Railroad Power Director Center - Thirtieth Street Station, Philadelphia Pennsylvania
Power Directors Circuit and Switch Indicating Boards were designed to visually and aurally indicate the operating status of the railroad's power system. This particular power director center monitored and supervised operation of all switches in the railroad's power control system from North Philadelphia to Wilmington, Delaware. The power directors working at this site oversaw and continually updated the electrical status of the system. Power directors were responsible for safely de-energizing catenary segments for maintenance and repair. Most commonly, actual physical control of a switch was accomplished by a tower or substation operator responding to telephoned orders from the power director. However, some power switching was done directly by the power director. The power director recorded the position of the switch by manually actuating a corresponding indicating light on the model board. The model board and operational system that evolved represents a precomputer technology for centralized control of a electrified railroad power network.
The early years of the 20th century saw the evolution of electrified railways all over the world. Electrical energy was and continues to be an effective, economical, clean and practical source of railroad traction power. Concurrent with the employment of electric power, railroad engineers developed methods of controlling and monitoring its distribution and use. For an electric railroad to work, controlled power had to be delivered to trackside in quantity. Supervision of power distribution and its regulation is the responsibility of workers designated as load dispatchers and power directors. These individuals are charged with the responsibility of overseeing the electrical equipment in the system under their control1. Power directors are responsible for coordinating power handling with train dispatchers and maintenance crews to safely allow work on the catenary and transmission system.
The development of computer-based control systems made earlier electrical relay control schemes obsolete and susceptible to replacement. In 1976 the Federal Railroad Administration, Amtrak and engineering consultants prepared a specification, which defined the elements for a computer-based control system for the Northeast Corridor. This system centralized train and electrification controls in one room. The new system is designated as the Centralized Electrification and Traffic Control System (CETC). With system reorganization the zone 7 Baltimore Power Director's Office was moved and consolidated with the Philadelphia office in April 1986. This merger was followed by merging Baltimore's zone 6 office in October 1987. Philadelphia's zone 5 followed shortly after that in December 1987. The last zone moved into CETC was zone 4 in May 1994.
Prior to activation of the new CETC system, traction power for the Amtrak trunk lines from North Philadelphia, Pennsylvania to Wilmington, Delaware was controlled and monitored from Philadelphia's Thirtieth Street Station. The control system was explicitly known as the Power Directors Circuit and Switch Indicating Board for zones 4 and 5. It was located in room No. 495 on the fourth floor of Amtrak's 30th Street Station in Philadelphia. The equipment shares room No. 495 with the Load Dispatcher's Office found immediately to its south. The section of the room devoted to Power Director's equipment was 35'-8" wide by 48'-0" long and contained approximately 1712 square feet. The model board itself is seven sided and partially open on the southeast side. The board would be eighty-six feet long had it been designed as a linear facility. It encompasses an area of about 860 square feet.
The model board, control and supervisory consoles exemplify a system used to monitor status of electrical power in the catenary, substations and other components of an electrified railroad. The system uses relay logic coupled with manual input to operate indicating lights on what is an electrical analog of the railroad's electrical system. The main function of the power director's office is to supervise all switching in the railroad power system for purposes of safety, operation and maintenance. The system is an example of precomputer technology used to control and monitor electric power.
Two operating switch consoles, a rotating carousel schematic board and a supervisory switch board are contained within the seven-sided periphery of the model board. An additional supervisory switch board and control panels are just outside the periphery of the model board and form part of its eastern boundary.
The board itself is made up of steel panels, measuring two feet square and 1/8" thick. The panels which face the operator exhibit a schematic representation of the railroad's electrical system corresponding to catenary and track layouts. The backs of the panels form a chassis for the indicating lights, cabling, relays, bells, buzzers and other operating components. A 10 foot high, steel angle iron framework supports the panels. Indicating lights are placed at locations on the schematic diagram of the system. These locations correspond to the actual positions of the breakers and switches they symbolize.
The model board indicating lights operate on 24 volts and the relays on 120 AC. Most wiring is typical of the 1930s, that is, stranded copper with varnished cambric insulation. The builders installed a fire alarm system for detecting fire in the wiring.
The Kellogg Switch Board Company of Chicago built the display board and switch consoles. Kellogg, no longer in operation, was a highly reputable firm and had supplied similar model boards to other railroads. Typically, Kellogg used standard telephone relays, indicating pilot light bulbs and conventional, readily available components in its custom-designed boards and consoles. Telephone parts had a proven record of reliability and were mass-produced to high quality standards by the Western Electric Company. The designers expected that they would be available as repair parts for the foreseeable future.
In 1928 the Pennsylvania Railroad located its original power directors office in a substation close to the Thirtieth Street Station. This substation was abandoned and demolished, probably in the mid-1930s. No trace, of the original power director's office equipment was found. It probably featured a non-electric model board with colored pegs which were inserted in a power schematic diagram to indicate electrical status of components. It would have been similar to the octagonal "carousel" schematic board located between the operator's consoles in the power directors office.
The Engineering firm of Gibbs and Hill, which was prominent in several major railroad electrification projects during the early years of the 20th century, was responsible for the concept and engineering design of the new electrically operated display board. About two years after Philadelphia's 30th Street Station was completed and electric passenger service inaugurated on January 16, 1933, the power directors office was activated in room 495. An "installer's mark" was found on the column that supports the schematic carousel implying that the facility went into service on March 3, 1935 at 6:00 P.M.
Control engineers modified the board over the years to reflect changes in the system. Substations were added and removed. Management modified track routings, added and removed catenary and shifted responsibilities for operation. An early computer control system manufactured by Quindar Electronics, Inc. was added to the power director's facility in the late 1960s. This was used to control Earnest Substation and Earnest Junction, a switching station. It used simple integrated circuits and state-of-the-art computer technology to replace a degree of operator control.
The organization of the Southeast Pennsylvania Transportation Authority (SEPTA) to take over the Pennsylvania Railroad commuter lines, resulted in significant changes in the model board's appearance. Lines representing Zoo tower and its 44 KV system were painted over in the 1970s. Technicians painted the board dull black (signal black) to ease operator eyestrain. The paint change was of minimal benefit and the original satin black paint was restored. Most of the overpaint was done with a coating which could be easily removed so that the original board layout could be restored. Technicians repaired many operating deficiencies such as short circuits and defective relays in the 1980s and restored the board to full operating condition. Up to the time operational control was switched over to CETC a few minor problems remained, some cut wires were not tagged and differential operating voltages on the relays and indicating lights occasionally caused problems.
In the early 1980s Conrail stopped running electric engines for their trains and Amtrak decommissioned the "Quindar" set. In the mid-1980s the set was rewired to control substation 11 (Lamokin), which had been controlled from Lamokin tower. When CETC was implemented, Lamokin tower and a number of other towers throughout Amtrak's Northeast Corridor were shut down.
Modern model boards usually feature a linear layout. Facilities are generally designed to extend along one wall of a room. The original Philadelphia power directors board may have been designed to fit available space. However, by wrapping the board around an axis, one or two power directors could easily scan their respective zones from a central point. The designers expanded this concept with the carousel schematic board, any part of which was readily accessible from either power director's console. The carousel displays schematic circuit particulars in greater detail than is shown on the main model board. By rotating the carousel, the power director could access any detailed schematic without moving away from his station. The carousel board used colored pegs to show circuit status. This peg system was probably adapted from the procedure believed to be used on the original non-electric status board used prior to 1935.
The model board schematic displays the 138 KV transmission, 12 KV catenary and 6.9 KV signal circuits. It is a passive board, that is, changes in field equipment status do not automatically change indicating lights on the board. Indicating lights were turned on or off by the power director who manually tripped button switches located on a console adjacent to the operator's desks. When a circuit breaker or switch feeding power to the railroad system is opened or closed, the power director recorded its position by raising or lowering the appropriate button. A series of relays inside the model board then energized lights which showed the extent of activation or de-energization of the catenary circuits. The model board displays white lights to indicate line power is off. Green and red lights respectively, denote switches or breakers are open or closed.
Communication between linemen working along the right-of-way, tower operators, dispatchers and the power director was by telephone. The telephones used were of the coded ringing type and the power director had a key (switch) which would connect him directly to each interlocking location. Operation of this key set up the code for that location and rang the telephone within a period of eight seconds. Substations were grouped together and an electrician in a sub-station could not tell if they were calling him or if the power director was calling another location in the group. The line was a common one and a worker would always have to listen in for a conversation and verify that other workers were not trying to talk on the line before ringing the power director. Wayside phones were located at strategic points along the right-of-way where various workers could call in during the course of duty. These telephones were used extensively by lineman for their switching and clearances. This communication system functioned until replaced in the mid 1980s.
The power director is a highly regarded occupation in railroad labor hierarchy. Linemen in the field depend in large part on the power director for their safety. In the initial years of operation the power director had full authority, taking action on a problem then reporting it to the supervisor. Today, although still an authoritative position, some major decisions which the Power Directors made in the past are referred to their supervisors.
Qualification for a power director's job was normally secured through an apprenticeship. Most power directors started as electricians or linemen and worked in an "Electric Traction" gang. As they became thoroughly familiar with the types and locations of electrical equipment along the right-of-way, an electric traction employee could move on to a job as an assistant power director and remain in that job for twelve to eighteen months, working in the power director's office.
Contemporary practice eliminates the position of assistant power director. A lineman or substation electrician can qualify as power director after a ten to twelve month apprenticeship. The "power director trainee" must pass verbal and written examinations after working side-by-side with an experienced power director. Once 'qualified' they new power director will be added to the 'extra list' until a senior power director permanently vacates a regular position through retirement or promotion. The new power director is allowed to be used for "extra work" created by vacations or absence. He or she remains on a probationary period until they have worked sixty days, then they are listed on the power director's roster.
The load dispatchers and power directors belong to the American Train Dispatchers Association (ATDA). Electricians and linemen are members of the Brotherhood of Maintenance of Way Employees (BMWE). One can go from the BMWE to the ATDA without losing seniority via a tri-party agreement with the carrier and the two unions.
While monitoring the system, power directors were in close contact with Amtrak's load dispatcher, substation electricians, linemen, train dispatchers and tower personnel. Power directors arrange and verify switching operations with the electricians in substations. Orders for opening or closing any of the breakers or switches were given by the power director via telephone to the operators in the interlocking towers.
Some switches could be actuated by remote control personally by the power director or along the right-of-way by linemen. After an order for switch operation was given, it was performed and the worker reported back to the power director. For safety, all verbal communication was repeated to verify the order. Written orders were used in cases where a train dispatcher gave orders through a tower operator to a train. Additional records of conversations between workers were secured starting in the 1970s when the railroad started tape recording all dialogue.
Other duties that power directors performed included maintaining the heat chart. This kept a record of what track heaters were turned on or off at various interlocking locations. The track heaters were used to keep track switches from freezing in severe snow or ice storms. Power directors also monitored outside temperatures and directed pre-heating of stored commuter cars on cold days.
The power director's office could be a moderately noisy place. With the hum of hundreds of alternating current components, alarm bells and whistles, relays clicking and buzzing, the office had a unique sound. It could be a little frightening to the uninitiated.
