40
Agilent E1412A Multimeter Application Information
Autozero
Autozero applies to dc voltage, dc current and 2-wire resistance
measurements. The multimeter internally disconnects the input signal
following each measurement and takes a
zero reading
when autozero is
enabled. Autozero enabled is the default setting. It then subtracts the zero
reading from the preceding reading. This prevents offset voltages present on
the multimeter's input circuitry from affecting measurement accuracy.
•
When autozero is disabled (
OFF
), the multimeter takes one zero
reading and subtracts it from all subsequent measurements. It takes a
new zero reading each time you change function, range or integration
time. You can disable autozero on dc voltage, dc current and 2-wire
ohms measurements only (it is always disabled for ACV and ACI
functions). Autozero is always enabled when you select 4-wire ohms
or ratio measurements.
•
The autozero mode is stored in volatile memory. The multimeter
automatically enables autozero at power-on and after a module reset.
•
Use the following command to disable autozero or select the
ONCE
parameter. The
OFF
and
ONCE
parameters have a similar effect.
Autozero
OFF
does not perform a new zero measurement. Autozero
ONCE
performs an immediate zero measurement.
[SENSe:]ZERO:AUTO OFF|ONCE|ON
Ranging
You can let the multimeter automatically select the range using autoranging
or you can specify a range. If you specify an expected value for the signal
you are measuring, the multimeter selects the range to accommodate the
expected input signal and turns autoranging off. Specify a range for faster
measurements to eliminate the autoranging time.
•
The multimeter has autorange mode enabled at power-on and after a
module reset.
•
Autorange thresholds:
Down range at <10% of range.
Up range at >120% of range.
•
The multimeter will provide an overload indication by returning
"9.9037"
if the input signal is greater than the present
range can measure and autoranging is disabled or at the maximum range
setting.
•
The multimeter uses one “range” for all inputs between 3Hz and
300kHz for the frequency and period functions. The multimeter
determines an internal resolution based on a 3Hz signal. If you query
the range, the multimeter will respond with
"3 Hz"
. Frequency and
period measurements return
"0"
with no input signal applied.
•
The specified range applies to the signal connected to the Input
terminals for ratio measurements. Autoranging is automatically
selected for reference voltage measurements on the Sense terminals.
•
You can set the range using any of the following commands:
CONFigure:<
function
> <
range
>|MIN|MAX|DEF,<
resolution
>|MIN|MAX|DEF
MEASure:<
function
>? <
range
>|MIN|MAX|DEF,<
resolution
>|MIN|MAX|DEF
[SENSe:]<
function
>:RANGe <
range
>|MIN|MAX
[SENSe:]<
function
>:RANGe:AUTO OFF|ON
Summary of Contents for Agilent E1412A
Page 2: ......
Page 10: ...8 Contents Notes...
Page 14: ...12 Notes...
Page 15: ...13 Notes...
Page 16: ...14 Notes...
Page 26: ...24 Agilent E1412A Multimeter Module Setup Chapter 1 Notes...
Page 194: ...192 Agilent E1412A Multimeter Error Messages Appendix B Notes...
Page 201: ...Index 199 Index Agilent E1412A User s Manual and SCPI Programming Guide...
