Keithley 6482, Справочное руководство

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6482-901-01 Rev. A / August 2012 Return to Section Topics 17-3
Model 6482 Dual-Channel Picoammeter / Voltage Source Reference Manual Section 17: Calibration
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 rear panel
line frequency setting) and a line frequency of 50 Hz or 60 Hz. Verification tests must be performed
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 .
Recommended test equipment
Table 17-1 summarizes recommended verification equipment and pertinent specifications. Total
test equipment measurement uncertainty should meet or be less than the listed values at each test
point. Generally, test equipment uncertainty should be at least four times better than
corresponding Model 6482 specifications.
NOTE The sources listed in Table 17-1 do not meet the recommended four times better
uncertainty for certain output values. Factory calibration uses a transfer standard
technique that yields uncertainties better that 4:1 for all calibration points.
Table 17-1
Recommended verification equipment
Description Manufacturer/model Specifications
Uncertainty
ratio
2
Meter/Source Keithley Instruments
Model 6430
Sub-Femtoamp
Remote SourceMeter
®
instrument with preamp
DC current 1.9 nA:
19 nA:
190 nA:
1.9
μ
A:
±0.155 %
±0.155 %
±0.208 %
±0.155 % 7.1:1
2.6:1
2:1
1.4:1
Calibrator Fluke 5700A
Multifunction Calibrator DC current 19
μ
A:
190
μ
A:
1.9 mA:
19 mA:
±0.059 %
±0.011 %
±0.007 %
±0.007 % 3.5:1
9.8:1
31:1
17:1
Digital multimeter Keithley Instruments
Model 2001 DC voltage
1
20 V:
200 V: ±22 ppm
±30 ppm 45:1
33:1
1
90-day full-range accuracy specifications.
2
Ratio between test equipment uncertainty and Model 6482 uncertainty.