Abstract: Systems and methods are provided for improving the operation of a computer or other electronic device that utilizes root-mean-square (RMS) measurements, e.g., RMS current measurements, by reducing error in the RMS measurement. A series of measurement samples are received at a processor, which executes a noise-decorrelated RMS algorithm including: calculating a current-squared value for each measurement sample by multiplying the measurement sample by a prior measurement sample in the series (rather by simply squaring each measurement sample as in conventional techniques), summing the current-squared values, and calculating an RMS value based on the summed values. The processor may also execute a frequency-dependent magnitude correction filter to correct for frequency-dependent attenuation associated with the noise-decorrelated RMS algorithm.

Abstract: A low cost and easy to assemble communicating utility meter provides selectable measurement, calibration, display, and communications means so as to be re-configurable based on several factors including; harmonic content of the power signal measured, LCD display alternatives, time of use measurements, bandpass filter settings, power quality measurements, PLC communications. alternatives, radio frequency communications alternatives, optical communications alternatives, and hard wire communications alternatives.

Abstract: A trip unit input circuit configured to generate a signal proportional to current in respective phase lines of a power line and to provide operational power from a corresponding primary current transformer, the circuit comprising: a current sensor circuit configured to provide an output signal indicative of current flow through a respective phase line; a secondary current transformer in operable communication with the corresponding primary current transformer; and a power supply circuit coupled to an output winding of the secondary transformer, the power supply circuit being isolated from the current sensor circuit by the secondary current transformer.