Waters 2998, Обзор и руководство по обслуживанию

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December 5, 2017, 715004753 Rev. B
Page 56
4.1.6 Changing the rear-panel interface connections
Via the rear panel display, you can open and close certain output connections. Opening or closing
output connections can be useful when you need to troubleshoot system connectivity.
To change 2998 PDA detector rear panel interface connections:
1. In the console, select 2998 PDA Detector from the system tree.
2. In the PDA detector information window, click Troubleshoot > Rear Panel.
3. Click the broken connection symbol , to close the connection, and thus turn the LED from
red to green and vice versa as necessary.
Restriction:
In the PDA Detector Rear Panel dialog box, only the switch 1 and switch 2
outputs can be modified.
4.2 General troubleshooting
This section suggests possible causes of errors and recommends troubleshooting actions. Keep in
mind that the source of apparent detector problems can actually be the chromatography, or it can
involve other system components.
Most detector problems are relatively easy to correct. If, after running the diagnostic functions
applicable to your problem and troubleshooting the detector, you cannot correct an error condition,
contact Waters’ Technical Service department.
4.2.1 Troubleshooting lamps
Air bubbles in the flow cell or incorrect installation of the lamp can cause an apparent lamp-related
problem. Before replacing the lamp, ensure that the detector cell is filled with solvent and that it is
free of air bubbles, and that the current lamp is installed correctly.
If you have not operated the detector for 2000 hours or more, flushing the flow cell can sometimes
correct an apparent problem of low lamp intensity.
Mobile phase absorbance affects apparent lamp intensity. For example, water or acetonitrile is
more transparent than methanol at wavelengths below 220 nm.
4.2.2 Power surges
Power surges, line spikes, and transient energy sources can adversely affect detector operation.
Ensure that the electrical supply used for the detector is properly grounded and free from any of
these conditions.
4.2.2.1 Power LED
The power LED, on the detector’s front door, indicates when the instrument is powered-on or
powered-off. It is constant green when the instrument is working properly.