Western Railroad Discussion > Signal Lights

Are Signal lights controlled by the local dispatcher or from Omaha in the case of UP and
Forth Worth in the case of BNSF?

It depends on the territory. In the case of the UP, some are controlled by the dispatcher in Omaha while others are controlled by the UP dispatcher in San Bernardino. I believe there is even one in the Roseville area and maybe other areas around the country as well.

JDE

It's my understanding that UP lines leading into Houston are dispatched from a center jointly run by UP and BNSF that sits in (as I recall) Spring, Texas (near Houston), and that UP trains on the Southern Powder River Basin Joint Line are dispatched by UP dispatching personnal located at the BNSF system dispatching center at Ft. Worth, TX. The UP Southern California lines are dispatched from the BNSF regional center in (I think) San Bernardino. Everything else on the UP system is run from Omaha. Dispatching mavens will correct any errors I've made here, But I think the above is pretty accurate.
--billio

And, of course, not all signals are "controlled" by the dispatcher. Intermediates operate automatically, and there may be automatic interlockers on the UP (most likely at remote diamonds on branches and/or drawbridges). I can't cite any examples of the latter, but just raising the possibility.

If you take it really serious, the only light a Dispatcher controls is the red (stop) indication at interlockings. any thing better than stop is controlled by route and the track occupancy.
Therefor in every rulebook it states a Dispatcher can not give the signal indication to crew by radio or telephone, he can only give you the OK by signal or fact that he gave you a route.
with Automatic signals the same applies only the red indication is controlled by track and occupancy, not the dispatcher.

What you're saying is that a dispatcher controls signals at a control point with the exception of an automatic interlocking. ABS signals, or intermediate signals as some call them, work in conjunction with the "A" or absolute signals.

JDE

Steamjocky Wrote:
-------------------------------------------------------
> What you're saying is that a dispatcher controls
> signals at a control point with the exception of
> an automatic interlocking. ABS signals, or
> intermediate signals as some call them, work in
> conjunction with the "A" or absolute signals.
>
> JDE

That's right. I just wanted to make it clear to the person making the original inquiry, that even in CTC, the dispatchers "control" a relatively low percentage of signals. I thought this should be made clear since the question hinted, at least to me, at low familiarity with how signal systems work.

And you did. I just tried to clear it up a little bit more. Hope you didn't mind.

JDE

The dispatcher or control operator cannot directly control any signals.

All US signals are controlled by what is called field logic. Computer-like logic circuits at the location of each signal will display the most favorable aspect of the signal at a particular location based upon information fed to it from track circuits, switch position detectors, slide fences, etc., and requests from the control operator.

A dispatcher or control operator may only request a control point in the field to turn a switch or approve a route through a specific section of track, and the local "switch shanty" will act upon that request _IF_ it decides such a move will not violate rules established at that control point.