HI Folks: First Off, I am posting similar messages on several of the sub forums in The Ready Track, if this is wrong, please accept my apologies. Im planning a model railroad based loosely on the San Luis and Rio Grande. I am looking for information about the signaling protocols used in the area, in this case, specifically the BNSF. I realize that in-cab signaling and PTC are to some degree replacing external signal lights, but for my layout, I would like external signals, but what I am having a difficult time finding information about is the different signal aspects and their meanings. Does anyone have this information and / or some links? Thanks TIM San Luis and Rio Grande
Tim, A quick Google search comes up with lots of different reference materials for all the railroads you have posted your question for. One site, which has collected them in a nice format: http://signals.jovet.net/rules/
Hey Rick: Figures, I didnt find that site -- looks like good stuff -- thanks a bunch TIM San Luis and Rio Grande
PTC on the Class 1's is being installed as a overlay application upon the existing Automatic Block Signal Systems. Most carriers, on the routes that require PTC, are using PTC as an excuse to renew and relocate signals in the field to state of the art equipment and thus replacing some equipment that has been in the field since before WW II.
I'm supposing that there have been enormous nationwide changes in signal applications in pursuit of PTC. I made it my mission to capture photos of the historic stuff before it was replaced, such as this classic ACL signal bridge on the main at Lanes, SC taken in October 2014. PTC signals were at the ready, turned field side.
Although it has resulted in a national homogenization of appearance and in the case of my local CSX line, a number of signals were added in locations that didn't have signals before. As a signal fan, I'm saddened at seeing the old signals removed. Used to be that you could see a signal in unfamiliar territory and make an accurate guess as to who owned the line.
PTC isn't the real reason that's happening. It's mostly happening, because 1, the signal structures are aging and 2, it's cheaper to go with a uniformed standard for these structures.
The signals in the field are ok for PTC, some of the stuff in the cabinets needs to be updated, so a lot of signals are being updated too, signal spacing, etc. Its not required by PTC but PTC is the motivation to change the signals.
This is all wrong. Searchlight signaling is not compatible with solid-state PTC systems. With searchlights, the searchlight mechanisms themselves are part of the signaling relay circuits. The physical position of the roundels affects the signal aspects in advance. It just isn't really practical to try to overlay solid-state electronics on top of that. This is why all searchlights are being converted to colorlights in PTC territory.
Virtually anything CAN be done - how much do you want to spend to do it. Systems COULD have been designed to make PTC compatible with searchlight signals - at what cost is the question. Carriers looked at the equation from the perspective that the already installed signals had been in place for 30 - 40 - 50 or more years and were getting increasingly hard and expensive to maintain. With the PTC requirements it was cheaper and easier to 'scrap' the old systems and install new hardware at spacings appropriate to modern train lengths. Money, Money, Money is the answer.