Send the appropriate command as shown below to your instrument, then read in all the data that is returned.
PZ4000: "NUMERIC:NORMAL:VALUE?"
WT1600: "NUMERIC:NORMAL:VALUE?"
WT100/200 series instruments:
Command type prior to IEEE488.2: "OD"
Command type for IEEE488.2: "MEASURE:NORMAL:VALUE?"
WT1000/2000 series instruments:
Command type prior to IEEE488.2: "OD"
Command type for IEEE488.2: "MEASURE:VALUE?"
Note: If you use pre-IEEE488.2 command types, the measuring instrument will respond to the "OD" command by writing multiple lines including the "END" line, and returning them one by one as they are requested. Therefore after sending the "OD" command, lines must be read out repeatedly until the "END" string is received.
Please refer to the Communications Interface manual for your instrument, for more information about the format of returned data from the various commands.