Rosemount Analytical NGA 2000, Руководство пользователя

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M
AINTENANCE AND
T
ROUBLESHOOTING
4-8
June 1997 Rosemount Analytical 748332-D NGA 2000 Non-Dispersive Infrared Analyzer
4.12 CLEANING CELLS
1. When zero gas is introduced in the SAMPLE IN inlet and the Detector signal is
greater 1.2V, the cells and windows require cleaning. To do this, follow this
procedure:
2. See Figure 4-7 to identify which detail drawing best matches the configuration in
question.
3. Fold out the PCB panel.
4. Disassemble the optical bench according to Figure 4-4 and the cells according to
Figure 4-7.
5. Rinse the cell with acetone. If this does not remove all foreign matter, use a soft
brush. Do not use any metallic object inside the cell because it will scratch the gold
plating. Loss of gold plating may require cell replacement.
6. After all matter has been removed, rinse the cell with distilled water and allow to air
dry. Do not use towels.
7. Inspect the cell inside by holding it up to a bright light. If particles are seen, repeat
Steps 5 and 6 as often as necessary.
8. After cleaning cell, examine O-rings at the source, detector and end caps. If
damaged, replace with new O-rings.
9. Remove any contaminants from windows with a lint-free cloth soaked in acetone.
Do not use alcohol or other solvents. Allow to air dry.
10. Reverse disassemble instructions to reassemble the unit.
11. Perform a leak check.
12. Replace desiccant if required. (See Section 4.13.)
13. After cleaning cells, the Analyzer Module must be optically aligned if the diagnostic
values for oscillator tune and detector signals are not within
±
5% of the factory
settings (see Figure 3-13, in Primary Variable Parameters and Modulation Check
menus). If they are not within that range, follow Steps 7 through 10 of Section 4.11.