Signal in dark territory.

I was wondering if anyone knew what this signal would be used for. It is located on the CSX St. Lawrence Sub between Evans Mills and Philadelphia, NY, which is dark territory. It lights up when the head end passes than goes dark once the entire train has passed for a train in either direction. To the best of my knowledge this is the only signal on the line other than the ones further south in Syracuse.
http://www.rrpicturearchives.net/showPi ... ?id=538808

I'm not familiar with the territory, but could this be a distant signal for an upcoming interlocking?

If you look under the signal head it has a sign DS.
Distance signal , it only tells crews they are not to exceed 30 mph aproaching signalled territory. The signal does not convey track info..

DRN got it half right. It IS a Distant Signal, and it doesn't convey track occupancy. It only conveys, whether a train approaching the following signal, or interlocking, may proceed, at a speed specified in the TTSI, or must be prepared to stop. The STOPPING portion, probably slightly more important, than any speeds guessed.

xjqcf wrote:Was this line ex-Conrail formerly operated under NORAC? If so it might be displaying rule 293a, Switch Open Signal : "Proceed prepared to stop short of open switches" This along with companion rule 293 Switch Closed Signal appear to serve the same function as a traditional "Switch Indicator".

For the traditional "Distant Signal", NORAC has (or had; I'm referencing the 8th edition) Rules 293b and 293c, "Approach Clear" and "Approach Restricting" which have an "A" plate attached. The respective indications include the following NOTE: "Does not convey block or track information"

Nope. See the picture. It is CLEARLY a Distant Signal, with a very visible DS plate, directly under the head, on the mast. No track occupancy conditions conveyed, only indication, of how to proceed, upon the next signal.

Could it also be a Grade Signal, aren't they independant of Block signals?

Nope. A grade signal would have to be on an "Automatic", with a numberplate. There would also have to be a "G" plate, conforming with the rules, on your railroad. It says "DS" on it, therefor, it is a Distant Signal

Also note, the signal head displays only two colors, with an "Approach Distant Signal" indication being shown. An occupied block, showing approach, shows it's not a grade, or any type of automatic signal. The two colors shown, on the signal, are either yellow, or green. No other indication can be shown, other than proceed on next signal, or prepare to stop, on next signal. Regards

I would say that is a Switch Open Signal, because it is marked by a "DS" whereas most Distant Signal markers are only marked with a "D".

Switch Open Signal

Believe it, or not, the "switch open signal", is a variant of a distant signal. It conveys no indication, of block occupancy, it relays info how to proceed, upon the next signal. If the signal is a switch point indicator, or TTSI makes the next signal, a switch, you still have a Distant Signal".

There is indeed a spring switch on the south end of the siding, the north end switch is not a spring switch, there is also a crossover switch just before the south end of the wye for the Carthage Secondary. I can't recall ever seeing the signal display green, and regardless of train length or direction I've only seen it show yellow. This particular occasion the train didn't use the siding and so the switch was lined normal for the main.

PRR had a number of distant switch indicators on its Northern (Harrisburg-Buffalo/Erie and branches) Region up until the 1960's. The ones I remember resembled a vertically-aligned color-light signal, and some were connected to hand switches of relatively minor importance. The only rationale I can think of for their use would be to avoid coming upon a mis-aligned or sabotaged switch at speed, though a section crew working in the area could also use them as additional protection. I don't recall much mention of these devices in rulebooks or a reference like Rights of Trains, but the Pennsy listed them in Employees Timetables.

There is very little doubt that this is really a distant switch signal regardless of the technical name. There is a spring switch in the area and
if those spring switch points were not properly line up, the consequences
could be major.
Distant switch signals were very common not too many years ago, the
New Haven, Long Island and Pennsylvania-Reading Seashore Lines were
three among others that used them. The Long Island still uses them on
both the Montauk Branch east of Speonk and the main line to Greenport
east of Ronkonkoma.
The reason for only the yellow and green lights is because there is no
approach signal to a distant switch signal. They are not block signals and
are controlled by the position of switch points.
Noel Weaver

[quote="joha107"]I was wondering if anyone knew what this signal would be used for. It is located on the CSX St. Lawrence Sub between Evans Mills and Philadelphia, NY, which is dark territory. It lights up when the head end passes than goes dark once the entire train has passed for a train in either direction. To the best of my knowledge this is the only signal on the line other than the ones further south in Syracuse.
http://www.rrpicturearchives.net/showPi ... ?id=538808[/quot
These are similar to our Distant signals in Britain.I have two at my signalbox which come 'off' automatically when the associated stop signals are cleared.
There are some distants on the track circuit block system and these come 'off' when the signal ahead is showing a green aspect.
My system,Absolute Block,always has these type of signal.

That is a Rule 293 signal for a northbound trains indicating the position of the Spring Switch at PHIL for the siding at QM88.0.

The DS plate means it indicates switch position but does not convey block or track information. A clear aspect means proceed and an approach aspect means "proceed prepared to stop short of open switches".

It is an advance warning for the facing point Spring Switch. This is why there is a signal for northbound movements only. Southbound movements on either track would automatically trail through the switch.