Patent ID: 7996171

Claim:
An intelligent electronic device comprising: a sensing circuit having one or more sensors for sensing at least one parameter of an AC electrical service, each of the one or more sensors generating a first signal representative of the sensed parameter; a plurality of gain-adjustable channels, each channel having at least one gain adjustment circuit for individually adjusting a gain factor and each channel comprising at least one first signal generated by the one or more sensors, the at least one first signal representative of the sensed parameter, wherein the plurality of gain-adjustable channels include a first channel for energy calculations, a second channel for harmonics calculations, and a third channel for waveform capture; one or more computer-readable storage devices; and a plurality of calibration factors stored in the one or more computer-readable storage devices, the plurality of calibration factors corresponding to a plurality of calibration measurements, the plurality of calibration measurements comprising measurements of a second signal representative of a known value of the parameter at a plurality of signal amplitudes in each of a plurality of calibration ranges.