Features and Functions
3
Keysight 34980A Mainframe User’s Guide
125
– The
CONFigure
and
MEASure?
commands contain an optional parameter
which allows you to specify the range or autoranging.
– The instrument returns to autoranging when the measurement function is
changed and after a Factory Reset (
*RST
command). An Instrument Preset
(
SYSTem:PRESet
command) or Card Reset (
SYSTem:CPON
command) does
not
change the range setting.
Front Panel Operation:
DMM or Channel (Configure) > RANGE
First, select the measurement function on the active channel. You are
automatically guided to the next level of the menu where you can select a specific
range or autoranging.
Remote Interface Operation:
You can select the range using parameters in the
CONFigure
and
MEASure?
commands. For example, the following command
selects the 10 Vdc range on the specified channel.
CONF:VOLT:DC 10,DEF,(@3001)
Measurement Resolution
Resolution is expressed in
number of digits
the internal DMM can measure or
display on the front panel. You can set the resolution to 4, 5, or 6 full digits, plus a
“½” digit which can be “0” or “1”. To increase the measurement accuracy and
improve noise rejection, select 6½ digits. To increase the measurement speed,
select 4½ digits.
– For ac voltage measurements, the resolution is fixed at 6½ digits. The only way
to control the reading rate for ac measurements is by changing the channel
delay (see
on page 161) or by setting the ac filter to the
highest frequency limit (see
– The specified resolution is used for all measurements on the selected channel.
If you have applied Mx+B scaling, have assigned alarms to the selected
channel, or are in Monitor mode, those measurements are also made using the
specified resolution.
– Changing the number of digits does more than just change the resolution of
the instrument. It also changes
integration time
, which is the measurement
sampling period for the instrument’s A/D converter. See
on page 127 for more information.
