Getting an exact RGB value

Just make sure that desired base colors are more more saturated than the measured values.
Example: With an ISO of 100 R G B
    Measured: 128 128 128
    Desired 255 255 255
    WB= 128 128 128 (Same as measured)
    New ISO= 199.2188
    Makes sense?

For all colors less saturated, the WB=measured Colors and leave the ISO alone; I think…, maybe not!

Is auto white balance in V-Ray 6 do all this job automatically?