Electricity meter and associated method

Abstract

An electricity meter 2 for measuring properties of an electrical input 6 from a power supply, comprises a first analogue-to-digital converter (ADC) 10a, a second ADC 10b and a processor 12. The first ADC receives an input signal 18 derived from the electrical input, e.g. from a voltage divider or burden resistor 8, and generates a first ADC output data sequence 20a. The second ADC receives the input signal and generates a second ADC output data sequence 20b. The processor determines a cross-correlated average data sequence 40 based on the first and second ADC output data sequences and determines one or more properties of the electrical input based on the cross-correlated data. Sampling or thermal noise in the two ADC channels is uncorrelated and calculating the cross-correlation between the two channels reduces this uncorrelated noise. The processor may reverse the time order sequence of the first or second ADC output data before performing the correlation.

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