Signal questions 1

[NW Mailing List]

I've been looking at NW/NS pictures on http://www.railpictures.net and
noticed some things that raised questions in my mind that I am hopin y'all
can help explain. The first one has to do with a seemingly out-of-place
style switch.

The image is http://www.railpictures.net/viewphoto.php?id=205246&nseq=26
and was taken at Rawl in 77. It shows a a traffic-light style signal
ostensibly governing the movements on the siding next to the main. This
signal looks more like something you'd see on the C&O, SOU or NKP than our
beloved CPLs, so what the heck is it doing here, deep in the heart of N&W
territory?

Later, I ran across this image:
http://www.railpictures.net/viewphoto.php?id=322030&nseq=28 with a somewhat
similar looking signal and the description mentions it as being an automatic
switch signal. I didn't recognize the term automatic switch, but wondered
if it was the same thing as a spring switch, so I Googled “spring switch
signal” and was led to a copy of the law (code of federal regulation) that
established the requirements for signal protection of spring switch
installations (oh yes there is). Just for grins, I have included the
wording below because it brought such clarity to the situation :^)

Hope you guys are able do a little better job of clearing things up.

Jim Cochran


 § 236.14 Spring switch signal protection; requirements.

*(a)* The indication of signal governing movements from siding to main
track with the current of traffic on track signaled for movements in only
one direction through a spring switch in automatic block signal territory
shall be not less restrictive than “Proceed at Restricted Speed' when the
block, into which movements are governed by the signal, is occupied, and
shall be “Stop” when the main track is occupied by a train approaching the
switch within at least 1,500 feet in approach of the approach signal
located stopping distance from the main track signal governing trailing
movements over switch, except that the indication may be caused to be less
restrictive if approach or time locking is used.

*(b)* The indication of signal governing movements against the current of
traffic from the reverse main of main tracks to a single track, or signal
governing movements from a siding to a main track signaled for movements in
either direction, through a spring switch, in automatic block signal
territory, shall be not less restrictive than “Proceed at Restricted Speed”
when the block, into which movements are governed by the signal, is
occupied by a preceding train, and shall be “Stop” when the block on the
single track into which the signal governs is occupied by an opposing train.

*(c)* The indication of signal governing movements against the current of
traffic from the reverse main of main tracks to a single track or signal
governing movements from a siding to a main track signaled for movements in
either direction through a spring switch in automatic block signal
territory shall be “Stop” when the normal direction main track of the
double track or the single track signaled for movements in both directions
is occupied by a train approaching the switch within at least 1,500 feet in
approach of the approach signal located stopping distance from the main
track signal governing trailing movements over switch, except that
indication may be caused to be less restrictive if approach or time locking
is used.
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