Features and Functions 3
Agilent U1251B/U1252B User’s and Service Guide 55
Null (Relative)
The Null function subtracts a stored value from the present
measurement and displays the difference between the two.
1 Press to store the displayed reading as the
reference value to be subtracted from subsequent
measurements and to set the display to zero. NULL
is displayed.
2 Press to see the stored reference value. NULL
flashes for 3 seconds before the display returns to zero.
3 To exit this mode, press while NULL is flashing on
the display.
• Null can be set for both auto and manual range settings, but not in the
event of an overload.
• When taking a resistance measurement and the meter reads a
non-zero value due to the presence of test leads, use the Null function
to adjust the display to zero.
• When taking a DC voltage measurement, the thermal effect will
influence the accuracy. Short the test leads and press Null once the
displayed value is stable in order to zero out the display.