Lemelson-MIT Program
Who We Are Awards Outreach News
Invention Dimension Search Site Map Contact Us
Inventor of the Week

Inventor of the Week Archive

Browse for a different Invention or Inventor


Digital protective relay systems

Ed Edmund Schweitzer has won fame as an engineer and entrepreneur, for making and marketing the first digital relay systems for electric power plants.

Schweitzer was born in Evanston, Illinois in 1947. He inherited more than a name from his father, Edmund O. Schweitzer Jr., and his grandfather, Edmund O. Schweitzer: both were inventors and electrical engineers. Edmund III followed right in their footsteps, earning a B.S. and M.S. in Electrical Engineering from Purdue University, then a Ph.D. in the same field from Washington State University (WSU), where he also taught for a time.

The subject of Schweitzer's doctoral thesis was digital protective relay systems. Generally, a "relay" is an electromechanical switch that allows the variation of current in one circuit to control the flow of current in another circuit. A protective relay system ensures the steady and timely flow of electricity over a large area by instantly compensating for any irregularities that arise (due to lightning strikes, for example) throughout a utility's power grid. Schweitzer led protective relay systems into the digital age.

In 1982, Schweitzer founded Schweitzer Engineering Laboratories, Inc. (SEL), in his basement. Like his grandfather, who co-founded S&C Electrical Co. on the basis of his first invention, Schweitzer was a success. By 1985, his company was manufacturing --- and selling at a profit --- the world's first fully digital protective relays. The digital units are more efficient and versatile than their electromagnetic predecessors, but are also more compact and inexpensive. Today, SEL employs 300 workers in four buildings, and the company sells its once revolutionary equipment, which protects motors, transformers, feeders, transmission lines, and other electrical apparatus, in fifty-two countries around the world.

Schweitzer is still SEL's leading Inventor. Since just before the company's founding, he has earned two dozen patents, for fault detectors, relay filters, meters, monitors, and other electrical devices. His most recent patent (#5,805,813, granted Sept. 8, 1998) was for an automated visual monitoring system, which scans the dials and gauges of a power station's master control room and warns of any deviation from pre-programmed acceptable standards.

Schweitzer is also SEL's President --- and, like the founders of Hewlett-Packard, he has won a reputation for innovative management. He is known for being accessible to, and listening to, his employees; he values creativity and flexibility in his employees above all else; his company is employee-owned; and his company makes generous donations to nearby WSU and local schools' math and science programs.

Although Edmund Schweitzer is much appreciated in Pullman, Washington, he often travels around the world, either promoting his business or lecturing before academics and industry experts. At the age of 51, Schweitzer has already taken his family tradition to new realms; and he doubtless has a great deal of success yet ahead.

[Dec. 1998]

Invention Dimension
Inventor of the Week Inventor of the Week
Inventor's Handbook Inventor's Handbook
Games & Trivia Games & Trivia
Links & Resources Links & Resources