Why mains voltage not perfectly sinusoidal !!!

Thread Starter

Mohamed87

Joined May 1, 2010
6
Hi, I don't know if it's only the case for me, but I noticed that the mains voltage I measured in my lab (in europe - France) is not a perfect sinusoid but instead it's somehow clipped from the top and buttom (see joint figure).
Does anyone have an idea where it might come from ?

Thanks !Tension_secteur_sonde_pico.png
 

DickCappels

Joined Aug 21, 2008
10,152
What you are seeing is normal in a lot of places. It may well look different at different times of the day. A lot power supplies only draw appreciable current during the peaks, resulting in these flattened sine waves. This was one of the reasons the EU brought power factor rules into play back around the turn of the century.
 

Lectraplayer

Joined Jan 2, 2015
123
Does anyone have an idea where it might come from ?
View attachment 83184
To be specific, anything that pulls power on peaks, which includes most anything electronic. (computers, fluorescent lamps, battery chargers) I bet this would be the majority of your loads. This can do some wierd stuff to your electrical system. If you have something sensitive, you can filter the power with a choke coil.
 

Thread Starter

Mohamed87

Joined May 1, 2010
6
Thanks a lot everybody for your answers, I think I understand now :) Basically, it's caused by everything that draws power essentially on peaks which gives rise to voltage drops and distortion of the form around the peaks.

Regards,
 
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