User`s guide

Remarks
This command affects both 2-wire and 4-wire resistance measurements. All
FRES and RES commands affect the equivalent settings for all resistance
measurements.
Use the [SENSe:]FRESistance:NULL:VALue command to set the null value.
The CONFigure:FRESistance and MEASure:FRESistance? commands turn
off the null state.
A Factory Reset (*RST command) or an Instrument Preset
(SYSTem:PRESet command) returns the null state to off.