AC current or voltage sensor

A method for producing a signal indicative of an alternating current flowing in a conductor, the method comprising:

• providing a support element defining a main central axis and having a central opening extending axially therethrough for accommodating the conductor substantially coaxially to the support element,
• providing a carrier comprising an elongated primary substrate defining opposite first and second major surfaces,
• bending the primary substrate along spaced apart transversely extending bend lines into a multi-channel arcuate configuration defining a plurality of adjacent channels having opposite side walls,
• locating the primary substrate in the support element in the multi-channel arcuate configuration extending around the main central axis with the bend lines and the channels extending substantially parallel to the main central axis, and the side walls defining planes extending substantially longitudinally along and substantially radially from the main central axis,
• forming a plurality of planar coils on the first and second major surfaces of the primary substrate on the respective side walls of the channels with the planar coils defining respective planes extending substantially along and substantially radially from the main central axis of the support element and being spaced apart circumferentially around the main central axis,
• providing a shield means shield for minimizing the effect of external stray electric and magnetic fields in the vicinity of the current sensing device on the planar coils,
• electrically connecting the planar coils in series so that voltages induced in the planar Coils the alternating current flowing in the conductor are summed in phase to produce the signal indicative of the alternating current flowing in the conductor, and
• locating the conductor in the central opening extending coaxially through the central opening of the support element, and
• reading the produced signal indicative of the alternating current flowing in the conductor.