Waters 2998, Обзор и руководство по обслуживанию

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December 5, 2017, 715004753 Rev. B
Page 53
4
Diagnostic Tests and
Troubleshooting
Consult this chapter when troubleshooting problems with the 2998 PDA detector. Bear in
mind, however, that the detector measures only the bulk properties of a system. Therefore,
the cause of an apparent detector problem can originate with the chromatography or other
system instruments.
4.1 Diagnostic tests
The detector automatically runs a series of internal diagnostic tests upon start up. The indicator
LEDs on the front of the detector and messages at the chromatographic data software workstation
show the test result.
If you must determine the cause of a problem while the detector is operating, you can run the
same internal diagnostic tests from the chromatographic data software workstation. Additional
information about the performance of the detector is also available through the PDA Console,
accessed from chromatographic data software
.
4.1.1 Verifying the detector calibration
Verify the detector calibration after removing and replacing a flow cell. Before you power-on the
detector, prime the system to fill the flow cell with solvent and remove any air. To ensure that the
detector is properly aligned and calibrated, fill the flow cell with solvent before you power-on the
detector. An empty flow cell causes a calibration error.
Recommendation:
Impurities in the flow cell can affect wavelength verification results. Ensure
that the flow cell is clean before you calibrate.
To verify detector calibration:
1. Select a solvent compatible with the samples and mobile phases that you have been using.
Requirement:
If you have been using buffers, flush the detector with 10 mL of HPLC-grade
water followed by 10 mL of a low-surface-tension solvent such as methanol. The solvent
must be miscible with the previous mobile phase.
2. In the console, select 2998 PDA Detector from the system tree.
3. In the PDA detector information window, click Maintain > Verify calibration > Start.
Result:
The test time appears in the Run Time bar graph.
4. Verify that the detector passed the test by reviewing the test results in the Results pane.
Rule:
The maximum deviation must be within

/

nm of the standard calibration.
Tip:
If the test returns a failing result, flush the flow cell, and perform this procedure again.