Track section module MX9 Page 19
routes should not overlap each other, if such parallel movements are desired. In some cases a sec-
tion may consist of just one turnout. This is especially true for double crossovers.
MX9
MX9
L
H
CAN bus
Track power bus
Directions
F L H
These sections
are not usable
H L
H L F
H
Fundamental considerations -
when planning track sections in complex situations:
The previous examples dealt with some basic track configurations. They can’t be used as an illustra-
tion for every conceivable station or line. The designer has to keep certain principles in mind when
planning his or her layout. These are as follows:
•
A stop section has to be provided for every stop point intended at the end of a route or block. See
example #1 for stop section length.
Direction
H
a l t ( s t o p ) s e c t i o n
Desired stop point
Typical signal location
Safety margin
Stopping distance
•
Low speed sections are placed before a stop section in order to slow down a train before it enters
the usually short stop section. Low speed sections can later be assigned to speed step L (= low
speed) or U (= ultra low speed) during the route definition.
Reducing a train’s speed improves the accuracy of an intended stop point. The accuracy increases
the slower the train is before it enters a stop section. It follows that a stop section may be shorter
with a low speed section set to speed step U as compared to speed step L.
Dire ctio n
F H
D esir ed stop point
F L H
F U H
F L U H
Following
blocks
End of a block or route
•
F, H, L and U sections can be assigned to track sections in any sequence that is practical, e.g. to
place the low speed and stop sections in the proper order and length when used in both directions.
Obviously, the L and U sections have to be long enough so that the train has enough time to actu-
ally decelerate to its intended lower speed before it enters the H section.
•
Track sections when used in route or block control must not belong to more than one active route
at a time, with the exception of two consecutive routes overlapping each other. Therefore no track
section may be part of two routes that can be activated at the same time.
•
The two subsections of a MX9 main section can be connected to track sections that will need the
same speed limit applied to in all operational circumstances (F, L, U, and H).
Several sections are needed to operate parallel
routes simultaneously
Such a section is not practical !
•
This will be the case with track sections in a block or a platform track. If for instance a bidirectional
platform track is made up of three sections, any two sections may be selected as one main section
and the remaining section connected to another main section. The other half of that main section
has to remain unused. It makes sense to select the two stop sections as a main section when train
number recognition is employed.
L
H
H U H
A B
A B
or
One main section second main section
•
Carefully consider which sections in a turnout area should be joined to one main section:
These two sections, on the other hand, may
be part of the same main section. All conceivable
routes that are practical include both sections.
If a route is selected that includes only one of
them no other route can be set at the same time.
These track sections must not to be part of the
same main section since each of them could
be part of a different route at the same time.
Unless, of course, parallel entry and/or exit
operations are not intended.
FOR FURTHER EXPLANATIONS TO TRACK SECTION ZONING –
Consult the STP manual !
