Npd Required Gas Purity - Agilent Technologies 7820A Advanced User's Manual

150
100
Flow, mL/min
50
Pressure (psig)
(
kPa)
5
4
3
Flow, mL/min
2
1
Pressure (psig)
(
kPa)

NPD required gas purity

Advanced User Guide
10 20 30
69 138 207
4 8
28 55
Temperature programming
The NPD is flow sensitive. If you are using temperature
programming, in which the column flow resistance changes
with temperature, set up the instrument as follows:
• Set the carrier gas in the Constant flow mode. Set detector
makeup gas to Constant makeup.
• If you choose to work in the constant pressure mode, the
makeup gas should be set in the Column +makeup=constant
mode.
Because of its high sensitivity, the NPD requires very pure (at
least 99.9995%) gases. We strongly recommend that moisture
and organics traps be used on the carrier gas and all detector
Air
Helium
Nitrogen
40 50 60
276 345 414
Hydrogen
12 16
83 110
Detectors
70
483
20
138
5
87