as well as N scale, so I think 22 gauge feeders are OK in either scale as long as they are 12 inches or less in length. Of course if you can make them shorter, the better off you will be.