Search This Blog

Monday, May 30, 2011

CP-ALBURTIS: Then and Now

In an effort to keep my loyal readers from losing interests today I will reach into the storage bin for a bit of an historical piece. Back before I had unlimited free web hosting I was somewhat limited by the number and size of photos I could post online. One result was that many of my early photo sets were never uploaded in their entirety so as I clean up my archives I will occasionally re-process the photos and upload them. The latest result of this heritage project were some photos I took in 2002 of CP-ALBURTIS in Alburtis, PA.

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 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. The three lights are somewhat redundant as all diverging routes lead to non-signaled territory so all that would have been needed is R/Y Restricting. I assume that the signals were assuming that at some point the line would be converted to CTC and the lower head would be needed to display slow speed aspects (R/R/G and R/R/*Y*) for regular crossover moves.

If you notice the signal was displaying a Clear aspect for an approaching train of road railers.

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 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 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 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 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 this twin stack SA dwarf signal backed up by an adorable little shrubbery. The double stack signal indicates that the C&F connection to the main was good for 30mph Medium Speed moves...although as you will see there are operational issues to jetting out onto the main at a high rate of speed.

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 main line electric lock and hand operated points. 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 probably 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 power junction 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 crossovers which are 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 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.

So let us now move ahead 6 years and see how CP-ALBURTIS has changed. Starting off at the west end we see that the re-signaling of CP-ALBURTIS was not part of any larger project to CTC the line. Furthermore the new high signals pre-date NS's full embrace of the Darth Vader style color light, so thank god for small miracles. Here we can see the new traffic light style eastbound track #2 mast signal next to the reverse direction modular dwarf to the right of track #1.

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.


  1. I know it's over 3 years since you posted this, but thought I'd correct some of your assumptions. I have the track/signal diagrams for every interlocking on the Reading as of 1976 (courtesy of Conrail) and most hadn't changed in years. Except for the removal of some siding trackage, Alburtis as you saw it in 2002 was essentially as it was going back to 1963, at which time the switches were electrified and the control transferred to Oley Tower. The original Reading signals were indeed searchlights. In your photos the heads do look better than the mast, but if they were changed by Conrail, I couldn't tell you why. And offhand I'm not aware of any location where Conrail replaced Type G with SL. Reading made extensive use of searchlights on the East Penn Branch and they date at this interlocking from 1946. While the Type G were dominant system-wide (often including the horizontal two-light heads), SLs were indeed used at various locations with both small and large targets.

    Also, on the Reading, from what I can see on these diagrams, all crossovers were considered interlockings and eventually remote controlled. You're right that the Reading was a heavy (and early) user of CTC and they began remote controlling back in the early 60s. Many of the towers I used to see in the early 70s were long out of use (unbeknownst to me at the time).

    Love your photos and your postings.

    1. The small target New York Central style searchlights were a Conrail trademark. The eastbound SL mast is clearly a 1980's install given the mast design and base. The westbound mast might be original with SL's replacing the target signals.

      I have since found the same interlocking diagram you make reference to. Perhaps I'll update the post.

  2. First, absolutely love these 44 photos! I'd like to add some additional info for some of these pictures. I am the Sales Manager for SERRMI Products, Inc. of Atlanta, Georgia. I am going to identify our products in some of these pictures. Starting with the photo at the top of the page as photo 1, count down to photo 20.

    The Instrument House in photo 20 is actually Aluminum Alloy 3003-H14 structural grade wall, door, and roof panels and the structural frame members you can't see are made of Aluminum Alloy 6061-T6. On each of the 4 corners are a SERRMI patented "Pipe Style Drop Down Pier". Holes are dug in the ground to predetermined depths by the installation contractors or railroad crews.The aluminum shrouds cover the mechanism that is utilized to "level" the House and final grading is completed. Pictures 35 & 36 with the "ALBURTIS" sign are also made from the same materials. These SERRMI style of Aluminum Instrument Houses are circa 1990's style and were adapted from our previous 1980's Instrument Houses made of steel....moving to structural aluminum was a move promoted by SERRMI and became more popular as the 1990's continued and now a very popular material specified by most Class I "Freight Railroads". These aforementioned pictured Houses roof style were changed by SERRMI at the end of the 1990s. We are rebuilding our web page, but you can simply type in your Browser's Search Line; Serrmi Products, Inc., scroll all the way to the bottom and to the left you will be able to download our PDF. file SERRMI 2016 Catalog. See pages 2-10 for pictures and the 3 styles of Piers.

    Pictures 21 and 34 - The 3 "stackable" signal heads of the Dwarf Signal, are atop of SERRMI's galvanized steel and cast aluminum terminal box assembly that acts as the mounting or the signal heads, the foundation that is placed into the ground, allows the signal cable to be drawn up the foundation and wired or "terminated" inside the cast aluminum terminal box onto terminals SERRMI places inside the cast aluminum box...the Railroads specify whose signal heads, how many, and the number of terminals. Picture 21 shows the assembly before burial and 34 is a typical finished installation....on Page 22 of the SERRMI Catalog 2016 you will see more info.

    Pictures 25,26,28,39, 40-43 - Are SERRMI's High Color Light Wayside Signals. Various types of signal well as the signal heads with "Darth Vader" hoods....may be mounted atop the signal brackets. These are SERRMI Catalog # 40395 Wayside Signals, 2 Units High, Single Direction. See pages 11-15 of the SERRMI Catalog 2016.

    Many thanks for all your hard work to preserve the history of railroading.
    Dave Quail
    Sales Manager
    SERRMI Products, Inc.
    5290 Tulane Dr., S.W.
    Atlanta, GA 30336

    1. Wow, this is the most interesting "spam" comment I have ever gotten XD Thank you so much for posting!

      BTW I'm personally a big fan of CorTen, but I guess the manufacturing processes has made Aluminum more cost competitive since the 1980's.

    2. Cor-Ten was first introduced by United States Steel in the early 1930's and US Steel touted Cor-Ten as "Weathering Steel". US Steel targeted specifically the fabricators of coal cars for the Railroad Industry. US Steel continued to refine the process into the 1960's and eventually it found its way into the fabrication of railroad wayside instrument houses/bungalows/huts and instrument case enclosures as well.

      A simple explanation of how Cor-Ten works is by the "bleed" or "blooming" of an oxidizing process of a yellowish, rust colored appearance that exudes to the surface and this layer was intentionally designed by US Steel to dramatically slow the process of corrosion and rusting. Although it may be prepared for and painted...the classic aluminum paint on steel as one example....CONRAIL is the only railroad I'm aware of who used Cor-Ten by the way it was intended to be used; with no paint.

      Under your "Amtrak Label" with 49 pictures...if you scroll way down to where your following description starts with..."I didn't know what this was at the time, but I later yearned this rather large relay-hut looking thing was actually the southern supply point for the 6kv 100hz signal power line running from here to Enola"...this is a PERFECT example of a Cor-Ten House/Hut.

      So when people see these Huts they are inclined to think they are rusting hulks...truly they will rust away some day...but it will be a long, long time before that happens.

      To my knowledge, back at the height of CONRAIL, SERRMI never painted any Cor-Ten structure it fabricated for CONRAIL. CONRAIL's people understood and embraced Cor-Ten for its merits and was used as it was truly intended..."Weathering Steel".

      Dave Quail
      SERRMI Products, Inc.

    3. What happened with Cor-Ten at a lot of railroads is the inability of Cor-Ten to resist salt water in air environments, proximity to roads where salt is used for winter treatment, proximity to chemical plants where certain chemical byproducts are released ....and when in the Fall, if large concentrations of leaves(when wet) accumulated on areas of these Wayside Cor-Ten enclosures...all of these aforementioned conditions interfere with the ability of the "Weathering Steel" oxidation process to perform reliably. Whereas, these are not a concern at all for structural aluminum alloys.

      However, steels are still used and especially popular on Transit Railways here in the U.S., and in both Transit and Freight Railroads in Mexico, Canada, and Central & South America and all of it is painted and if the Wayside enclosures are going to see the effects of the aforementioned; special paints and/or top coatings are used to protect from corrosion and rusting.

      Dave Quail
      SERRMI Products, Inc.