Current sensing device and monitor
OwnerRaymond J. McAlliseinventor
Life of this patent
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Abstract
A system senses alternating current in a conductor, such as a main line supplying electrical power to a home, and responds to the sensed current as by providing a warning signal when the sensed current exceeds or is less than a preset value for a predetermined short period of time. The current sensor itself is a simple coil of wire, either with an air core or a partial ferromagnetic core, which can be easily operatively associated with the current carrying conductor without the need for disconnecting the conductor from its terminals and which when installed does not present the hazards associated with current transformers.
Claims14
A system for sensing and responding to an alternating current flowing through an electrical conductor, said system comprising a current sensor for sensing the current in at least one conductor and for producing an output voltage related in magnitude to the magnitude of the current flowing through such at least one conductor, said current sensor being a coil of wire wound about a central axis and arranged adjacent to said conductor with said central axis spaced from said conductor and located in a plane non-parallel to said conductor so that some of the flux lines encircling said conductor link with said coil, a substantial portion of the path of said flux lines which link with said coil extending through air, the length of said portion of said flux path which passes through air being considerably longer than the diameter of said conductor so that said coil can be moved sidewise of said conductor into association with said conductor in the course of being assembled with said conductor, a sensing comparator means for comparing the output voltage of said coil with a preset value of voltage and for producing an output signal when the output voltage from said coil departs in one direction from said preset voltage, a duration detector connected with said sensing comparator and operable to produce an output signal when the output from said sensing comparator has persisted for a predetermined amount of time, and means responsive to said output of said duration detector.
A system for sensing alternating current flowing through an electrical conductor and for responding to the sensed value of current, said system comprising a coil of wire wound about a central axis and adapted to be placed adjacent at least one alternating current carrying conductor with its axis located in a plane non-parallel to the axis of the conductor so that some of the flux lines encircling said conductor link with said coil, a substantial portion of the path of said flux lines which link with said coil extending through air, the length of said portion of said flux path which passes through air being considerably longer than the diameter of said conductor so that said coil can be moved sideways of said conductor into association with said conductor in the course of being assembled with said conductor, said coil having two output leads across which an output voltage induced in said coil by the current flowing through said at least one conductor appears, and means connected with said output leads of said coil for responding to the voltage appearing across said leads.
Dependencies are inferred from the claim text.