Keithley SourceMeter 2425, Service Manual

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2-8 Calibration Model 2425 Service Manual
Resetting the calibration password
If you lose the calibration password, you can unlock calibration by shorting together the
CAL pads, which are located on the display board. Doing so will also reset the password
to the factory default (KI002425).
See Section 5 for details on disassembling the unit to access the CAL pads. Refer to the
display board component layout drawing at the end of Section 6 for the location of the
CAL pads.
Viewing calibration dates and calibration count
When calibration is locked, only the UNLOCK and VIEW-DATES selections will be
accessible in the calibration menu. To view calibration dates and calibration count at any
time:
1. From normal display, press MENU, select CAL, and then press ENTER. The unit
will display the following:
CALIBRATION
UNLOCK EXECUTE VIEW-DATES
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2. Select VIEW-DATES, then press ENTER. The Model 2425 will display the next
and last calibration dates and the calibration count as in the following example:
NEXT CAL: 12/15/1999
Last calibration: 12/15/1999 Count: 0001
Calibration errors
The Model 2425 checks for errors after each calibration step, minimizing the possibility
that improper calibration may occur due to operator error.
Front panel error reporting
If an error is detected during comprehensive calibration, the instrument will display an
appropriate error message (see Appendix B). The unit will then prompt you to repeat the
calibration step that caused the error.