EB3 , Sound Decoders
and Layouts
prepared by
Phillip Moore
Planning to have a fully operating
AT&SF railroad of the 50's and sound is at the top of the list.
After discussing the problem with Gary
at the MRC, we believe there my be a better way of wiring in circuit
breaker's in for all applications.
The initial thought is to say wire a
yard to one EB3 then the main to another etc... This would work if the
railroad was to only operate non-sound equipped locomotive or were the
density was very low, say 2 to 3 units but were you have the whole fleet
sound equipped a different approach is required.
The diagram below illustrates that the
yard is divided up into three sections. A eastern, western approach and
the yard central. The logic is simple, the reason we need circuit breakers
is we do not want a error in entering or exiting the yard to shut do the
whole yard. The whole sound illusion is destroyed when a operator drives
into a closed point [the most common reason a DCC layout with trip out]
and 6 locomotives all shutdown.
If of course the yard was on a
separate booster, not a problem for say the main line but again the yard
trips out with the same result. If you wanted to break up the yard as
shown in the diagram this would be expensive.
The problems of circuit breakers has
been well outline by the two Marks on the main page, so if in doubt read
it again.
The plan outlined below will by its
physical design mean that only one or two sound equipped locomotive can be
in a ladder at any one time and also only shutdown is the one at
fault. The diagram shows the loco's in the yard proper will not
shut down and neither will the one entering at the opposite end and
problems on a piece of track are rare OK.
The yard approach is were we will have
shorts, either by error or derailment. You will need to ensure that the
approach [yard ladder] extends into the yard proper by the length of the
longest sound equipped locomotive so if you operate UP Big Boys this means
450 mm [18"] so this approach may not work on short sidings.
This will work on a non sound
equipped layout also by ensuring that a simple error dose no interrupt the
smooth operation of the DCC layout and this is why we went this way at the
start.
