| Typ | Manufacturer |
|---|---|
| Webseite | https://www.selinc.com/ |
| Telefonnummer | +1.509.332.1890 |
| Adresse | 2350 NE Hopkins Court - Pullman, WA 99163 USA |
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In 1982, Edmund O. Schweitzer, III, invented the first microprocessor-based digital protective relay. The SEL-21 was the culmination of research done for Schweitzer's doctoral thesis, and it ushered in a new era of power system protection and went on to revolutionize the electric power industry.
