Patent ID: 8378662

Claim:
A current sensor comprising a coil arrangement with an equivalent coil structure of at least three sense coil segments arranged to be located in close proximity to a current conductor in an electricity meter; wherein the sense coil segments are mounted in fixed relation in at least one direction to the current conductor; and a magnetic centre of each sense coil segment is co-located with each other; a first coil segment of said at least three sense coil segments having a number of coil turns wound in a first sense; a second coil segment of said at least three sense coil segments having a number of coil turns wound in an opposite sense to said first coil segment; and a third coil segment of said at least three sense coil segments having a number of coil turns wound in said first sense; the sense coil segments being connected in series; and wherein said at least three coil segments are configured to have different spatial responses; wherein a combined response of signals relative the current in the current conductor from the coil arrangement is proportional to the rate of change of current in the current conductor, and is substantially insensitive to a uniform external AC magnetic field, to a first-order gradient AC magnetic field, and to current in at least one other current-carrying conductor in said electricity meter; said other current-carrying conductor being located in a defined location relative the coil arrangement.