330 Thermal Conductivity Detector (TCD)
Replacement procedures
12 of 24
Jun 2001
Detectors
Agilent 6890 Gas Chromatograph Service Manual
6. Install the new cell and reassemble the detector. Reassembly is the
reverse of removal with the following additional considerations:
• Before replacing the insulation, place the cap that came with your
detector over the detector vent to prevent plugging the vent with
insulation. Remove the cap once the insulation is in place.
7. When replacing the detector cover, make sure that the hole in the top of
the cover is positioned over the detector vent and that the filaments,
plumbing and heater/sensor leads including the ∆PRT leads, if used on
the TCD) are positioned under the appropriate cut-outs on the sides of
the cover.
• Make sure that only the filament wire is inserted into the connector,
not the insulation sleeve. Then, check the filaments by tugging
slightly on them.
• If your TCD uses a ∆PRT, check the sensor lead connections to the
detector card by tugging slightly on them.
• Replace the heater/sensor and ∆PRT. In the sensor holes as shown
below.
Caution If your detector card uses a ∆PRT, make sure the ∆PRT leads are properly
installed. If the ∆PRT leads are not properly installed in the detector card,
filament burnout can occur.