Lutron Electronics FG-6020SD Operation Manual page 19

2) If the first time to execute the Datalogger,
under the route FGB01\, will generate a new
file name FGB01001.XLS.
After exist the Datalogger, then execute again,
the data will save to the FGB01001.XLS until
Data column reach to 30,000 columns, then
will generate a new file, for example FGB01002.XLS
3) Under the folder FGB01\, if the total files more
than 99 files, will generate anew route, such as
FGB02\ ........
4) The file's route structure :
FGB01\
FGB01001.XLS
FGB01002.XLS
.....................
FGB01099.XLS
FGB02\
FGB02001.XLS
FGB02002.XLS
.....................
FGB02099.XLS
FGBXX\
.....................
.....................
Remark :
XX : Max. value is 10.
16