Keithley SourceMeter 3A 2420 Service Manual page 41

2. From normal display, press the SOURCE I key.
3. Press the EDIT key to select the source display field, and then use the down RANGE key
to select the 10µA source range.
4. From normal display, press MENU.
5. Select CAL, and then press ENTER. The unit will display the following:
CALIBRATION
UNLOCK EXECUTE VIEW-DATES
SAVE LOCK CHANGE-PASSWORD
6. Select EXECUTE, and then press ENTER. The instrument will display the following message:
I-CAL
Press ENTER to Output +10.000
7. Press ENTER. The Model 2420 will source +10µA and simultaneously display the fol-
lowing:
DMM RDG: +10.00000µA
Use ENTER, or EXIT.
, , , ,
8. Note and record the DMM reading, and then adjust the Model 2420 display to agree
exactly with the actual DMM reading. Use the up and down arrow keys to select the digit
value, and use the left and right arrow keys to choose the digit position (or use the number
keys, 0-9, +/-). Note that the display adjustment range is within ±10% of the present range.
9. After adjusting the display to agree with the DMM reading, press ENTER. The instru-
ment will then display the following:
I-CAL
Press ENTER to Output +00.000µA
10. Press ENTER. The Model 2420 will source 0mA and at the same time display the following:
DMM RDG: +00.00000µA
ENTER
Use
, , , ,
11. Note and record the DMM reading, and then adjust the Model 2420 display to agree with
the actual DMM reading. Note that the display value adjustment limits are within ±1%
of the present range.
12. After adjusting the display value to agree with the DMM reading, press ENTER. The
unit will then display the following:
I-CAL
Press ENTER to Output -10.000µA
13. Press ENTER. The Model 2420 will source -10µA and display the following:
DMM RDG: -10.00000µA
Use , , , , ENTER, or EXIT.
14. Note and record the DMM reading, and then adjust the Model 2420 display to agree with
the DMM reading. Again, the maximum display adjustment is within ± 10% of the
present range.
15. After adjusting the display value to agree with the DMM reading, press ENTER and note
that the instrument displays:
I-CAL
Press ENTER to Output -00.000µA
µ
A
, or EXIT.
Calibration 2-11