Keysight Technologies 3458A Guide D'utilisation page 266

6 Command Reference
FIXEDZ
The FIXEDZ command enables or disables the fixed input resistance function for
DC voltage measurements. When enabled, the multimeter maintains its input
resistance at 10 megohms for all ranges. This prevents a change in input
resistance (caused by a range change) from affecting the DC voltage
measurements.
Syntax
FIXEDZ [control]
control
The control parameter choices are:
control
parameters
OFF
ON
Power-on control = OFF.
Default control = ON.
Remarks
– FIXEDZ remains enabled when you change from DC voltage measurements to
– FIXEDZ is temporarily disabled when you change from DC voltage
266
Numeric
query equiv.
0
1
2-wire or 4-wire ohms measurements. Resistance measurements made with
FIXEDZ enabled will be in error because the multimeter's input resistance
represents a 10 MW resistance in parallel with the input terminals.
measurements to AC voltage, AC+DC voltage, any type of current, frequency,
or period measurements. For example, if FIXEDZ is enabled and you change
from DC voltage measurements to AC voltage measurements, FIXEDZ
becomes disabled. When you return to DC voltage measurements, however,
FIXEDZ is once again enabled.
Description
DCV .1 V, 1 V, 10 V,
and 1000 V ranges
FIXEDZ disabled
FIXEDZ enabled
Input resistances
DCV 100 V
ranges
>10 GW 10 MW
10 MW 10 MW
Keysight 3458A User's Guide