Agilent Technologies 6890 Series Service Manual page 356

Photomultiplier tube
Figure 350-11
3. Slide the resistor network cable assembly and the photomultiplier tube
and socket out of the housing until about 1 inch of the tube is exposed.
4. Pull the socket off the PMT. Remove the PMT and replace with a new tube.
5. When seating the socket on the new tube, be certain that the missing pin
on the tube base is lined up with the gap in the socket contacts.
6. Reassemble in the reverse order. Make sure grease, fingerprints, dust,
etc. are removed from the PMT window facing the detector module. Be
sure that the O-ring is in place on the PMT/resistor bridge network
assembly, as this is a critical light seal. If the O-ring is lost or damaged,
replace it.
7. Screw the end cap onto the PMT assembly. Pull the cables through the
cable tie to eliminate slack at the end of the assembly. Place the cables
in the clip on the side of the PMT housing support.
Jun 2001
FPD Photomultiplier Tube (PMT) Replacement
Detectors
Agilent 6890 Gas Chromatograph Service Manual
Flame Photometric Detector (FPD)
Replacement procedures
Resistor network
cable assembly
Tube socket
PMT tube housing
350
End cap
19 of 36