Remarks
Use the [SENSe:]CURRent[:DC]:NULL:VALue command to set the null
value.
The CONFigure:CURRent[:DC] and MEASure:CURRent[:DC]? commands
turn off the null state.
A Factory Reset (*RST command) or an Instrument Preset
(SYSTem:PRESet command) returns the null state to off.
