analog engines running will reverse direction because they see the
polarity change and respond to it.
To handle auto reversing, you will need two devices, one that acts as the
system polarity reference and another to detect a polarity mismatch
and correct it. If you are using two DB150s (or other Digitrax boost-
ers) one acts as the polarity reference and the other handles the
polarity reversal for the reversing section. You can also use a DB150
and PM42 to handle automatic reversing sections.
A single DB150 can be used to handle more than one reverse section
however, the unit can only fix a polarity mis-match at one gap at a
time. If more than one train is entering or leaving the reverse loops
connected to a single booster at the same time, a short will occur.
More than one train can be in the reverse loop at any time but, only
one can cross the double gap at a time.
4.9 Using PM42 for Power Management & AutoReversing
If you want the benefits of setting up power districts on your layout but
you don’t need to add more power to run more trains, you can use a
PM42 Quad Power Manager to set up sub-districts within booster
power districts. With PM42 you can separate the output of one or
more boosters into four sub-districts that can be set up as either
auto-reversing or as smart circuit breakers for short circuit manage-
ment. For more information about this option, contact your Digitrax
dealer or check our web site at www.digitrax.com.
4.9.1 Using AR1 for AutoReversing
If you have a single reversing section that doesn’t need its own booster,
you can use the AR1 single unit auto reverser to make it auto-revers-
ing.
4.10 Using DC and DCC together on the same layout
When running between DCC track sections and adjacent conventional
DC powered tracks, both rails must have insulating gaps.
The DC supply used must have some form of current control. A 5 to 10
Watt, 12 Volt lamp placed in series with one of the DC power pack
track leads will work for this purpose. This allows the DCC booster
to drive the locomotive onto the DC track with minimum interrup-
tion and stress to the booster, decoders and locomotive wheels.
When the lamp lights as the locomotive bridges the gaps it acts as a
“shock absorber” between the DCC and DC track sections. It is best
to cross these gaps quickly and not bridge the DCC and DC sections
for any longer than necessary.
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