varian lamp

[moon704520]

hi, I have been using varian 320 uv/vis detector for two years ,yet ,gradully I find that ,the up limit of the absorb value often changs greatly when I change the wave length,and sometims the up limit changes even though I did northing with the detector,i really do not know why is so ?

[Chris0000]

Hi

I hope I can help you, there are several possible issues:

First the 320 Detector is running a calibration procedure if you switch it on.
In order to have a good calibration, it is recommended to rinse the flow cell 5 minutes before switching the 320 on ( just start the pumps a little earlier)
This should remove air or sample in the flowcell that might effect the calibration.

Second: There might be some dirt in the flowcell, we did talk about this before, espacially the dual-path cells ( like 9-1 or 4,5-0,15) are sensitive to this issue.
If you have a dual cell, there should be a x on the display

Third: The autorange function might be a possibility, too. You can switch it off
in "setup" --> "integrator/recorder"

Regards Chris