Keithley 6482, Справочное руководство

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17-10 Return to Section Topics 6482-901-01 Rev. A / August 2012
Section 17: Calibration Model 6482 Dual-Channel Picoammeter / Voltage Source Reference Manual
Analog output accuracy
Follow the steps below to verify that Model 6482 analog output voltage accuracy is within specified
limits. This test involves applying currents from a Model 6430 and verifying that the 20 mA range
analog output voltage readings are within required limits.
CAUTION With the ground connect mode enabled, analog output LO can float up to
±30 V above chassis ground, depending on the voltage bias source setting.
Connecting the analog outputs to external equipment that does not allow
analog output low to float up to ±30 V may result in damage to the Model 6482
voltage bias sources when the ground connect mode is enabled.
1. With the power off, connect the Model 6430 to the channel 1 INPUT triaxial connector through
the preamp (using the Mainframe/preamp cable and a triaxial cable), and connect the DMM to
the channel 1 ANALOG OUT connector, as shown in
Figure 17-5 .
2. Turn on the Model 6482, Model 6430, and the Model 2001 DMM. Allow them to warm up for at
least one hour.
3. Restore front-panel bench defaults, as outlined in Restoring factory defaults .
4. On the Model 6482, press the MSR1 key, and then select the 2 nA range on channel 1 by
pressing the RANGE key as needed.
5. Select the Model 6430 amperes function and choose the 2 nA range.
6. Set the Model 6430 output to 1.90000 nA and turn the output on.
7. Verify that the analog output voltage reading, as measured by the DMM, is within the limits for
the 2 nA range shown in Table 17-4 .
8. Repeat steps 4 through 7 for the 20 nA through 20 mA ranges.
9. Repeat steps 4 through 8 for negative input currents of the same magnitude. Analog output
voltages will be positive with negative input currents.
10. After verifying all ranges on channel 1:
a. With the power off, make connections to the channel 2 (see Figure 17-6 for connec-
tions).
b. Repeat steps 3 through 9 verifying the acurracy of channel 2 (press the MSR2 key to
select channel 2).
Table 17-4
Model 6482 analog output verification limits
Model 6482
range
Model 6430 current
Analog output voltage limits*
1 year, 18° C to 28° C (65° F to 82° F)
2 nA
20 nA
200 nA
2 µA
20 µA
200 µA
2 mA
20 mA
1.90000 nA
19.0000 nA
190.000 nA
1.90000 µA
19.0000 µA
190.000 µA
1.90000 mA
19.0000 mA -8.840 V to -10.160 V
-9.206 V to -9.794 V
-8.840 V to -10.160 V
-9.206 V to -9.794 V
-8.840 V to -10.160 V
-9.254 V to -9.747 V
-8.840 V to -10.160 V
-9.254 V to -9.747 V
*Limits do not include Model 6430 or DMM uncertainty.