Keithley 2500, Руководство по обслуживанию

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Model 2500 Service Manual Calibration 2-17
Step 6. Channel 2 current calibration
Follow the steps below to calibrate all channel 2 current ranges. Table 2-5 summarizes cal-
ibration ranges and currents.
1. Connect the calibrator to the Model 2500 INPUT CHANNEL 2 jack, as shown in
Figure 2-4 .
2. Select the calibrator passive V/R amps function. Set the calibrator output to
+1.90000nA, and turn on the output.
3. Press the Model 2500 MSR2 key, then set channel 2 to the 2nA current range using
the RANGE
key.
4. Press the MENU key, select CAL, then press ENTER.
5. Select EXECUTE, then press ENTER to enter the CAL EXECUTION menu.
6. Select I-CAL then press ENTER. The unit will display the following:
I -CAL CHANNEL SELECT
CHAN-1 CHAN-2
7. Select CHAN-2 then press ENTER. The instrument will prompt for the positive
full-range current:
I (+FS)
2
= +2.000000nA
Use , , , , ENTER or EXIT.
8. Set the calibrator current to +1.90000nA.
9. Use the EDIT keys to adjust the Model 2500 display value to agree with the cali-
brator current.
10. Press ENTER. The unit will prompt for the zero current:
I (0)
2
= +0.000000nA
Use , , , , ENTER or EXIT.
11. Set the calibrator current to 0nA then press ENTER. The instrument will prompt
for the negative full-range current:
I(-FS)
2
= -2.000000nA
Use , , , , ENTER or EXIT.
12. Set the calibrator current to -1.90000nA.
13. Adjust the displayed current to agree with the calibrator current, then press the
Model 2500 ENTER key to complete calibration of the present range.
14. Press EXIT to return to normal display.
15. Repeat steps 3 through 14 for the 20nA to 20mA ranges, using Table 2-5 as a
guide. Be sure to set the Model 2500 to the correct range using the RANGE and
keys, and use the corresponding calibrator currents for each range.