How to Measure Mains / Line Voltage and Harmonic Distortion

[VirtinsTech]

This video demonstrate three methods to measure the voltage and harmonics of an AC power supply using a USB oscilloscope with passive probes. The three method are: (1) Earth-Grounded Single-Ended Measurement (2) Earth-Grounded Differential Measurement (3) Floating-Ground Differential Measurement.

[youtube]http://www.youtube.com/watch?v=oMqhrRUjxOg[/youtube]

Method 1

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Method 2

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Method 3

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