Yes, that was the problem. #-o
Thankyou.
Now, I understand that where it puts 200 I have to set the max mv. And the 0 is the place for decimals.
If it is correct, then I have to tick “Use this value” and “Calculate % from raw compared to max”. But I have to leave not ticked “Plot this %” of the Labjack. Is this right? :o
Thanks again. 
Finally I have the solar sensor working properly. 
After being calibrated, I have compared the readings with another weather station and the readings are quite the same. 
As I have said:
I am doing a Pre-University research project about Sun that will punctuate me for the access to the university; and one part of this project will be record data of the solar radiation in my city. But it do not have to be very accurate.
So, is there some way to save the data recorded with WD?
I have seen that in “Advanced Graph” you can save the graphs of the last hours.
But I wonder if there is some other way apart from this to do that.
In summary: What are the possible methods to save the data acquired by the sensor? :?:
Hi
there is a logfile, vantagelog.txt
thats has the solar wm/2 in it
or you can create your own logfile, using custom tags (e.g for solar, time, date, etc)
I am also new here and I had same question. Now, after reading other people replies few of my doubts are cleared.