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#1




Finding PeaktoPeak Voltage of a Square Wave Using a Multimeter?
Hello,
How can I find the peaktopeak voltage of a square wave produced by a function generator when I only have a TrueRMS multimeter? I'm new at this so if someone could dumb it down for me, I'd appreciate it. Is it possible? Thanks. 
#2




For a squarewave, RMS is the peak voltage.
Or do you need it for duty cycles other than 50%? ETA: RMS  Peak Calculator for different waves
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#4




Quote:
Is duration (T) one period? Thank you. 
#5




The reading of a multimeter is RMS, but since it's meant to give the RMS value of a sine wave, wouldn't it screw something up when its a square wave?

#6




Yes, T is usually the period, or where f is frequency.
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#7




Quote:
If the meter is TRUE  RMS and marked that way, then it will give you the correct RMS voltage of any waveform (up to the frequency ability of the meter) If the meter cost under $40$50 or so, it is probably only True RMS for sinewaves, and the actual voltage of a different waveform is anybody's guess in the case of an Sine RMS only meter.
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#8




The RMS value is what constant DC voltage will give the same heating effect as the signal of arbitrary wave form. Hence mathematically, you have to compute the integral of the square of the amplitude and then take the square root. So when you square the negative portion, it is the same value as the positive part. Hence the RMS is the same as if the square wave was a constant DC signal of half the peaktopeak voltage.
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#9




Quote:
I'll have to look at the datasheet for my meter then. Thank you. 
#10




That meter is a True RMS meter, meaning it will give you the RMS value of any waveform.
It may also give you the peak voltage if you set it to peak record.
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finding, multimeter, peaktopeak, square, voltage, wave 
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