winston-salem district

[NW Mailing List]

Jeff-
Let's get back to the "automatic" feature that was,  and
apparently still is, incorporated into the interlocking  at
Walnut Cove.  The components of the interlocking  make
a decision based on one factor -- which train hits  the
approach circuit first.  There's no bias to  railroad.  There's
no consideration to priority.  There's no  consideration to
which train has the most tonnage.  Direction  doesn't
matter.  The approach circuit is an arrangement  of
signaltry that detects an approaching train.   Apparently
the approach circuit for northbound trains coming  to Walnut
Cove is in the vicinity of MP 113.   When the train  activates
the approach circuit, the components in the relay  case
at Walnut Cove start scanning.   Is there a train on  the
bisecting route ?  In this case the bisecting route had  been
Southern's Winston-Salem Division.   Is there a train  in
the block ahead ?  Once convinced that the route  is
unobstructed, the home signal ( at MP 108.8) will clear.   Only
then will the aspect of the distant signal change to be  more
favorable.
 
When NS abandoned the track Greensboro to Rural Hall,  the
bisecting route was eliminated, but apparently NS only  modified
the interlocking.  When a northbound shunts the  approach
circuit, the interlocking continues to "search"  for trains in  the
block toward Belews Creek Jct., and maybe for those  Winston-Salem
Division trains that'll never come.  
                                                                       Harry 
Bundy



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