Flame Photometric Detector; Cleaning/Replacing Fpd Windows, Filters, Seals - HP 5890 Series II Plus Reference Manual

Preventive Maintenance

Flame photometric detector

Caution Failure to turn off the TCD and to cap the detector column fitting may
cause irreparable damage to the filament due to O
detector.
3. Establish normal reference gas flow rate (20 to 30 ml/min) through
the detector (set oven temperature to 250 C).
4. Heat the detector to 400 C; allow thermal cleaning to continue for
several hours.
Flame photometric detector

Cleaning/replacing FPD windows, filters, seals

Column bleed and/or effluent can contaminate the first quartz window
(heat shield) nearest the detector module. Dust, fingerprints, atmospheric
contaminants can dirty both quartz windows, the filter, and/or the
photomultiplier tube (PMT) window. Contamination anywhere along the
light path between flame and PMT can reduce detector sensitivity.
Turn the detector off.
Turn off hydrogen, air (or oxygen), and auxiliary nitrogen supplies to the
detector (manifold on•offvalves); for convenience, carrier flow and other
temperature zones may be left on and at their respective setpoints. Allow
time for the detector module to cool.
Remove the PMT assembly from the detector module and remove the
filter. Use lint•freelens tissue to clean the filter (both sides) carefully, and
the PMT window seen inside the housing. Be careful not to scratch
surfaces; do not use any cleaning fluid that might leave a film upon
drying.
Inspect the filter; chips, scratches, and/or cracks in the light path scatter
light, reducing detector sensitivity. Replace filter(s) as necessary (sulfur
mode filter, Part No. 19256•80000;phosphorus mode filter, Part No.
19256•80010).
entering the
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