Keithley 2790, Reference Manual

Page: 388 / 568

Model 2790 SourceMeter
®
Switch System Reference Manual 16-7
Test considerations
When performing the verification procedures:
• Be sure to restore factory defaults as outlined above.
• Make sure that the equipment is properly warmed up and connected to the correct
input terminals. Also, make sure that the INPUTS switch is in the correct position.
• Do not use autoranging for any verification tests because autorange hysteresis may
cause the Model 2790 to be on an incorrect range. For each test signal, you must
manually set the correct range for the Model 2790 using the range keys.
• Make sure the calibrator is in operate before you verify each measurement.
• Always let the source signal settle before taking a reading.
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Observe the following safety precautions when performing these tests:
√
Some of the procedures in this section may expose you to danger-
ous voltages. Use standard safety precautions when such danger-
ous voltages are encountered to avoid personal injury or death
caused by electric shock.
√
For the front panel terminals only, the maximum common-mode
voltage (voltage between INPUT LO and chassis ground) is 500V
peak. Exceeding this value may cause a breakdown in insulation,
creating a shock hazard.
√
For the Model 7702 module, the maximum common-mode voltage
(voltage between any plug-in module terminal and chassis ground)
is 300V DC or 300V RMS. Exceeding this value may cause a
breakdown in insulation, creating a shock hazard.
√
When using the front panel terminals simultaneously with plug-in
modules, all cable insulation voltage ratings must equal or exceed
the maximum voltage applied to either the front panel terminals or
the plug-in module terminals.