Faulted circuit detector having isolated indicator
CA 2086331 C · Owner: Rector, Gary D. · Inventors: Rector, Gary D.; Dunk, Michael P.; Banting, John F.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A faulted circuit detector (10) having an electrically isolated and remotely positioned indicator (14) detects fault currents in a monitored conductor (18). When a fault of a predetermined magnitude is detected, a light pulse is transmitted from the detector to the indicator via a fiber optic cable (15) where upon receipt, the pulse , is converted to an electrical pulse causing the indicator to indicate a "fault" state. A reset circuit (56) within the indicator resets the indicator at regular intervals to the "normal" state as long as a predetermined minimum voltage is present on the monitored conductor. The detector includes a temperature compensation circuit (150) and low pass filter …
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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
- Filed June 21, 1991 and granted December 19, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 21, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 21, 2013.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
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.