Keithley 2750, Service Manual

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2-6 Calibration Model 2750 Multimeter/Switch System Service Manual
Aborting calibration
You can abort the front panel calibration process at any time by pressing EXIT. The instru-
ment will then ask you to confirm your decision to abort with the following message:
ABORT CAL?
Press EXIT to abort calibration at this point, or press any other key to return to the calibra-
tion process.
NOTE The Model 2750 will not respond to any remote programming commands while
the ABORT CAL? message is displayed.
Front panel calibration
Follow the steps in the following paragraphs in the order shown for comprehensive, DC
only, and AC only calibration procedures.
The procedures for front panel calibration include:
• Preparing the Model 2750 for calibration
• Front panel short and open calibration
• DC voltage calibration
• Resistance calibration
• DC current calibration
• AC voltage calibration
• AC current calibration
• Setting calibration dates
Preparing the Model 2750 for calibration
1. Turn on the Model 2750, and allow it to warm up for at least two hours before per-
forming a calibration procedure.
2. Start the calibration process as follows:
a. Access the calibration menu by pressing SHIFT then TEST, then display
TEST: CALIB using the up or down range key. Press ENTER.
b. Use the up or down range key to scroll through the available calibration menu
items until the unit displays RUN, then press ENTER.
c. At the prompt, enter the calibration code. (The default code is 002750.) Use
the left and right arrow keys to move among the digits; use the up range key to
increment numbers, and press the down range key to specify alphabetic letters.
Confirm the code by pressing ENTER.
d. Choose N at the prompt to proceed without changing the code, then press
ENTER.