The interlocking is located on what is today the Norfolk Southern Reading Line, which was previously operated by Conrail and ultimately the Reading Company/ The line runs between the former industrial centers of Allentown, PA and Reading PA. The line is only about 30 miles long and the majority of double track line is still signaled as Rule 251, single direction ABS. CP-ALBURTIS is both a basic crossover and junction with the C&F secondary, which used to run to a connection with the Lehigh Valley RR main line, but today just serves a number of local industries to a point a few miles short of where the LVRR main used to be. Back in Reading days I would assume that the junction would have been a typical ABS territory affair with no interlocking whatsoever and electrocally locked, hand operated crossovers and turnouts although it might have always had some sort of interlocking station. At some point in the late Reading period the interlocking was placed under remote control as the Reading was a pretty heavy user of CTC compared with riven PRR which continued to believe in manned block and interlocking stations.
Anyway, at this point I am just going to dive into the photos. I'll start with the 2002 set and then show how things had changed by 2008. For reverence you can check out the 1997 Conrail Reading Line employee timetables here, specifically page 1.
We begin by seeing the 346L eastbound home signal mast on #2 track. This signal was a Conrail replacement for whatever Reading era signals had been installed when the interlocking was put under remote control. These would have probably been target type color light signals with the round backing and triangular configuration. Back in the 1980's Conrail standardized on the Michigan Central style small target GRS model SA searchlight signal (before itself shifting to target type color lights) and this mast signal is an example of that. The 1980's date can be determined by the spiral corrugated steel foundation and non-solid base of the mast. According to the interlocking chart, this signal can also display R/Y/R Medium Approach for movements into the C&F branch as well as R/R/Y. That makes me assume there was an "End Auto Block" sign somewhere down the C&F.
If you notice the signal was displaying a Clear aspect for an approaching train of roadrailers, which drop the signal to stop after it passes.
Looking at the signal straight on we can see the improved light intensity as well as the small 344L reverse direction dwarf signals to the right of track #1. You can also get a hint that some changes are about to take place.
Moving to the other end of the interlocking we find a first generation relay hut that indicates that the current interlocking was installed sometime during the Reading era. The concrete construction dates the hut from the time before the new pre-fab metal huts became commonplace in the 1970's. We also see on the 344R signal the same small target searchlights on an older type of mast with a solid base. As the Reading did not install these types of searchlight I have to assume they were a Conrail upgrade despite the rust, but the mast may be original as Conrail was known to re-use the existing Reading masts.
Also of note is the Reading Safety District billboard, propane tanks for the point heaters and an electric power connection to the commercial grid.
Observing the mast and relay hut head on we see that there is a grade crossing outside of interlocking limits on track #1, but inside the limits on track #2. The reverse direction 346R dwarf signal (not pictured) was placed slightly east of the crossing to save on an extra insulated rail joint so when the train exits the interlocking it also ceases to occupy the crossing circuit. More evidence of upcoming change is in the foreground.
Closer view of that westbound track #1 344R mast signal. The searchlights are not evenly spaced, but we can see that the targets are less rusty than the mast indicating they were Conrail era replacements. In this view the safety sign is legible.
The C&F secondary track crosses the road just a few feet north of the Main Line. It is still protected by the same grade crossing gates. In this view we can see the shiny rails contrasting with the lush green carpet of weeds. The relay hut is sandwiched between the C&F and the main tracks and behind the relay hut is a slew of battery cases which probably served as backup to the mains power.
Movements off the C&F were governed by the 342R twin stack SA dwarf signal backed up by an adorable little shrubbery. The double stack signal allowed for G/R and Y/R slow speed aspects as well as a R/Y Restricting aspect.
Zooming in close we can see the anti-phantom aspect angled filters in front of the Fresnel lenses on the SA dwarf stack. Also note the paper wasp nest. Almost every signal I have seen has a wasp nest hidden somewhere about it. Yes there is a wasp on it.
Side view of the dwarf stack.
And a rear view showing off the weed covered track.
The operational issues of blasting out onto the main line stem from the use of a hand operated split point derail and main line turnout. That's right, once your train pulled out of the branch line someone would have to stay behind, re-align the points and lock them and then walk back to the front of the train. The split point derail IS provided with a direct burner style automatic point heater and a GRS model of electric lock.
Here we see the level 347 main line electric lock and hand operated points. On ABS track the procedure for use was to open the flat door and depress a handle thing that would either unlock the points or trigger a timer to run. Because this is within interlocking limits this lock is directly controlled by the dispatcher based on interlocking and track occupancy logic. Anyway the electric lock works into a slot on the lock bar much in the same fashion as an Annet's Key FPL. This page gives a general idea of what these sorts of electric locks look like inside.
Here we have a somewhat wider view of the interlocking showing the power operated main line crossover and the hand operated C&F secondary points.
The electric point machines on the power crossovers are US&S M-3 series. I am unsure as if they are originals or not as the old circuit controller box most certainly is, but the M-3 itself may be a slightly newer Conrail replacement. In the foreground we see the arm thick bundles of individual wires that run from the relay hut to the rest of the interlocking.
Here we see the 343 crossover which is either Medium or Slow speed. The point heaters are of the Conrail shrouded type and to the left of the pic you can again see those thick bundles of pole line cables running the length of the interlocking. This also gives an idea of how short the interlocking limits are.
It was good that I got out there when I did because it was clear that CP-ALBURTIS had been targeted for a rebuild. Here we see to to-be installed sets of points stacked up.
A new style stainless steel relay hut that doesn't even need a solid foundation.
New dwarf signals and spools of signal cable.
New GRS model 5H point machines.
And new turnouts that have already been installed. Note the point detection unit that was installed temporarily to ensure that the points don't happen to split.
While not part of the interlocking proper, about 1100 feet down the C&F Secondary was a distant signal that provided warning of the approaching absolute signal at CP-ALBURTIS. Often times this sort of signal will be a fixed distant displaying NORAC Rule 293c, Approach Restricting, but in this case the signal can also display NORAC Rule 293b, Approach Clear. While neither signal conveys block information, they indicate the state of the absolute signal at the interlocking. Approach Restricting indicates that the home signal will be at stop and Approach Clear indicates it will be displaying some favorable proceed aspect. Each rule is displayed by a single lamp, yellow and green, over a fixed (A) plate, which in this case is visible just below the two lamp signal head.
This signal is placed about 1200 feet from the home signal which is a rather short distance for this sort of thing, but is understandable given the slow speed of the C&F secondary. The signal also used to protect a small yard that was located off the C&F track between there and the interlocking. An Approach Clear could confirm that all yard switches were properly aligned between there and the home signal, further reducing possible delays. Anyway the new distant signal is located on the ground by the existing one, but it would end up being placed a further 700 feet away from the interlocking around the bend where trains can better sight it.
The mast was displaying an Approach aspect implying that I had just missed a train or there was a track circuit failure one block ahead. No wasted signal lamps here. There are only two heads and the bottom one can only display the Restricting yellow and a second Red. When trains takes a diverging route here, either to enter the C&F or to wrong rail on the Reading Line they must get a Form D movement authority. The Restricting signal telsl the engineer that he is entering non-track circuited territory and can't give him any better indication because for all the interlocking knows there could be dragons out there. Trains can increase speed once it enters the DCS territory with the proper movement authority.
The three lamp modular dwarf stack also uses Safetran hardware and is in the configuration Y/G/R. These signals can display multiple lamps at once to cover the Medium Speed aspects without using a second group of modules. For example I have see signals like this display Y/*R* and Y/*G* at other interlockings
Side view of both the eastbound signals showing the improved maintainer safety appliances.
The new turnouts are clearly #15's good for 30mph, which is more than the old turnouts which I suspect were only good for 15. Here we see the facing turnout that is also used by trains on track #2 to access the C&F secondary.
The point heaters have been changed from direct burner to the forced air variety. They still make use of propane for energy drawn from a new set of on-site tanks.
More point heaters showing their little chimneys all in a straight line. To the left is a siding track that continues to the west for a few thousand feed before tying back into the main line at a hand operated switch. This track was absent in 2002 due to the rebuilding efforts and was not brand new upgrade.
The siding track get this little two position dwarf as it has no route that can lead to anything except DCS territory. There is no yellow disc working here. All movements through any worked points must be protected by absolute signals.
Here we see a closeup of the points on the C&F crossover showing the ductwork that directs the heated forced air around the blades to melt any ice and snow. Because this is now a crossover instead of a single turnout there is no need for a derail as trains can be routed down the siding track.
Rear of the C&F 3-module dwarf showing a most efficient locking device.
Front of the same. All three of the 3 module dwarfs can display Stop (R), Restricting (Y), Medium Clear (G/*R*) and Medium Approach (Y/*R*).
Another small positive outcome of the re-signaling was the application of a Conrail style nameplate to the new relay hut. The old CP-ALBURTIS did not come with a ID-plate for some reason.
Wow, that's a LOT of propane.
Although not out of use the old school tar impregnated cloth wrapped cable bundles were still hanging up on the poles. WTF did they need all those wires for in the first place!!
The new westbound signals are a mirror image of the eastbound ones. Compared to the 2002 arrangement the track #1 mast signal has moved east to capture the grade crossing completely within interlocking limits. Also the mast, relay hut, battery boxes, propane tanks and safety sign of the old interlocking have been completely bulldozed.
I was lucky enough to catch the westbound mast displaying a Clear indication.
Close up view of the heads displaying the Clear indication.
Closeup of the opposite direction dwarf signal.
Rear quarter view of the westbound home signals.
I will finish with this photo of the restaurant adjacent to the grade crossing and interlocking. The appropriate name convinced me to pop in for lunch, but the food was nothing to really write home about. If you ever find yourself in Alburtis don't be taken in by its pandering to rail enthusiasts.