Command
:SENSe<Ch>:CORRection:COLLect:ACQuire:LOAD
This command measures the load data for the user calibration.
In the user calibration, the :SENS:CORR:COLL:SAVE should be executed after open/short/load calibrations.
Ana.WriteString ":SENS1:CORR1:COLL:ACQ:LOAD", True
Cal > User Cal > Execute Cal > Load
SCPI.SENSE(Ch).CORRECTION.COLLECT.ACQUIRE.LOAD