Electrical power systems recordsCreation: 1904-2014
The Leeds & Northrup Company thrived throughout the twentieth century as a premier manufacturer of precision measuring and scientific equipment. The bulk of the Leeds & Northrup Electrical Power Systems records come from three employees, whose work at Leeds & Northrup spanned from 1928-1981: W. Spencer Bloor (1918-2002), Nathan Cohn (1907-1989), and S. Byron Morehouse. All worked within the Instrumentation and Controls for Electric Power Application Division. The records include papers, presentations, correspondence, memos, blueprints, and other materials relating to the development of a national electrical power grid in the United States. Technological and commercial developments in automatic electric power generation control, stabilization of energy load across regions, and problems of interconnection feature prominently in these materials.
- Creation: 1904-2014
- North American Power Systems Interconnection Committee (Author, Organization)
- Leeds & Northrup Company (Author, Organization)
- Cohn, Nathan, 1907-1989 (Author, Person)
3 Linear Feet
General Physical Description
The Leeds & Northrup Company began in 1903 with the partnership of Morris E. Leeds (1869-1952) and Dr. Edwin F. Northrup (1866-1940), in Philadelphia, PA. Throughout the twentieth century, the company thrived as a premier manufacturer of precision measuring and scientific equipment, including pyrometers, galvanometers, potentiometers, Wheatstone bridge, resistances, condensers, and inductances. In 1978, the General Signal Corporation of Stanford, Connecticut acquired the company, turning it into the Leeds & Northrup Metallurgical Products Division. In 1995, General Signal sold their Metallurgical Products Division to Heraeus Holding, GmbH of Hanau, Germany.
The bulk of the Leeds & Northrup Electrical Power Systems come from three employees: W. Spencer Bloor (1918-2002), Nathan Cohn (1907-1989), and S. Byron Morehouse. All worked within the Instrumentation and Controls for Electric Power Application Division; their cumulative years of employment spanned from 1928 to 1981. Cohn was the most prominent and well-recognized of the three; he served for 48 years at Leeds & Northrup, publishing over 90 articles, 15 patents, and one book during his career. He was a fellow of and received awards from both the Institute for Electrical and Electronics Engineers and the Franklin Institute. S. Byron Morehouse was also named an IEEE fellow in 1976, “For contributions to generation control techniques for large-scale interconnected electric power systems.” Likewise, W. Spencer Bloor was elected to the National Academy of Engineering in 1979 for his “contributions to reliability and economy of electric power production through design and application of complex control systems.”
The first two boxes of the Leeds and Northrup collections represent the original nine boxes as cataloged by W. Spencer Bloor in 1990. Those boxes are organized by original box number and original folder number where given; in the first box, Hagley is presumably missing an original folder marked "Box I Papers and Talks, 1927-1949; 4 out of 6." When lacking original folder order, the folders are roughly chronological. An item inventory of the contents of the original nine boxes can be found in the first folder of the first Hagley box; it contains an index prepared December 1990 by W. Spencer Bloor. The third box contains materials without original box designations, coming from the North American Power Systems Interconnection Committee (NAPSIC). Those materials were sorted by content and then arranged alphabetically by folder name. Within each folder, chronology determines the order of papers.
Scope and Content
The Leeds and Northrup Electrical Power Systems records include papers, presentations, correspondence, memos, blueprints, and other materials relating to the development of a national electrical power grid in the United States. Leeds & Northrup Co. employees Bloor, Cohn, and Morehouse were influential in coordinating the creation of a national, interconnected electrical grid in the United States over the mid-twentieth century. The records illustrate how they navigated the economic, commercial, and technological obstacles to interconnection on the regional level in the 1940s and 1950s, and then coordinated of energy flows on the national level as they helped close the East-West ties in the 1960s. However, the papers are not confined to the activities of Bloor, Cohn, and Morehouse, nor restricted to the activities of Leeds & Northrup; the research, reports, and work of many other electrical engineers appear, and the work of such professional organizations as the American Institute of Electrical Engineers and the North American Power Systems Interconnection Committee, among others.
Box one is largely content published in outlets including Electrical World, Power, Electric Light and Power, Business Week, and American Institute of Electrical Engineers and American Power Conference proceedings. The second box is the remainder of the materials originally cataloged by Bloor, but contains much more unpublished material under the “Product Data” heading, including correspondence, wiring diagrams, internal reports, and various committee meeting notes. The third and final box contains materials not included in the original nine boxes of W. Spencer Bloor; these materials are predominantly unpublished. A significant amount of materials focus on solutions to technological problems with large-scale integration, including frequency bias and decomposition, as well as the opportunities presented by the application of new computer technology to automatic generation control.
Records are subject to a twenty-five year time seal from the date of their creation.
Language of Materials
The bulk of the papers were originally collected by W. Spencer Bloor over the course of his career. He donated them to the North American Electric Reliability Corporation (NERC). NERC in turn loaned them to DNV-KEMA ( named DNV-GL as of 2013 – an international certification and classification society). It was from DNV-KEMA that Julie Cohn , daughter of Nathan Cohn, borrowed the original Bloor collection, to conduct research for her doctoral dissertation in history at the University of Houston entitled “Biography of a Technology: The North American Power Grid Through the Twentieth Century.” Cohn also received materials from former Leeds& Northrup engineers at DNV-KEMA from the North American Electric Reliability Corporation predecessor organization, the North american Interconnection Committee (NAPSIC). Between a third and a quarter of the collection are these NAPSIC papers. After defending in 2013, Julie Cohn facilitated the donation of the Bloor collection and NAPSIC materials to the Hagley library in 2014 with the approval and encouragement of DNV-KEMA and NERC officials.
AEP – American Electric Power (Corporation)
AGC – Automatic Generation Control
AIEE – American Institute of Electrical Engineers (in 1962 merged with Institute of Radio Engineers to form IEEE)
EEI – Edison Electric Institute
EIA – Energy Information Administration
EPRI – Electronic Power Research Institute
IEEE – Institute of Electrical and Electronics Engineers
L&N – Leeds & Northrup
NAPSIC – North American Power Systems Interconnection Committee
NERC – National Electric Reliability Council
- Institute of Electrical and Electronics Engineers (Organization)
Finding Aid & Administrative Information
- Electrical power systems records
- Anastasia Day
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- Describing Archives: A Content Standard
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