Signal aspects

[NW Modeling List]

Ron,
  I presented the same question at work a while back and here's what they told me, and it makes sense.  
   
  A Diverging Approach is telling you to proceed through the turnout prepared to stop at the next signal.  Basically, telling the train crew that the signal beyond that one is giving a Stop indication.
   
  If that same signal beyond the Diverging Approach signal were to upgrade to an Approach or Clear, then the Diverging Approach would upgrade to a Diverging Clear, meaning they don't have to be prepared to stop at the next signal.  You cannot give a Diverging Clear with a Stop signal beyond it.  That would be a "False Proceed" signal, and is not good!
   
  However, a Restricting is telling the train crew to proceed through the switch at restricted speed.  Many times this is used if a train is going into a yard track.  Quite often it means the train is leaving signalled territory, as it would on a branch line.  You can't give a Clear or Approach on a signal if it is the last signal a crew will encounter, as both aspects are giving you an indication leading to another signal.  A Restricting doesn't necessarially do this.
   
  Ben Blevins
   

NW Modeling List <nw-modeling-list at nwhs.org> wrote:
  What is the difference between "Restricting" and "Diverging 
Approach"? I've got a good idea of "Diverging Approach", but what is 
"Restricting"?

Ron Davis

At 03:50 PM 1/17/2008, you wrote:

>Ted,

> Here's a diagram of what the aspects are, both in position signal 

> and CPL signal diagrams. Now, the aspects were changed around 1952 

> and this change eliminated the horizontal aspects on the B arm of 

> the signals, and the marker lights underneath a B or C arm if the 

> signal was so equipped were also eliminated. This marker was 

> replaced by a letter plate "S". This is something Uncle EdK 

> explained to me a great many years ago.

>

> Now, the aspects as I have them named: They weren't known by a 

> "name" so to speak in the Position Signal era as far as I know, but 

> now the color aspects are named as I have them listed. The 

> indications are quite lengthy, so I left them out. I hope this helps.

>

> Oh, and the number plates were removed in the 60's or 

> 70's. These signals now have names as per the Southern practice.

>

> Ben Blevins

>

>[moderator]Image at following url:

>http://nwhs.org/qna/photos/20080117_BracketAspects.jpg



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