Empower 3 and Agilent 1260 HPLC Questions

With regards to the lamp: It's clearly the Deuterium (UV) lamp, as your method is using a wavelength of 273nm. The VIS lamp (tungsten) is only used for wavelengths greater than ~500 nm.

I don't know what model of detector you have, but I would suggest to read through the user manual, e.g. for the G7115A https://www.agilent.com/cs/library/usermanuals/public/G7115A_G7165A_User.pdf

Caffeine runs can also be done without a column, just use water at 1ml/min and have a restriction capillary installed. 

Thank you. It is indeed UV lamp. My problem was I set UV LAMP on, but no peaks could be seen in review window. Also, Waters only had lamp on/off option, so I got confused with how UV and VIS lamps work on Agilent. It turned out I was not given correct empower access, so I could not view anything :).  Still, do I need to set a reference wavelength when I check 273nm to be detected?

Thank you. It is indeed UV lamp. My problem was I set UV LAMP on, but no peaks could be seen in review window. Also, Waters only had lamp on/off option, so I got confused with how UV and VIS lamps work on Agilent. It turned out I was not given correct empower access, so I could not view anything :).  Still, do I need to set a reference wavelength when I check 273nm to be detected?

Not necessarily. Try without and if the result is satisfies you, fine. If you have a DAD, you can also go for all spectra at a step size of 1nm and scan e.g. from 210nm to 400nm.