Combined low frequency and high frequency current sensor

A low frequency current measurement power metering device, comprising:

• a core bead body composed of a ferromagnetic, ferrite, or magnetic oxide material having a generally toroidal shape with a radial thickness extending between a circumferential periphery and an inner periphery surrounding a centralized circular aperture through which passes a current carrying power wire, and an air cavity formed in the core bead body with sidewalls substantially perpendicular to the circumferential periphery and extending radially inwardly for a distance less than the radial thickness forming a bottom of the cavity separated from the inner periphery of the core bead body surrounding the centralized circular aperture by a remaining thickness of the core bead body forming a shielding bridge portion, configured to provide a magnetic shield for the air cavity from variations in magnetic flux due to variations in distance of the power wire from the inner periphery of the core bead body to enable measurement of magnetic flux in the air cavity, having a power wire passing through the bead;
• and
• a magnetic flux-density sensing device embedded in the air cavity in the core bead body, having a magnetic field sensing surface oriented substantially perpendicular to the circumferential periphery of the core bead body, configured to provide measurable low frequency magnetic flux through the magnetic flux-density sensing device in response to current signals with low frequencies in the power wire, the magnetic flux-density sensing device configured to provide low frequency current measurement in response to an occurrence of the low frequency measurable magnetic flux.