NESC: The First 100 Years
Don Hooper
Chair, NESC Interpretations Subcommittee
EC&S, Inc.
Contents
¾ Life 100 Years Ago
¾ The Need for the NESC
¾ The Development of NESC 1914-1918
¾ The Early Years 1926-1973
¾ Major Events 1973 to Present
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Courtesy of Engineering and Technology History Wiki
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Courtesy of Engineering and Technology History Wiki
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Courtesy of Archives & Special Collections, University of Connecticut Libraries
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Courtesy of Archives & Special Collections, University of Connecticut Libraries
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Life 100 Years Ago
¾ Early electric supply and communications systems were
isolated systems serving a specific town or area
–  Constructed without standardization of clearances,
strengths of materials, construction methods, or
operation
¾ As a result of the lack of standardization between systems
and across systems:
–  problems for electrical workers
•  traveling from one area to another
•  working in different manufacturing facilities
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The Need for the NESC
¾ Independent operations
¾ Lack of uniform construction and operation
standards
¾ Little, if any, formal training
¾ Poor safety record
–  Accidents and fatalities occurred regularly
•  Not just workers, also the public
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The Development of the NESC 1914-1918
¾  National Bureau of Standards (NBS) initiative
¾  First NBS Circulars informational
-1914: Work rules
-1915: Included construction standards
¾  New York Conference on the NESC: 1915
-Two weeks, 85 participants, all interests represented
-Differences of opinions with good reasons
-Good feeling and a spirit of cooperation
¾  NBS Circulars
-1916: NY Conference results adopted for trial and constructive
criticism
•  Safety Code, not a Construction Manual
•  Included Discussion and Appendices
¾  1918: Ready for General Adoption (cautious)
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The Early Years 1926-1973
¾ 1926 (4th Edition)
–  Hooper born
–  Hooper climbing pole
¾ 1948 (5th Edition)
–  Hooper used NESC as field engineer (PSE&G)
¾ 1961 (6th Edition)
–  Hooper transferred to general office - 1961
–  Discussion, not published
• Hooper involved in NESC – 1969
¾ 1973: IEEE becomes Administrative Secretariat
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Major Events 1973 to Present
¾  1977 Edition: Retroactive application not required
¾  1973 to 1990
–  Emphasis on clearances
–  1990 Edition: Uniform System of Clearances adopted (Appendix A)
•  Changed from 60 degree F to Maximum Sag
¾  1991: Hooper becomes Chair of NESC Interpretations Subcommittee
¾  1993 Edition: Revision cycle changed from 3 years to 5 years
- 1997 Edition, interim 4 years
¾  1997 Edition: Metric (SI) System values take prominence
¾  1997 to Present
–  Emphasis on strength and loading
–  2002 Edition: Consideration of LRFD began
–  2007 Edition: Alternate Method for Load Factors and Strength Factors
phased out, effective July 2010
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Questions?
Don Hooper
[email protected]
NESC Interpretations Webpage
http://standards.ieee.org/about/nesc/interps.html
NESC 100th Anniversary Infographic
http://standards.ieee.org/about/nesc/100/
index.html
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