ITTSB.EU Blog Forum
Multimeter | Clamp meter | Insulation Resistance Tester | Panel Meter | Oscilloscopes | Test leads & Accessories | Software Updates => Handheld multimeter => Topic started by: Kiriakos GR on July 25, 2015, 09:53:27 PM
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In several multimeter user guides there is the description of: Peak to Peak Volts 100ms, but the major question is what this information worth? One plain number is not easy to be understood, especially when a newcomer is trying to use any offered specification as to be a comparison point so him to form a buying decision about a new multimeter.
In order to personally understand what this 100ms translates to, I had to use my oscilloscope and my function generator.
Basically those 100ms translates to a portion of time in which the measuring device using this as to be a paper sheet for taking notes.
My experiment made me to understand that 100ms it is a huge time interval compared to the needed one of 5ms so 50Hz ACV this to be measured and reviewed by an Oscilloscope.
Therefore the next question is why a multimeter must to wait that long (100ms) at collecting measurements’ prior showing the measured value on the screen?
The answer is that those 100ms which are also called as peak window is the needed time so two waves at about 2Hz to be recorded at our hypothetical paper sheet, so those to be measured by the multimeter and the outcome of the measurement to be considered as correct.
In measurements’ the more available waveforms (data points) in the unit of time is what helps the measuring device to give a more accurate reading.
In the screen shots bellow there is three pictures for you to see.
The first is just a proof of 5ms needed for measuring 220V at 50 Hz.
The second is what the oscilloscope records as portion of waveform at 100ms of time, with 2Hz incoming signal.
The third is the same waveform but scaled to 200ms time division, as you can see this definably looks as paper sheet which what is on it, is the data that the measuring device have to measure.
In conclusion this 100ms peak window is there so to assist slow waveforms as for example the ones starting at 1Hz so even them to be recorded and measured properly.