I'm using an NCE Powerhouse Pro system. To stay within the maxim recommendation for the length of Track Busses, I'm planning the locations of the NCE PRO Command Station and a 2nd Booster such that the Control Bus is approximately 30' long. Is this a problem / must it be shorter than 30'? What is the maximum length for Control Busses?

-- Bob McGuire (bobedward@verizon.net), February 14, 2005

Answers

Do not confuse track bus wiring issues with the Control bus. There is no real lenght limits for the control bus (4 wire Telco cable) that anyone needs to be concerned about. Run the cable as long as you need so that the booster(s) are in the best location electrically to allow the shortest track bus wire runs for the area they are intended to cover.

The best place to put a booster is in the middle or geographical wiring center of the layout such that each track bus run from the booster out is not any longer than any other bus runs you make from the same booster. In other words try to make all the track wire bus run equal lengths.

NCE has a new 2005 manual out for the system that goes into more depth and dicussion about these issues.

http://www.ncecorporation.com/pdf/Sysman05.pdf

From the manual:

If you already have a layout, your existing wiring most likely can be used without problems as long as it can handle a continuous 5 amp current. We suggest a “bus” of two large gauge (12-14 AWG) wires that follow the general track route of your layout with feeder wires to the track about every 3-6 feet. For the most trouble free operation we suggest a feeder to EVERY piece of rail. Don’t rely on the rail joiners to handle 5 Amps of current. To prevent voltage drop over long runs a chart of recommended wire sizes is found below. For the hobbyist wiring up a new layout our suggested wire sizes based on voltage drop are:

Runs to twenty-five feet ....... #16 Runs to fifty feet.................... #14 Runs over fifty feet................ #12

For best results on long runs (over 20 feet), twist the bus wires about three turns per foot. There is no special requirement for routing the power conductors with DCC. If you are going to have long runs of cab bus cabling along the front of the layout you should run the track bus wires nearer the rear to prevent potential “crosstalk” between the track signal and the cab bus.

Hope this helps.

Mark Gurries

-- Mark Gurries (gurriesm@macconnect.com), February 15, 2005.