Keithley 2750, Service Manual

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2-14 Calibration Model 2750 Multimeter/Switch System Service Manual
Remote calibration
Follow the steps in this section to perform comprehensive procedures via remote. See
Appendix B for a detailed list and description of remote calibration commands.
When sending calibration commands, be sure that the Model 2750 completes each step
before sending the next command. You can do so either by observing the front panel CAL-
IBRATING message, or by detecting the completion of each step over the bus. (See
Appendix B , “ Detecting calibration step completion .”)
The procedures for calibrating the Model 2750 via remote include:
• Preparing the Model 2750 for calibration
• Front panel short and open calibration
• DC volts calibration
• Resistance calibration
• DC current calibration
• AC volts calibration
• AC current calibration
• Programming calibration dates
• Saving calibration constants
• Locking out calibration
NOTE As with front panel calibration, you can choose to perform comprehensive, DC-
only, or AC-only calibration. Be sure to include a space character between each
command and parameter.
Preparing the Model 2750 for calibration
1. Connect the Model 2750 to the IEEE-488 bus of the computer using a shielded
IEEE-488 cable, such as the Keithley Model 7007, or connect the unit to a com-
puter through the RS-232 port using a straight-through 9-pin to 9-pin cable (use a
9-25-pin adapter if necessary).
2. Turn on the Model 2750, and allow it to warm up for at least two hours before per-
forming calibration.
3. Make sure the primary address of the Model 2750 is the same as the address speci-
fied in the program that you will be using to send commands. (Use the GPIB key.)
4. Unlock the calibration function by sending this command:
:CAL:PROT:CODE 'KI002750'
(The above command shows the default code, KI002750. Substitute the correct
code if changed.)
5. Send the following command to initiate calibration:
:CAL:PROT:INIT