Wiring Help?

Can someone tell me what size wire I should use to wire my layout. The layout is 8x12 with no reverse loops. I have some 20 gauge solid wire is this to thick? And one more queston if you don't mind, what are suit case conectors and are they good for wiring the layout and if so whre do you buy them. I'm just starting out in the model railroad scene. Hope someone can help. Thanyou very much!

Reply to
Irish Rouge
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I would recomend if it is G #12 if O #18 if HO #16 if N #14.

Reply to
Charles Kimbrough

There was a thread on suitcase connecters here a couple of weeks back. If it's already expired from your news provider you can do a Google search for "suitcase" in this newsgroup. You might also try a search on "wire." I remember reading something on wire sizes in the past couple of weeks.

Reply to

That will probably work fine unless you want to run multiple engines and/or if you use DCC. I'd suggest you buy one of the basic "Wiring your model RR" books to see what your options are per your own planning.

Cheers and enjoy the hobby, Bill S.

Reply to
Bill Sohl

The bus wires from the power source (or control panle) to the local block/rail connections should #14 or larger (ie, lower numbers). The connections ("feeders") from the bus wires to the track can be #20 or even smaller, but #24 is the recommended limit.

A "suitcase connector" is a plastic and metal gizmo that connects two wires by puncturing their insulation. You place it on the wires to be connected and squeeze it with a pliers or purpose-made tool. Any good electrical/electronics supply store will have them, and the sales help should be able to tell you more.


Reply to
Wolf Kirchmeir

I asked the same question several weeks ago and received a lot of good advice from the group.

The most consistant recommendation I received was for 12 gauge for the bus and 18 or 20 gauge for the feeder wires. I started with18 gauge feeders but because I don't solder well, I switched to 20 gauge which was a little easier to work with. Since I have only a small layout I wish I had used 14 gauge for the bus for much the same reason.

Finally I tried the suitcase connectors and they solved a lot of problems and I'll be using them whenever possible from now on. I found that I could made a good connection with two different sized wires by folding the smaller over to double it's size. Radio Shack calls them Tap-in Squeese Connectors.

Hope that helps.


Reply to
Carter Braxton

I.R. :

See this table:

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You will note that they give 2 current ratings for 20 gauge wire: one for a bundled wire (poor air circulation) which is about 1.5 A, another for a single conductor on a chassis (good air circulation) which is 11 A!

The 'bundled' rating is EXTREMELY conservative. The National Electrical Code allows

20 A in a 12 gauge 2 wire cable, rather than the 'bundled' rating of about half that. Your layout wires, hung in the open air under the table, are well-cooled, so I would say 3 A for the 20 gauge wire is fine. This is enough to run about 3 HO locomotives; your usual cheapie HO power pack delivers up to 1 amp.

Now, since the resistance of this 20 ga copper is about 10.15 ohms per thousand feet, we can use Ohm's Law to calculate the voltage drop at this rated current:

E = IR

E = 3 A * 10.15 Ohms = 30.5 volts per thousand feet.

It will take this potential to push a 3A current through a 20 gauge wire 1000 feet long.

With an 8 x 12 layout, the longest needed bus would have to go all the way around the table perimeter, and be 2*8 + 2*12 = 40 feet long. Using the above voltage drop, you get a 1.22 volt drop at the farthest point; half that if your bus is a continuous loop and the current only has to go halfway around.

Wire of 14 AWG has about a quarter the resistance of 20 AWG and is rated by the NEC for 15 amps in a cable. Using 14 AWG, your voltage drop as calculated above would be around .31 volts at the farthest point, instead of 1.22.

Since it's easy to get 14 gauge solid wire (type THHN, at your hardware store) it's probably best to use it. It will probably be cheaper than the 20 gauge, anyway. Suitcase connectors, to my mind, aren't really necessary for model railroading. Just twist the wires together tightly and tape. To connect to the bus, wrap and tape. Solder if you can - it's cheaper than any solderless connector. If you can't, just buy a soldering gun and learn how; it's an easy and very useful skill.

Cordially yours: Gerard P.

Reply to

My self, I prefer wire nuts for 3 reasons;

1- they are available in several sizes 2- It's easy to remove or add a wire to the circuit 3- They are inexpensive and available in bags 4- Any Home Depot, Lowe's or hardware store has them

OOP's, that's 4!!!

David J

Reply to
L.Hamilton Silkitis

Thanks to everybody for the help, now the only thing left to do is get th blow torch out and start welding!!! No just kidding.

Mike aka I.R.

Reply to
Irish Rouge

Not trying to be a smart aleck but shouldn't that be:

G #12, O #14, HO #16, N #18

The smaller the number the larger the conductor (wire).

Ruppster sportster at dodge-semis dot com

Reply to

Reply to
Charles Kimbrough

No, because the smaller the scale, the more locomotives you can fit into a given space. You can actually end up with more current draw in N scale than in G, because of having FAR more locomotives active - not to mention lighted passenger cars.

This is why N-Trak has recently issued a new RP calling for 12 AWG wire for the mainline busses. See:

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Reply to
Joe Ellis

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