US 4,456,873 A · Cable mounted magnetic core assembly

Abstract

A fault indicator for indicating the occurrence of a fault current in an electrical conductor includes a core assembly which attaches a circuit module to a monitored conductor and provides a concentrated magnetic flux indicative of the current level in the conductor. A magnetic reed switch in the circuit module responds to the magnetic flux in the core assembly to condition an indicator in a remote indicator module to a fault-indicating state in the event of a fault. To facilitate installation and removal of the circuit module from the conductor, the core assembly is formed by a plurality of laminations secured together and arranged in a generally rectangular configuration with their ends juxtaposed along one side thereof and joined with magnetically conductive interlocking coupling members. A spring spanning the remaining opposed sides of the core biases the coupling members into engagement and allows the structure to be fitted over conductors of various sizes, while maintaining a close operative association between the conductor and the magnetic reed switch in the circuit module.

Claims32

Dependent claims

A fault indicator for indicating the occurrence of a fault current in an electrical conductor, comprising:

magnetic core means comprising a plurality of elongated strips of resilient magnetic material arranged side by side and joined at the ends thereof to form a magnetic core;
said magnetic core being formed into a closed loop having first, second, third and fourth sides, said first, second and third sides being generally rectilinear, said first side being generally opposite said second side, and said third side joining said first and second sides, said magnetic core being dimensioned to receive within said closed loop said electrical conductor;
interlocking connection means disposed along said third side for establishing a separable connection between segments of said third side, said connection being locked against lateral displacement upon said segments being urged toward axial engagement;
biasing means comprising a spring member extending between said first side and said second side for drawing said sides together whereby said segments are urged toward axial engagement, said spring member being positioned to engage the conductor opposite from said third side to urge the conductor into contact with said third side;
current-responsive means disposed along said third side of said magnetic core in magnetic communication with the conductor for providing a control effect upon the occurrence of a fault current in the conductor;
and
means responsive to said control effect for providing a fault indication.

4 more elements

A fault indicator for indicating the occurrence of a fault current in an electrical conductor, comprising:

magnetic core means comprising a plurality of elongated strips of resilient magnetic material arranged side-by-side and joined at the ends thereof to form a magnetic core;
said magnetic core being formed into a closed loop of generally rectangular form having first, second, third and fourth generally rectilinear sides, said first side being opposite said second side, said third side being opposite said fourth side, and said third side joining said first and second sides, said magnetic core being dimensioned to receive within said closed loop said electrical conductor;
interlocking connection means disposed along said third side for establishing a separable connection between segments of said third side, said connection being locked against lateral displacement upon said segments being urged toward axial engagement;
biasing means comprising a spring member extending between said first side and said second side for drawing said sides together whereby said segments are urged toward axial engagement, said spring member being positioned to engage the conductor opposite from said third side to urge the conductor into contact with said third side;
current-responsive means disposed along said third side of said magnetic core in magnetic communication with the conductor for providing a control effect upon the occurrence of a fault current in the conductor;
circuit means responsive to said control effect for providing a fault indication, said circuit means being operative from an applied excitation source;
and
excitation means comprising a magnetic winding on said third side of said magnetic core for supplying excitation to said circuit means.

5 more elements

A fault indicator for indicating the occurrence of a fault current in an electrical conductor, comprising:

magnetic core means comprising a plurality of elongated strips of resilient magnetic material arranged side-by-side and joined at the ends thereof to form a magnetic core;
said magnetic core being formed into a closed loop having a first, second, third and fourth sides, said first, second and third sides being generally rectilinear, said first side being opposite said second side, and said third side joining said first and second sides, said magnetic core being dimensioned to receive within said closed loop said electrical conductor;
interlocking connection means disposed along said third side for establishing a separable connection between segments of said third side, said connection being locked against lateral displacement upon said segments being urged toward axial engagement;
biasing means comprising a spring member extending between said first side and said second side for drawing said sides together whereby said segments are urged toward axial engagement, said spring member being positioned to engage the conductor opposite from said third side to urge the conductor into contact with said third side;
current-responsive means disposed along said third side of said magnetic core in magnetic communication with the conductor for providing a control effect upon the occurrence of a fault current in the conductor;
circuit means operable from an applied excitation current and responsive to said control effect for providing a fault indication in response to said control effect;
and
excitation means comprising a magnetic winding disposed on said third side of said core for providing excitation current to said circuit means.

5 more elements

Dependencies are inferred from the claim text.

Cable mounted magnetic core assembly

Life of this patent

Cable mounted magnetic core assembly

Life of this patent

Abstract

Claims32