DCC Impulses Column - 6
consist has BEMF enabled and runs smoothly. The one that
does not have BEMF enabled has three identical era Stewart F
unit models but the engines have different-vintage decoders
with different BEMF designs. Disabling BEMF for the group was
finally my choice to achieve the desired performance without
changing decoders. If I were to put TCS A4 decoders in all locos,
they would run fine with BEMF enabled. The same holds true
if I were to put a SoundTraxx Tsunami in one loco and “Tsilent
Tsunami” (motor and lights only) decoders in the others.
Let’s look at the majority of the club consists that run flawlessly
with BEMF enabled. Within each consist:
They have the same manufacturer, vintage, and model locos.
For example: Life-Like Proto 2000 GP20 models from a light
blue box.
They have the same model and vintage decoders. For exam-
ple Digitrax DN-143 decoders.
They have the same settings for momentum (acceleration
and deceleration).
They were speed matched with BEMF enabled (see my
column):
They start to creep on a low speed step (lower than 5 out
of 128)
They would run several yards at top speed in both direc-
tions and not close up a space of a few inches.
They are speed limited to about 40 SMPH, plenty fast
enough for operations on our layout.
Even though we have a Digitrax system, they are consisted by
advanced decoder-based consisting, see my
column for more information.
Did it take some time fiddling with them (using DecoderPro)
to achieve this result? Definitely. Was it worth it? Yes, I believe
so. They pull smoothly around the layout (most are used
on through freights, running from staging to the main yard,
exchanging cars and returning to staging).
7. The command station shuts down
when the booster sees a short
My friend, Ross Kudlick, contributed this myth.
Lenz provides a way to overcome this. Connecting the E ter-
minal between their boosters and their command station will
force a shutdown of the command station if any booster stops
supplying power due to either a short or overheating.
This makes no matter on a layout with one command station
and one booster. If the booster has shut down, the fact that
the command station continues to run is immaterial.
6: Consisted locos on the PCMRC layout – consistent
loco and decoder design and attention to detail allow
them to run together with BEMF activated.
6
MRH-Mar 2014
