Measurement Speed Consideration - Keysight 34450A Guia Del Usuario

3 Measurement Tutorial

Measurement Speed Consideration

There are two methods of integrating the sampled data taken in the
measurement, slow/medium (NPLC) and fast (Aperture).
When you set the resolution to slow or medium, you can not only achieve
improved accuracy associated with time averaging, but also achieve the rejection
of the power-line interference (normal mode rejection, or NMR).
Aperture is the period, measured in seconds, during which the multimeter's
analog-to-digital (A/D) converter samples the input signal for a measurement.
A longer aperture yields better resolution; a shorter aperture provides faster
measurements. The fast mode set a specific 1 ms measurement period, not based
on power line frequency. No normal mode rejection is provided in aperture mode.
100 Keysight 34450A User's Guide