How do I lower my signal in my DAD detector in my Agilent 1260 HPLC system?

I am setting up our new HPLC for preparative scale separation.

Currently, I am saturating the UV-detector (the peaks in the chromotagram are cut-off at the top). 

How do I lower signal intensity? I tried changing the attenuation value but this had no effect on the signal intensity. 

I apologize if this is a trivial issue. 



Was this helpful?