I'm guessing that you are using the comma (,) as a "decimal separator", i.e. 28,30 means 28-and-30-hundredths (what I would write as 28.30, as I use a period instead of a comma).
By default, LabVIEW should use whatever your PC uses as the default, so the string "28,30 28.30" read with format "%f %f" should give you "28,30" and "28", that is, a 4-digit floating decimal number and a two-digit number, with the period signalling to LabVIEW to stop scanning because a non-floating-point-character (the period) was encountered.
You can set the comma or period (or set "use what the PC uses") by putting the Format code %,; (use comma), %.; (use period, or %; (use system default). Thus if you wanted to read "28,30 28.30" as two floats, and you knew the first used a comma, the second a period, you would specify "%,;%f %.;%f" (you specify the separator before specifying that you want to parse a Float).
You can find this yourself by reading the Help for "Scan from String" and then clicking on the "format string" link in the Help text.
Bob Schor
