Questions on track bus wiring for multiple power districts........

[mfm37]

 Twisting may be recommended for long runs. With the number of boosters and power districts you won't have any runs long enough to need either separation or twisting.

We did a little NTRAK convention in Louisville last summer with over 700 modules filling 50,000 square feet. Most of those modules are wired with zip cord. Power districtsvwere kept at 80 feet or less. That's 40 feet each direction from the booster. We had some problems but none were caused by the bus wires.

That being said, you should try to separate loconet cables from the bus wires and any other AC carrying cables. When they need to cross, run them as close to 90degrees as possible.

Martin Myers

[rrinker]

 I have never seen the need to twist anything. And here's why. You twist those nice heavy bus wires. Then every 3 feet you run a pair of feeders up to the ....oh wait, perfectly parallel, always (you hope) fixed distance apart rails! What's probably more important is to have any signal wires (like the Loconet cables) cross the track power bus at aas near a right angle as possible to minimize any coupling of the track power to the control signals. Likewise the leads to any remote block detection sensors, or an AC power bus. Don't run those things parallel to the track bus.

                                                             --Randy

[Texas Zepher]

mobilman44

The lower level will have two power districts.  In my readings and from this Forum, I have learned to use 14 gauge wire for the bus, and to keep the two wires about 4 inches apart.  I have also learned that one should twist the two wires every so often to eliminate feedback (or ???), which I plan to do.  And of course I will have individual feeders to the track every few feet, and the feeders will be 20 g solid wire and short in length.  So far, am I on the right track???

The question that arose this morning was "What are the suggested ways in keeping (or not) the wires from two separate power districts apart?"   In my staging area I will have six tracks - two for diesel and 4 for freight.  These will be two separate districts but are only inches apart.  What is the suggested distance or method of keeping these two power district bus lines separate?

In my opinion twisting of the wire pairs eliminates the need for separation.   Both sets of wires should be carrying the same signal anyway (the whole point of the DCC signal bus syncronizing all the boosters), otherwise trains would have issues crossing from one district to the other.  Any cross-talk between the buses should be cross talking the same thing at the same time.  

Our club has all 8 boosters in a centralized location.  The bus wires coming from them are not twisted.  There are many places they are closer than 2" to each other, including the 2.5" hole where they all exit the area together.  We have no issues that I know of related to the proximity of these one to another.  If there is any possible issue I would think the track itself (acting as an antenna) is going to be more an issue than a twisted power bus.

[spearo]

Mobilman,

I don't worry about keeping the wires apart so long as you can tell the difference between the various wires.  I have two track buses that run right next to each other down the length of my layout, they are two seperate districts but, so long as I color code the districts its no problem.  Aside from the normal colors, black-red, I use other variations of the color scheme.  Orange - drk blue, yellow - drk green, anything that has a light color and a dark color will work OK.  My local Home Depot offers about 6 diff colors in 14 ga solid, when I went through all of those I went to a local electrical supply store and they have enough colors that I doubt I will ever run out.  If you run out of solid colors you can always go to striped colors ie; red with white stripes and black with white stripes.

[jrbernier]

  You do not need to keep the wire 4" apart, or even 'twist' them.  I have a 'twist' in mine just to make routing them easier.  You are breaking that 4" 'rule' by having rails 5/8" apart!  The main item to is have a feeder drop for every hunk of track.  I have about 150 sections of flex track and 46 turnouts on the layout - there are about 400 IDC's to connect to the rails.  I can do the 'Quarter' test anywhere in the layout and trip the PM42 power district.   My staging track are all on the same power district.  Basically each 'town' area has it's own power district.  If I derail and shut down that power in a town, it does not affect the rest of the trains on the layout.

Jim

[mobilman44]

Hi!

I'm getting close to wiring the lower level of the new HO layout.  This is my first pass at DCC, and this layout will have a Digitrax 5 amp system with extra 5 amp booster, and 4 power districts out of each booster.

The lower level will have two power districts.  In my readings and from this Forum, I have learned to use 14 gauge wire for the bus, and to keep the two wires about 4 inches apart.  I have also learned that one should twist the two wires every so often to eliminate feedback (or ???), which I plan to do.  And of course I will have individual feeders to the track every few feet, and the feeders will be 20 g solid wire and short in length.  So far, am I on the right track???

The question that arose this morning was "What are the suggested ways in keeping (or not) the wires from two separate power districts apart?"   In my staging area I will have six tracks - two for diesel and 4 for freight.  These will be two separate districts but are only inches apart.  What is the suggested distance or method of keeping these two power district bus lines separate?

Thank you,

Mobilman44