4.0 Installing Digitrax On Your Layout
Early proponents of DCC touted the fact that you can hook up your railroad
with just two wires. While this is technically correct, there are some things you
will need to consider to get the most out of Digitrax Command Control.
Because the DCC signal and the power that runs the trains are one in the same,
you must provide adequate power to all areas of your layout for reliable DCC
operation. If the decoder in the locomotive does not “see” track power, it will
not see the DCC signal and it won’t run. Digitrax boosters need enough track
power to sense short circuits to operate properly. Your layout must have a
power bus and feeder system that can safely support the continuous full current
rating of any booster anywhere on the layout.
The good news is that if your current layout runs with regular DC then it will
probably run on DCC.
Unless you need to set up power districts on your layout
for added power, the only gaps you need are for hard shorts like reversing dis-
tricts & uninsulated frogs. If you are already wired for block control, you prob-
ably don’t need to rewire. Just open all your blocks so that the entire track has
power & you are ready to go. If you are using common rail wiring, we recom-
mend that you divide the layout into power districts by double gapping
between power districts.
4.1 Direct Home Wiring vs. Common Rail Wiring
Digitrax strongly recommends direct home wiring where each power district
and its booster are electrically isolated. This type of wiring is safer and more
convenient to work with for debugging and for adding reversing sections and
detection later.
If you are planning to use whole layout common rail wiring,
please have your dealer special order opto-isolated boosters for your layout.
Note for detection and signaling wiring common rail can be used within power
districts that are wired for direct home and use regular Digitrax boosters.
Remember, no matter how you control your trains, you should always use safe
wiring practices.
4.2 Recommended wire sizes for power bus & track feeders
On an average size layout Digitrax recommends that the power bus from
the booster be at least 16 AWG. When feeding areas up to 50’ from
the booster, we recommend using 12 AWG wire for the power bus.
From the main power bus, we recommend dropping feeders (22-24
AWG) approximately every 6 to 10 feet of track. Sets of feeders
should be wired to both rails and we recommend at least 2 sets of
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