HP 34401A, User Manual

Page: 39 / 236

To Make Null (Relative) Measurements
Each null measurement, also called relative, is the difference between a
stored null value and the input signal.
Result = reading – null value
•
You can make null measurements with any function except
continuity, diode, or ratio. The null operation is local to the selected
function; when you change functions, null is disabled.
•
To null the test lead resistance for more accurate two-wire ohms
measurements, short the ends of the test leads together and then
press
Null
.
•
The first reading taken after you press
Null
is stored as the null
value in the Null Register. Any previously stored value is
replaced with the new value.
•
After enabling null, you can edit the stored null value by
pressing
Shift >
(Menu Recall). This takes you to the
“
NULL VALUE
” command in the
MATH MENU
( only if null is
enabled ). Go down to the “parameter” level, and then edit the
displayed value.
•
The null register is cleared when you change functions, turn null off,
turn off the power, or perform a remote interface reset.
Enables null operation;
Press again to disable. Math annunciator is on when
null operation is enabled.
To read / edit the null value, use the MATH menu.
Chapter 2 Front-Panel Menu Operation
To Make Null (Relative) Measurements
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