User manual

8-2 Relative and Math 2400 Series SourceMeter
®
User’s Manual
Relative
The rel (relative) feature can be used to null offsets or subtract a baseline reading
from present and future readings. With REL enabled, subsequent readings will be
the difference between the actual input value and the rel value as follows:
Displayed Reading = Actual Input - Rel Value
Once a rel value is established for a measurement function, the value is the same
for all ranges. For example, if 5V is set as a rel value on the 20V range, the rel
value is also 5V on the 2V and 200mV ranges.
Selecting a range that cannot accommodate the rel value does not cause an over-
flow condition, but it also does not increase the maximum allowable input for that
range. For example, on 20V range, the SourceMeter still overflows for a >21.1V
input.
NOTE When rel is enabled, the REL annunciator turns on. Changing measure-
ment functions disables rel.
Front panel rel
Enabling and disabling rel
Rel can be used to null out zero offsets or to establish a zero baseline by pressing
the REL key. The reading (which becomes the rel value) is subtracted from itself.
As a result, a zero reading is displayed. Pressing REL a second time disables rel.
Defining a rel value
A unique rel value can be established for the selected measurement function from
the front panel as follows:
1. Press CONFIG and then REL. The present rel value will be displayed.
2. Set the desired rel value. (See Section 1, “Rules to navigate menus,” for
details.)
3. With the desired rel value displayed, press ENTER. The SourceMeter will
return to the normal source-measure display with rel enabled. The reading
will reflect the defined rel value.