DCC IMPULSES |
11
So, I recommend staggering the gaps. The minimum I like to see
is ½” in HO or smaller scale and an inch in larger scales. There
is really no maximum distance – go for what is convenient. Just
remember that the length of the loop is the distance between
the closest gaps.
I have adopted a practice of offsetting gaps every time I need
an insulated section. It doesn’t matter whether the gap is for
district blocking or a reversing loop. Down the road, you may
want to turn a block into a reversing loop. The gap shown in [6]
is between power districts, not part of a reversing loop. I did the
gaps for my loop the same way, though.
Another “gotcha” can come when adjacent districts are con-
nected to auto-reversers. You need a section between loops that
never changes polarity -- that is, wired to the bus not through
ADVERT I SEMENT
DCC IMPULSES |
12
an auto-reverser. Think about floating boat docks. If you are
trying to step from one floating dock to another, it is easier if
you can go to a fixed dock in between. Similarly, if you have two
reverser-wired sections next to each other, you can set up a
war between the reversers, each one reversing and still seeing a
short. Even a few inches of non-reversing track will help.
Choosing an auto-reverser
In my November 2014 column, I recommended placing circuit
breakers between the booster bus and the track bus to protect
the rolling stock. Similarly, I prefer to use auto-reversers that con-
tain their own circuit breaker. Amazingly, many auto-reversers do
not contain this easy-to-implement feature.
Auto-reversers with circuit protection are available from DCC
Specialties, both the PSx-AR
and the OG-AR units. I know
of no other auto reverser that
includes the circuit protection
function, including units from
Digitrax, Lenz, NCE, MRC or
Tam Valley Depot.
In the photo of my RMP
control board [7], on the left
are two PSx circuit breaker
modules. On the right is a
PSx-AR auto-reverser. Since
the PSx-AR combines the auto-
reverse and circuit breaker
functions, all are wired to the
ADVERT I SEMENT
