Keithley 2601B Reference Manual page 780

Appendix B: Calibration
G. Send the contact check high calibration command:
smua.contact.calibratehi(r0_hi, Z_actual, r50_hi, 50_ohm_actual)
Where:
r0_hi
Z_actual
r50_hi
50_ohm_actual = Actual 50 Ω resistor value; the value of the resistor between the SENSE HI and
Typical values:
smua.contact.calibratehi(r0_hi, 0, r50_hi, 50.15)
Where r0_hi is the same value as measured in step B, and r50_hi is the same value as
measured in step E.
Step 5. Program calibration dates
Use the following command to set the calibration adjustment date:
smua.cal.adjustdate = os.time{year=2010, month=12, day=1}
Optionally, it is possible to set the calibration date and calibration due date with the following
commands:
smua.cal.date = os.time{year=2010, month=12, day=1}
smua.cal.due = os.time{year=2011, month=12, day=1}
If you do not wish to set a calibration date or calibration due date and want to clear the previous
values, use the following commands:
smua.cal.date = 0
smua.cal.due = 0
The actual year, month, day, and (optional) hour and minute should be used (seconds can be given
but are essentially ignored due to the precision of the internal date storage format). The allowable
range for the year is from 1970 to 2037, the month is from 1 to 12, and the day is from 1 to 31.
Step 7. Save calibration constants
Calibration adjustment is now complete, so you can store the calibration constants in nonvolatile
memory by sending the following command:
smua.cal.save()
Unless you send the save command, the calibration adjustment you just performed will be
temporary.
Step 8. Lock out calibration
To lock out further calibration, send the following command after completing the calibration
procedure:
smua.cal.lock()
B-38
Series 2600B System SourceMeter® Instrument Reference Manual
= Series 2600B 0 Ω high measurement
= Actual zero value; the resistance of the short between the SENSE HI and HI
terminals
= Series 2600B 50 Ω high measurement
HI terminals
2600BS-901-01 Rev. B / May 2013