Restricting

[NW Mailing List]

Restricting was widely used on the Pocahontas Division in several ways and
on fixed-aspect, automatic and control signals:

On automatic signals only upgrade for close following movements and
(apparently) on grades of 1 percent or greater (e.g., Elkhorn Grade, Huger
Hill).  One exception is upgrade EB into Elkhorn Tunnel which displays a
Stop and Stay (also, WB at the other portal) to allow one movement at a
time per track in the tunnel.

On a fixed-aspect signal at the end of signaled territory (Radford pull-in,
Giatto Wye, Wilcoe).

On a control signal lined for the left main when signaled only in the
opposite direction.

On a control signal lined for a diverging route at restricted speed and to
help distinguish a second diverging route.  The diverging indications might
be reserved for just a crossover route between mains (Bluestone WB, Burke).

On a control signal as a "call on" signal to allow movement into an
occupied block.  The dispatcher could override a Stop and Stay with a
button that changed the aspect to Restricting.  This was available at
interlockings where pushers would get on (west end of Farm, Sandy Huff).

Grant Carpenter


> Date: Wed, 18 Sep 2013

> Subject: Re: N&W signal route diagrams

>

>Now then, Ben points out that you could accomplish

> what I was asking about (allowing a following movement to continue without

> stopping) by providing a restricting aspect.  This was done on grades to

> prevent the need to restart heavy trains, I believe.  Were there instances

> of interlockings that could display the restricting aspect?  I believe Ben

> indicated that in the majority of instances this was not the case.  My

> assumption would be that it was felt that the delay was not significant

> enough to warrant the expense of the additional aspect and associated

> circuitry.  Any other insights/conjecture?

> Thanks again,

> Jim Cochran