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Method of locating ground faultsThe present invention discloses a method of detecting and locating current imbalances such as ground faults in multiwire systems using the Faraday effect. As an example, for 2-wire or 3-wire (1 ground wire) electrical systems, light is transmitted along an optical path which is exposed to magnetic fields produced by currents flowing in the hot and neutral wires. The rotations produced by these two magnetic fields cancel each other, therefore light on the optical path does not read the effect of either. However, when a ground fault occurs, the optical path is exposed to a net Faraday effect rotation due to the current imbalance thereby exposing the ground fault.
Document ID
Document Type
Other - Patent
Patterson, Richard L.
(NASA Lewis Research Center Cleveland, OH, United States)
Rose, Allen H.
(NASA Lewis Research Center Cleveland, OH, United States)
Cull, Ronald C.
(NASA Lewis Research Center Cleveland, OH, United States)
Date Acquired
August 17, 2013
Publication Date
November 15, 1994
Subject Category
Electronics And Electrical Engineering
Distribution Limits
Work of the US Gov. Public Use Permitted.
Patent Application

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