Patent ID: 8890509

Claim:
A sensor configured for use in detecting a time-varying current in a conductor, the sensor comprising at least three planar substrates and a set of two sensor elements provided on each of the at least three planar substrates, wherein the two sensor elements of each set are configured such that a magnetic field passing through the two sensor elements in a first direction induces a positive signal in a first sensor element of the set and a negative signal in the second sensor element of the set; wherein the at least three planar substrates are arranged in the form of a polygon around a central axis to define a sensing volume around the central axis and such that the plane of each of the at least three planar substrates does not intersect the central axis, each of the at least three planar substrates being arranged such that a normal to its plane at a point midway between the two sensor elements provided on a respective planar substrate and projected towards the central axis of the sensing volume lie on the same plane; and wherein the central axis is further defined by the time-varying current in the conductor.