Varian 450-GC, User Manual

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Pulsed Flame Photometric Detector (PFPD) - Detectors
Varian, Inc. User Manual 450-GC Page: 369
Suggested Fuel Gas Flow Rates
The following table lists flow rates f or several carrier gases that are often used
in common analysis situations when operating the PFPD. Use these flow rates
as starting points when optimizing the performance of the PFPD.
Carrier Gas Flow Rate
(mL/min)
H
2
(mL/min)
Ai r1
(mL/min)
Ai r2
(mL/min)
Helium
2 13 17 10
5 13 20 10
10 20 34 10
Hydrogen
2 11 17 10
5 9 18 10
10 15 31 10
Nitrogen
2 14 17 10
5 16 21 10
10 24 34 10
Table 57: Flow Rates PFPD
You May Not Need to Adjust Flow Rates
The difference in optimum gas flow rates between sulfur and phosphorus is
small. If you don’t require the maximum sensitivity for an analysis, leave the
flow rates as they are and change only the optical filter, gate delay and
integration time, when shifting between the sulfur and phosphorus detection
modes.