Voltage measurement configuration, Dc input resistance – Agilent Technologies Switch/Measure User Manual
Page 47
Features and Functions
2
34980A User’s Guide
35
Voltage Measurement Configuration
This section contains information to help you configure the instrument for
making voltage measurements. The instrument can measure dc and true
RMS ac- coupled voltages on the measurement ranges shown below.
DC Input Resistance
Normally, the instrument’s input resistance is fixed at 10 M
Ω
for all
dc voltage ranges to minimize noise pickup. To reduce the effects of
measurement loading errors, you can set the input resistance to greater
than 10 G
Ω
for the 100 mVdc, 1 Vdc, and 10 Vdc ranges.
Applies to dc voltage measurements only.
• The
CONFigure
and
MEASure?
commands automatically select AUTO OFF
(fixed at 10 M
Ω
for all ranges).
• The instrument selects 10 M
Ω
(fixed input resistance on all dc voltage
ranges) after a Factory Reset (
*RST
command). An Instrument Preset
(
SYSTem:PRESet
command) or Card Reset (
SYSTem:CPON
command)
does not change the input resistance setting.
Front Panel Operation:
DMM or Channel (Configure) > INPUT RESISTANCE
Remote Interface Operation:
You can enable or disable the automatic
input resistance mode on the specified channels or the internal DMM.
With AUTO OFF (default), the input resistance is fixed at 10 M
Ω
for all
ranges. With AUTO ON, the input resistance is set to >10 G
Ω
for the three
lowest dc voltage ranges.
[SENSe:]<function>:IMPedance:AUTO {OFF|ON} [,(@<ch_list>)]
If you omit the optional <ch_list> parameter, the command applies to the
internal DMM.
100 mV
1 V
10 V
100 V
300 V
Autorange
DC input resistance
Input Resistance Setting
Input Resistance for:
100 mV, 1 V, 10 V ranges
Input Resistance for:
100 V, 300 V ranges
Input Resistance: Auto OFF
Input Resistance: Auto ON
10 M
Ω
> 10 G
Ω
10 M
Ω
10 M
Ω