2 Replies Latest reply on Dec 5, 2018 7:03 AM by spacefish

    G4212B drift

    sheydashakiba

      We have a problem with baseline drift (sometimes constant increase, sometimes constant decrease) after the lamp has already been warmed up several hours. Our lamp tag shows only 1600 hours burn time (minimum 200 h lifetime). We wanted to try checking for a loose optical cable following pg. 115 (Figure 33) of the manual (G4212-90013) but can't figure out what part is being shown in the diagram or how to access it. Could you provide extra guidance or troubleshooting information? Thanks.

        • Re: G4212B drift
          jhagel

          I'm sorry we cannot help diagnose under the covers for safety reasons.  Have you run DAD tests from lab advisor?  Is the temperature in the lab stable? what happens to the baseline if you stop the flow?

          You may want to cal your local Agilent office

          • Re: G4212B drift
            spacefish

            Depends on the amplitude of the drift. Some drift is expected, the specification lists < 0.5 × 10-3 AU/hr at 230 nm for the 4nm slit.

            Drift can be caused by changing thermal conditions

            - AC cycling

            - Changing sunlight through a window

            - Changing airflow due to open doors / weather outside

            - Changing temperature of solvents due to pump head warmup after start of flow

             

            There is a test called "ASTM Drift and Noise Test" in Lab Advisor which checks if the drift is in normal limits.

            You can get the latest version of Lab Advisor here: http://labadvisor.pl29.agilent.com/latest