DCC Impulses Column - 8
loco on your layout. There is no reason to remove all the locos
from the layout or any such drastic measure when using POM.
Blast mode is the “nuclear” option. It will reprogram any
decoder that sees its commands. It is designed to globally set
things like acceleration rates or to recover decoders that seem
to have totally lost their way.
Understand that, without the rare installation of bi-directional
layout communication, like Digitrax’ Transponding or Lenz’
RailCom, you cannot read back CVs from your decoders using
POM or blast-mode programming.
There are two cases where hardware creates similar situations
and can reprogram every loco on the layout.
The Digitrax DB150 has a very limited command station func-
tion. It has no programming track connection. As such, it can-
not read back CVs. It also uses the layout as its programming
track – sort of like a hardware version of blast mode
programming.
The NCE PowerCab has a single 2-pin track connector. It
functions as the DCC track bus for the most part. When
the PowerCab is put into service-mode programming, that
single output becomes the programming track. If you use
an external booster, like the NCE SB5 or a Tam Valley Depot
booster, this possibility is eliminated. The PowerCab loses its
programming abilities while plugged into a SB5 and the Tam
“Assure that you are, indeed, program-
ming-on-the-main. Your system should
ask for an address to receive the data. If
you aren’t asked for an address, beware.
Don’t use address 0, as you’ll probably be
in blast mode.”
8: PowerCab POM screen asking for locomotive address.
8
MRH-Mar 2014
