Keithley 2790, Reference Manual

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Model 2790 SourceMeter
®
Switch System Reference Manual 4-3
Manual ranging
To change range, press the RANGE or key. The instrument changes one range per
key press. The selected range is displayed for one second. Note that the manual range keys
have no effect on temperature (TEMP).
If the instrument displays the “OVERFLOW” message on a particular range, select a
higher range until an on-range reading is displayed. Use the lowest range possible without
causing an overflow to assure best accuracy and resolution.
Auto ranging
To enable auto range, press the AUTO key. The AUTO annunciator turns on when auto
ranging is selected. While auto ranging is enabled, the instrument automatically selects the
best range to measure the applied signal. Auto ranging should not be used when optimum
speed is required. Note that the AUTO key has no effect on temperature (TEMP).
Up-ranging occurs at 120% of range. The Model 2790 will down-range when the reading
is <10% of nominal range.
To disable auto ranging, press AUTO. This will leave the instrument on the present range.
You can also disable auto ranging by pressing the
or key, however a range change
may occur.
Scanning (7702 only)
When a simple scan using the 7702 module is configured, the present function and range
setting will apply to all channels in the scan. When an advanced scan is configured, each
channel can have its own unique range setting. Details to configure and run a scan are pro-
vided in
Section 7 .
For remote programming, the <clist> parameter is used to configure channels for a scan.