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

220V_71.png (106.85 KiB) Viewed 115997 times

Method 2

220V_81.png (118.69 KiB) Viewed 115997 times

Method 3

220V_91.png (99.01 KiB) Viewed 115997 times