Keithley 2701, Service Manual

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Model 2701 Service Manual Performance Verification 1-7
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 2701 to be on an incorrect range. For each test signal, you must manu-
ally set the correct range for the Model 2701 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.
WARNING Observe the following safety precautions when performing these tests:
• Some of the procedures in this section may expose you to dangerous
voltages. Use standard safety precautions when such dangerous
voltages are encountered to avoid personal injury or death caused by
electric shock.
• For the front panel terminals only, the maximum common-mode volt-
age (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 plug-in modules, the maximum common-mode voltage (volt-
age 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.