Agilent Technologies 7890A - To Measure a Detector Flow; Measuring FID, TCD, uECD, and FPD flows

98 Troubleshooting
8 Troubleshooting Tasks
To Measure a Detector Flow
Measuring FID, TCD, uECD, and FPD flows
1 Gather the following:
• Appropriate flowmeter adapter tube (can be found in
the GC ship kit)
• Electronic flowmeter calibrated for the gas and flow
rates of concern
2 Set the oven temperature to ambient (35 °C).
3 Turn off the column flow and pressure.
4 Turn off (where applicable): the FID flame, FPD flame,
and TCD filament.
5 Cool the detector.
6 Connect the appropriate adapter to the detector exhaust.
A rubber adapter tube attaches directly to a uECD, or
TCD exhaust vent.
A separate adapter (19301- 60660) is supplied for the FID.
Insert the adapter into the detector exhaust vent as far as
possible. You will feel resistance as the adapter O- ring is
forced into the detector exhaust vent. Twist and push the
adapter during insertion to ensure a good seal.
WARNING
Hydrogen (H
2
) is flammable and is an explosion hazard when
mixed with air in an enclosed space (for example, a flow meter).
Purge flowmeters with inert gas as needed. Always measure
gases individually. Always turn off detectors to prevent
flame/bead autoignition.
CAUTION
To avoid damaging the column, cool the oven before turning off the
column flow.
NOTE
Flowmeter tube diameters vary by model; modify the adapter to the
flowmeter tubing as needed.