Keysight Technologies 3458A Guide D'utilisation page 439

convenience. The HPML commands that most affect the throughput speed from a
measurement viewpoint are:
FUNC<DCV, DCI, OHM, FOHM>,<range>,<resolution in %>
NPLC #
APER<integration period s>
RES <resolution in %>
AZERO,<on or off>
In
interchangeable. The significant difference between these two commands is that
NPLC actually uses the power line frequency to establish the integration period
for the chosen multiple or submultiple of the line frequency. The APER command
sets the integration period in fundamental units of seconds from 500 ns to 1 s in
100 ns steps. Operating at 60 Hz line frequency, for example, the choice of NPLC
1 is equal to APER 0.016666.
Figure D-1
Keysight 3458A User's Guide
Table D-1 you'll see that NPLC and APER commands are somewhat
Shows the dependency of accuracy, reading rate, resolution,
and noise on aperture or NPLC selected
Optimizing Throughout and Reading Rate D
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