Chromatography Forum

Hi, I have a problem with my dad detector in shimadzu HPLC. First of all after returning from holidays my baseline is drifting, it's one tendency - decreasing, the slopeof this decrease is rather high - about 20 Absorbancy units in 10 minutes. In the same time baseline is noisy (8Abs up and down). We ahve changed lately the lamp and the cell (before holidays), but everything was fine. I have tryied to do lamp enery test, but takes about 30 minutes, and if I want stop it by myself - it will never end. After I stop test - there are no results in the window. I tried also to do wavelength accuracy test - it failed. The difference in proper wavelength are between 2-10nm. Therefore I tried to do calibration but I can't. There is comment that I should call for a service. Has someone any idea what can be the cause of those problems? may it be the problem of lamps?
Thanks for any advices.

Failing wavelength accuracy and not completing the energy measurement are consistent with several causes:
- a lamp problem (possibly misaligned?)
- a power supply problem
- an electronic problem

Lamp re-installation is a do-it-yourself item, the other two are probably best done by a trained service tech.

If manually tweaking the alignments of both the lamp and the mirror (goal: to get similarly high numbers for both reference and sample energy) does not help, I'd call for help as you've probably got other issues. This advice is based on the assumptions that 1) the new lamp is good and 2) the m10AVP lamp compartment resembles that of the SPD10A and other Shimadzu detectors.