Electrical current transducer with grounding device

A method of making a magnetic circuit of an electrical current transducer, the transducer comprising a housing, a magnetic field detector device comprising a magnetic field detector, and a magnetic circuit comprising a wound magnetic core with a gap and a grounding device mounted on the magnetic core, the wound magnetic core comprising a plurality of stacked concentric ring layers from a radially innermost layer to a radially outermost layer of magnetic material, the magnetic field detector being positioned in the gap, wherein the grounding device comprises at least two parts made of a non-magnetic material, a first part mounted against a first lateral side of the magnetic core and a second part mounted against a second lateral side of the magnetic core opposite the first lateral side, at least one of the first and second parts comprising clamp fixing extensions cooperating with the other of the first and second parts configured for clamping together the first and second parts around a portion of the magnetic core whereby free ends of clamp fixing extensions arranged on the second part are inserted through corresponding cavities of the first part and wherein at least one of the first and second parts comprises electrically conductive material, said part comprising at least one contact terminal being adapted to provide an electrical grounding connection for grounding the magnetic core to an external ground conductor, the method including the steps of:

• forming said wound magnetic core by
• winding a magnetically permeable strip material to form a stacked multilayer ring core;
• annealing the stacked multilayer ring core;
• fixing the layers of the ring core, for instance by welding or resin impregnation;
• machining a gap through a section of the stacked multilayer ring core;
• mounting the first and second parts of the bridging device around the wound magnetic core such that the fixing extensions of the second part are inserted through the corresponding clamp extension receiving cavities of the first part;
• crimping the ends of the fixing extensions such that the two parts are clamped together tightly against opposite lateral sides of the wound magnetic core.