Train Control, Signaling, and Switch Heaters
Page 2Completion of this project made the Feather River Canyon single track line equal to approximately 65% of the train operation capacity of a similar distance of double track. This improvement and removal of what had at times under wartime conditions been an operating "bottleneck" increased the capacity of the entire line and made the canyon the most fluid operation on the road with the exception of the 183 mile double track district in eastern Nevada.
This improvement by WP was in line with improvements being made by other American railroads in their endeavors to assure that wartime materials and personnel shall be handled promptly to avoid delay in production or prosecution of the war.
In order that all dispatchers be centrally located at division headquarters the Keddie control machine was relocated to Sacramento, California on July 6, 1947 when installation work began on the First Subdivision between Oakland and Stockton. Movement of the machine was accomplished with a stoppage of only 12 hours and 29 minutes in the operation of the board. The move was made by special train. A difference between this installation and that in the canyon was that upon a “take siding” signal indication the trainman had to hand throw the turnout to line the switch. Placed in service March 1948 two of the three control machines were now manned 24 hours a day. Construction was started immediately on the installation of CTC between Stockton and Oroville, which would completely bring the division under centralized signaling control with all dispatchers of the Western Division under one roof at the Sacramento Division Headquarters.
On the original Feather River Canyon installation the traffic control system machine indications were located as follows: Track occupancy indications, power-off indications and traffic direction indications only were located on the track etching. The switch indications and signal indications were located immediately adjacent to the lever controlling the individual function.
The new control machine for the Oakland-Stockton installation was modified so that all indication lamps were normally dark in order to provide greater ease in interpretation of the control panel. All signal indications were located on the track model immediately adjacent to the switch involved. The only indications on the control portion of the panel were the out-of-correspondence lights for the switch and signal levers. These out-of-correspondence lights were illuminated whenever the lever or the machine did not correspond with the function in the field. This installation was likewise controlled by coded track facilities and the sidings were not signaled.
The final section of the Oakland-Stockton installation was placed in service in July, 1948. Immediately thereafter construction was inaugurated on the Second Subdivision of the Western Division, Stockton to Oroville. This section would complete the signal installation on the Western Division insofar as operation by signal indication was concerned; that is, the entire main line of the Western Division would then be controlled by CTC.
|One of the CTC panels at Sacramento.|
The entire Western Division was controlled through the medium of two code control wires which extend from Oakland to Portola (314 miles). The large number of indications and controls required for this extensive territory was handled over this one pair of wires through the medium of carrier circuits. This line is segregated into eight different sections through the medium of six carrier sections and two direct-current sections.
In addition to the CTC coded carrier equipment, there were also two duplex carrier telephone circuits and three separate physical circuits, on this one pair of wires. Two of the outlying physical sections were tied into the dispatcher's control board through the medium of the duplex carrier equipment.
The train graph for the original installation indicated the occupancy of the detector circuit only. The latter two installations were equipped with polarized train graph pins in order that the occupancy of the detector circuit as well as the clearing of the signal could be recorded on the train graph.
All cases and houses which contained equipment for use in the field on the Western Division installation were wired by the Union Switch and Signal Company at Swissvale, Pennsylvania.
When the company made the decision to extend this type of control eastward from Portola a problem confronting the installation project was the cold hard winters experienced in the northern Nevada and Utah regions. Work stoppages would be inevitable. Already under the control of the signal department it was decided that work during the summer months could be accomplished faster if the cases and control houses were wired and fitted out by the company in their own shops instead of being contracted out.
Desiring all work be performed in a central location arrangements were quickly made for a portion of the property at the Sacramento shops be dedicated for this use. Construction of a Quonset-type shop building, warehouse, storage area, and loading dock were soon complete. Previously located in Livermore the concrete products yard was also moved to Sacramento. Now in one location all aspects of signal and control house construction, repair, and maintenance would be accomplished in one location.
The 6 by 8 ft control houses were shipped from the signal company factory at Pittsburgh, Pennsylvania in a knocked-down packaged unit, thereby, reducing freight cost on the long haul from Pittsburgh to Sacramento. The houses were then erected and painted by forces at Sacramento.
Working from plans designed by the signal engineers staff in San Francisco the Sacramento “wire gang” pre-wired control houses, signal boxes, and rebuilt seventy-one Style “B” semaphores into searchlight signals for use with the new system. Concrete pads and footing were poured by the cement plant and accompanied the signaling equipment into the field for use during installation. All routine repair and overhaul jobs of signal related equipment was also handled in Sacramento making the results of the decision to centrally locate the signal department maintenance staff a sound one.
Continuing eastward the 50-mile section of rail between Portola and Herlong came under CTC control on June 16, 1950. Control of 366 miles of railroad right of way between Oakland and Herlong, California was now under the direct control of dispatchers with work continuing to bring all train movement under the CTC system by 1953. During installation in the Eastern Division certain sidings were lengthened to permit handling of 125 car trains in an effort to enhance and speed operations.
The CTC system from Portola east incorporated the same basic circuit design as that used on the Western Division, that is, reversible coded track circuits were used throughout the installation. The sidings on the installation east from Portola were not initially signaled.
The control machine for the Portola-Winnemucca territory (a distance of 215 miles) was controlled from Elko, Nevada, 129 miles east of the most easterly control point in this section (Weso). This territory was likewise controlled by one pair of code wires. In view of the long line, the large number of control stations in this section were controlled through the medium of three coded carrier sections and one direct-current coded section. The direct-current coded section was used to control the carrier repeaters between Elko and the first control station (Weso). In view of the large amount of carrier equipment involved on this installation, the extreme left-hand panel of the control machine was devoted to telephone control equipment and carrier control equipment. This line was likewise equipped with a duplex carrier telephone circuit due to the long distance involved. The duplex carrier equipment operated between Elko and Weso and thereby ties the physical circuit Weso to Portola to Elko. The physical circuit from Elko to Weso was tied into the Weso-Portola circuit through local circuits at Elko, thereby, creating in effect, one telephone circuit on the code pair, with the minimum of attenuation due to the physical line.
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