Modified offset keying apparatus for phase comparison relaying
CA 1085953 A · Owner: Westinghouse Electric Corporation · Inventors: Hinman, Walter L. Jr.; Gonnam, Russell W.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Phase comparison relaying apparatus wherein the keying threshold levels at the local and remote ends of a protected power line section are each offset by a different value from the effective zero axis of the current waveform. One of the keying threshold values is set at a magnitude which will cause a trip response in the presence of low or medium magnitudes of outfeed current. The other keying threshold level is set at a magnitude which will cause a trip response in the presence of maximum magnitudes of expected outfeed current. The upper and lower current margin threshold levels are set to appropriately reflect the keying threshold level with which they are respectively associated. In …
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Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Granted September 16, 1980. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended September 16, 1997.
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Timeline
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Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.