Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
254 words
A current meter including a first voltage source (110) for providing a first frequency signal to a winding (300-1) enclosing a magnetic core (200-1), said core adapted to be coupled to the magnetic field surrounding a conductor (400-1), means responsive to said first frequency signal for measuring the current through said conductor, said measuring means including means (120) for detecting a harmonic of said first frequency signal, and means for reducing said detected harmonic and characterized in that said meter further comprises means adapting said meter for remotely measuring current through a plurality of conductors (400-1, . . .400-N), said remote measuring means including means (500, 510-1, . . .510-N, 520-1, . . .520-N) for selecting one of said conductors, means for extending said first frequency signal to a selected one of a plurality of windings (300-1, . . .300-N), said selected winding enclosing a selected one of a plurality of magnetic cores (200-1, . . .200-N), said selected core adapted to be coupled to the magnetic field surrounding said selected conductor, and said harmonic reducing means including a second voltage source (190), means (150, 600, 160) for extending a reference current from said second voltage source through said selected winding, and means (170) for displaying the magnitude of said reference current, means (180) for controlling the magnitude of said reference current, and means (140) for displaying the magnitude of said harmonic whereby the magnitude of said reference current equals the magnitude of the current in said selected conductor when said harmonic is minimized.
Claim 2
Dependent Claim
254 words
A current meter including a first voltage source (110) for providing a first frequency signal to a winding (300-1) enclosing a magnetic core (200-1), said core adapted to be coupled to the magnetic field surrounding a conductor (400-1), means responsive to said first frequency signal for measuring the current through said conductor, said measuring means including means (120) for detecting a harmonic of said first frequency signal, and means for reducing said detected harmonic and characterized in that said meter further comprises means adapting said meter for remotely measuring current through a plurality of conductors (400-1, . . .400-N), said remote measuring means including means (500, 510-1, . . .510-N, 520-1, . . .520-N) for selecting one of said conductors, means for extending said first frequency signal to a selected one of a plurality of windings (300-1, . . .300-N), said selected winding enclosing a selected one of a plurality of magnetic cores (200-1, . . .200-N), said selected core adapted to be coupled to the magnetic field surrounding said selected conductor, and said harmonic reducing means including a second voltage source (190), means (150, 600, 160) for extending a reference current from said second voltage source through said selected winding, and means (170) for displaying the magnitude of said reference current, means (180) for controlling the magnitude of said reference current, and means (140) for displaying the magnitude of said harmonic whereby the magnitude of said reference current equals the magnitude of the current in said selected conductor when said harmonic is minimized.
Claim 3
Dependent Claim
61 words
The meter defined in claim 1 wherein said second voltage source and said reference current extending means further comprises a dc current source for removing a magnetic bias in said selected core, said bias being introduced responsive to said current in said selected conductor whereby the magnitude of said dc current equals the magnitude of the current in said selected conductor.