Measurement Tutorial
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For the best AC noise rejection, you should perform the DC
measurement at 20 NPLC.
True RMS accuracy and high-frequency signal content
A common misconception is that "since an AC digital
multimeter is true RMS, its sine wave accuracy specifications
apply to all waveforms." Actually, the shape of the input
signal can dramatically affect the measurement accuracy
especially when that input signal contains high- frequency
components which exceed the instrument's bandwidth.
U2741A User's Guide
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