Vrms VS Vpp (120Vrms != 339Vpp) MS12.0.1

[Who_Knew]

Hi Folks,

There's something wrong with Multisim's simulated relationship between Vrms and Vpp.  Does anyone else see it?  I can't seem to convince National Instruments of it. 

No need to reply if you're just going to cite one of the many wrong sources of information on the Internet.

Please do reply if you've ever actually measured 60Hz 120 Vrms with a real instrument, such as a multimeter, and have also actually measured the same voltage using a real oscillocsope.

[Miguel_V]

Hi Greg,

If I could direct you to this wiki article, it denotes the relation between current/voltage at peak and rms. It goes through the derivation of the form as through simple series as well as sinusoidal functions. If you understand integrals and limits then this should be a pretty simple concept to read up on. It should also explain why 120Vrms is infact 340Vpp, as 120Vrms=170Vp and 170Vp=340Vpp.

I don't own an oscilloscope, but from what I remember in my University years, I'm pretty sure this is right and this is the relationship you'd see in an oscilloscope that is calibrated to show you peak-to-peak not just peak.

http://en.wikipedia.org/wiki/Root_mean_square

Kind Regards,

[johnsold]

I have been an electrical enfgineer for 40+ years and 120.00 Vrms on a sine has been 169.71 Vpk and 399.41 Vpp for all of those years.

What do you think it should be and why?

Lynn