Keithley 6482, Справочное руководство

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6482-901-01 Rev. A / August 2012 Return to Section Topics 17-13
Model 6482 Dual-Channel Picoammeter / Voltage Source Reference Manual Section 17: Calibration
Adjustment
Use the procedures in this section to calibrate the Model 6482. These procedures require accurate
test equipment to supply precise currents and measure accurate DC voltages. Calibration can be
performed either from the front-panel or by sending SCPI calibration commands over the IEEE-
488 bus or RS-232 port, with the aid of a computer.
WARNING The information in this section is intended for qualified service personnel
only. Do not attempt these procedures unless you are qualified to do so. Some
of these procedures may expose you to hazardous voltages.
Environmental conditions
Temperature and relative humidity
Conduct the calibration procedures at an ambient temperature of 18 °C to 28 °C (65 °F to 82 °F),
with relative humidity of less than 70 percent (unless otherwise noted).
NOTE Product specifications that are listed as 18 ºC to 28 ºC assume adjustment has been
done at 23 ºC. If the Model 6482 is adjusted at a different temperature, the specifications
apply to ±5 ºC of that adjustment temperature.
Warm-up period
Allow the Model 6482 to warm up for at least one hour before conducting the verification
procedures.
If the instrument has been subjected to temperature extremes (those outside the ranges stated
above), allow additional time for the instrument’s internal temperature to stabilize. Typically, allow
one extra hour to stabilize an instrument that is 10 °C (18 °F) outside the specified temperature
range.
Allow the test equipment to warm up for the minimum time specified by the manufacturer.
Line power
The Model 6482 requires a line voltage of 100 V, 120 V, 200 V, or 240 V (depending on line voltage
setting) at a line frequency of 50 Hz or 60 Hz. The instrument must be calibrated while operating
from a line voltage within this range. Make sure the line voltage setting, that is visible through the
small window in the rear-panel power module, is at the required setting. If not, change the setting,
as described in
Section 18 .
Adjustment considerations
When performing the adjustment procedures:
• Make sure the test equipment is properly warmed up and connected to the Model 6482
input or output terminals, as required.
• Allow signals to settle before calibrating each point.
• Do not connect test equipment to the Model 6482 through a scanner or other switching
equipment.
• If an error occurs during calibration, the Model 6482 will generate an error message. See
Appendix A for more information.