Detectors
6850
6850
Released: April 2004 6850 Series Gas Chromatograph Service Procedures 177
1. Turn the electrometer off.
2. Turn hydrogen, air, and auxiliary gas supplies
to the detector off. Turn the heaters off.
Wait for the detector to cool.
Caution
Always turn the electrometer off before
removing the PMT housing to avoid destroy-
ing the tube.
3. Release the retaining spring around the pho-
tomultiplier housing.
4. Pull the PMT housing off the detector
module and remove the filter from the detec-
tor. Use lint-free lens tissue to clean the
filter on both sides. Also clean the window in
the PMT tube. Be careful to not scratch the
surfaces; do not use a cleaning fluid that
might leave a film upon drying. Keep the
open end of the PMT covered whenever prac-
tical to avoid light damage to the tube.
Figure 1-17. Removing the PMT filter
Loosen screws
Loosen screw
Filter