Wiring a new layout for DCC

[RayG8]

I am wiring a new HO layout and intend to run two busses one for track and one for accessories. The total length is 54 feet and the power will be situated about at the halfway point (27ft from power to end of track).

I am not sure what the correct AWG would be for the bus and feeders, any sugggestions?

 

 

[peahrens]

There's a table in a book I have but can't dig it out right now.  Here's a google search:

https://www.google.com/search?sourceid=chrome-psyapi2&ion=1&espv=2&ie=UTF-8&q=site%3A%20cs.trains%20dcc%20bus%20wire%20gauge&oq=site%3A%20cs.trains%20dcc%20bus%20wire%20gauge&aqs=chrome..69i57j69i58.2652j0j4

EDITED:  My layout is small, runs within 20 ft, so I just used 16awg, stranded.  Most will likely advise you use 14 (or 12).  I found the book I relied on, The DCC Guide (1st edition).  It has a general statement that most layouts can use 14awg bus, but larger and club layouts might use 12awg.  It then includes a table for 1/2 volt max drop depending on current (1, 2, 5 or 10 amps).  (The 1st edition does not clarify in the text that the table is for bus wiring, but presumeably that's why it's there.)  For 5 amps, the table shows up to 25' for 16awg (my case), 40' for 14awg, 63' for 12awg, and 100' for 10awg.  For 10 amps, the lengths are 12', 20', 31' and 50', respectively, for the same 4 gauges. 

Also weighing in is Allan Gartner at the famous wiringfordcc.com (a teriffic resource).  You can see on the following page (several topics down) that for HO he recommends a range of 12-16awg for current, though he does not give detailed instructions on length relationship.  Note he prefers solid wire, and he uses 10awg main bus because he likes the ease of distinguishing it from 14awg sub bus wires he uses.  I used stranded wire, partly because I thought the (love 'em or hate 'em) suitcase connectors I used for feeder / bus connections would bite the stranded wire more reliably than the hard core solid wire.  You might want to note that I don't have a website, so my expertise is not at the recommended level!

http://www.wiringfordcc.com/track_2.htm

 

[rrinker]

 Yes, for a 27 foot run to either side - #14 or #12 would be the best choice. Main concern is to reduce voltage drop, just about any size wire can handle the current.

 If you only ever run trains by yourself and only ever have one running at a time, maybe doubleheaded, you could get away with smaller wire and not have any issues - the reason being that there would never be a lot of current drawn even at teh far end of the wire, thus voltage drop would be minimal even with a size or two smaller wire (the smaller the wire, the higher the resistence. The higher the resistence, the more the voltage drop FOR A GIVEN CURRENT LOAD. The more current drawn, the more the voltage drop ). So a wire size the would result in a 1 volt drop with a full 5 amps drawn, would drop only .2 volts under a 1 amp load. 1 volt is noticeable. .2 volts is not. The problem comes in when you build based on today's usage and then expand later - suddenly what was perfectly adequate is a source of trouble which may be hard to track down.

                              --Randy

 

                        --Randy