Keysight Technologies 3458A Guide D'utilisation page 95

APER or NPLC command can also specify an integration time, an interaction
occurs when you specify resolution as follows:
– If you send the APER or NPLC command before specifying resolution, the
– If you send the APER or NPLC command after specifying resolution. the
When to specify resolution
For DC or ohms measurements, you should specify resolution when the resolution
provided by the NPLC or APER command is not sufficient. For example, in the
following program, line 10 specifies 1 PLC of integration time which provides 60
dB of NMR and 7½ digits of resolution. This produces an actual resolution of 1 µV
on the 10 V range. For this application, 100 nV of resolution is required with a
max._input of 10 V. The preceding equation produces a %_resolution parameter
of 0.000001 (1E-6). This is specified in line 20.
10 OUTPUT 722;"NPLC 1"
20 OUTPUT 722;"DCV 10, 1E-6"
30 END
Autozero
The autozero function ensures that any offset errors internal to the multimeter are
nulled from subsequent DC or ohms measurements. The autozero function is
controlled using the AZERO command. With AZERO ON, the multimeter internally
disconnects the input signal and makes a zero reading following every
measurement. It then algebraically subtracts the zero reading from the preceding
measurement. With AZERO OFF or ONCE, the multimeter takes one zero reading
and algebraically subtracts this from subsequent readings. After you execute
AZERO OFF or AZERO ONCE, the multimeter takes the autozero measurement
when the first trigger arm event occurs for all events except TARM EXT which
causes an autozero measurement when the TARM EXT command is executed.
(The trigger arm event is discussed in
updated whenever the measurement function, range, or integration time is
changed (this update is made when the trigger arm event occurs or TARM EXT is
executed). In the power-on/PRESET NORM state, AZERO is set to ON. You can
change it by sending:
Keysight 3458A User's Guide
multimeter satisfies the command that specifies greater resolution (more
integration time).
multimeter uses the integration time specified by the APER or NPLC
command, and any previously specified resolution is ignored.
Configuring for Measurements
Chapter 4.) The autozero measurement is
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