A device for monitoring the properties of an electrical grid including an electrical connector for coupling to the electrical grid through a wall socket, a detector for detecting at least one property of electricity provided by the electrical grid, a receiver for receiving clock signals, and a sampler for sampling a respective detected property and recording sampled values in a memory, wherein the variation of the values with time represents a waveform of the respective property and the sampler samples at a rate sufficient to record variations of the property within a period of the waveform, wherein the device associates at least a portion of the sampled values with at least one clock signal.
Patent Number: 9,825,463
Date Issued: November 21 2017