DCC Wiring

[young modeler]

I am just starting to convert to DCC and I am wondering if 18AWG speaker wire would work for the bus and feeder wires.

[gmpullman]

Hi, Modeler

I converted my layout to DCC about ten years ago and I heard all the hype about feeder wires and substantial gauge buss wire size.

Well, experience has taught me that all the experts were right! A good solid and substantial current capacity is needed to keep all the DCC electrical gremlins away.

I have about 95% of all my rail joints soldered and I thought I had enough feeders supplying enough current (which will equate to voltage loss if not adequate) but here I am today still adding more feeders in areas where I thought I had enough.

The trains will run—but eventually you will get a place where a rail joint wasn't soldered well enough or a turnout that loses conductivity through the jumper wires or point rivets or if you add ballast the paint and glue will create a weak electrical path then you will find that your circuit breaker will not reset OR you will get a short and the breaker won't trip (worse!)

So, the best way to insure long term reliability is to bite the bullet and have a buss run that will be substantial enough for A) reliable operation; B) future expansion and C) gradual degrading of the track structure where it will no longer carry current reliably.

Wire ain't cheap but if you cut corners here you would regret it later. depending on the distance you have to run I'd say 14 gauge would be a minimum and don't be afraid to run 12 gauge which is what I have used on my layout.

Feeders should be attached to at least every other length of flex track rail, no more than six feet apart and rail joints should be soldered everywhere. On long straight runs you might get away with leaving a joint or two unsoldered if you have problems with expansion but I think that is not too much of a concern once the benchwork and roadbed have had a chance to acclimate to the environment.

This is just my experience, others may chime in with their personal experience as well...

 Ed

[Billwiz]

Definitely take the advice of these experienced modelers. I received my powercab last week, set up a simple loop and was amazed at how well it ran. So I began the track plan using "Lion's" methods (just setting up track to see what looked good and fit) and reconnected the powercab - did not run so well - too many joiners, gaps, etc. When I get the track plan finalized, I will go overboard on the feeders and bus to assure good electrical contact. Nothing more frustrating than a layout that has electrical and track issues (especially in a tunnel). Have fun, keep at it and take the advice of those on this forum.

[NP2626]

Then, on the other hand my Bus wires for my Digitrax Zephyr is what was installed for my layout when it was DC powered and is 20 gauge solid wire and I have detected no problems with this et-up since I installed my DCC system in 2002.  I would say going with 18 gauge for the bus will work just fine!  I guess if you looking for a recommended size to buy, then go with a larger gauge. 

[BroadwayLion]

Go with the heavier bus wire. LION used some copper house wire, but that is difficult to solder to. Too heavy, disipates heat too quickly, and it seems to be coated with some residue from the insulation that was stripped off. Had to clean it up with Lacquer Thinner.

LION bought 14 ga speaker wire for this pourpose, back when I still rand block control. It is all gone now, just the 12 ga bare bus. I must have rewired this layout at least three times, and I do not wnat to do it again, but....

ROAR

[peahrens]

Size needed depends on the length.  At 5A (surely the most on one bus) and 1/2 volt drop, the DCC guilde shows 100', 63', 40', 25' and 16' for bus wire of 10, 12, 14, 16 and 18AWG size. respectively.  Basis this I used 16AWG stranded (from Lowes) as my buses are all less than 25'.  I used 22AWG solid for the (usually) short feeders, and soldered many of the rail joints.  Don't forget to test once installed with the "quarter test" everywhere to verify you have the current capability to trip the circuit breakers (vs overheat things) when needed.

I do recommend the DCC Guide (version 1 is fine) at the MR shop, plus you will want this site handy for details (e.g., oodles of info on turnout wiring)>

http://www.wiringfordcc.com/wirefordcc_toc.htm

[cacole]

Our large (20 x 40 foot) HO scale club layout is wired with 16 Gauge stranded speaker wire purchased from All Electronics for the bus lines, but the layout is divided into three power districts with three separate boosters, and we have had no problems at all even when running multiple trains with lashups of 4 or more locomotives on each.