"New" CPLs at Roanoke (nw-mailing-list@nwhs.org)

nw-mailing-list at nwhs.org nw-mailing-list at nwhs.org
Mon Apr 18 15:05:12 EDT 2005

OK, you guys got my curiosity up so I talked to the guy who handled the job.

Here's the skinny:

The signals in question are home signals for one of the largest interlocking
plants on the old N&W.  In order to convert to colorlight signals, it would
have required a good bit of re-wiring.  Anytime you make wiring changes (the
FRA calls it "disarrangement") extensive testing is required before putting
the plant back in service.  By re-furbishing some CPL's and just re-cabling
to feed them, you only have to verify the aspects are what they are supposed
to be.  So it was a cost saving decision; saved time and labor.  

This is also apparent on some of the poleline elimination work on such as
the Bristol and Shenandoah lines, where intermediate signals are mostly
changed, but control point signals remain CPL's, I believe.

John Marbury
retired NS, C&S 

In discussing the CPLs a few years back with an NS Official in the 
Signal and Communication department, I asked about a specific control 
point signal near my house, this is a single mast, 2 head signal. He 
knew exactly which one I was referring to and said it was not slated 
for replacement due to its complexity of the various aspects, he 
further stated that unless there is a major failure on any of that 
type, they were not to be replaced. Again, this was a few years back, 
but makes the most sense for this specific location.

Ken Miller
On Apr 16, 2005, at 9:25 PM, nw-mailing-list at nwhs.org wrote:

> Not sure as to why they are there, but I worked under the new signal 
> last week, and the only explanation that I can come up with is that 
> the placement of the signals is in the direct eastern throat of the 
> yard, complicated by the fact that four main lines converge at this 
> point( 1 Shenandoah, 2 Norfolk & 1 Winston-Salem), and the aspects 
> would be easier read and simpler to explain by the older types of 
> cpls, rather than a gaggle of the newer stoplight formations. Just a 
> thought....
> Gary Price

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