Agilent Technologies G7035A Operation Manual page 65

The largest influence on operating pressure in EI mode is the carrier gas
(column) flow.
flows. These pressures are approximate and will vary from instrument to
instrument by as much as 30%.
Table 13
Column flow rate,
mL/min
0.5
0.7
1
1.2
2
3
4
6
If the pressure is consistently higher than those listed, refer to the online help
in the MassHunter Data Acquisition software for information on
troubleshooting air leaks and other vacuum problems.
In the Instrument Control view you can set up an MS Monitor for displaying this
vacuum reading. The vacuum can also be read on the LCP or from the Manual
Tune screen.
5977 Series MSD Operation Manual
Table 13 lists typical pressures for various helium carrier gas
Ion vacuum gauge reading
Optional Gauge
reading, Torr
Performance turbo
pump
3.18E–06
4.42E–06
6.26E–06
7.33E–06
1.24E–05
1.86E–05
2.48E–05
3.75E–05
Operating in Electron Ionization (EI) Mode
Gauge reading, Torr
Diffusion pump
2.18E–05
2.59E–05
3.66E–05
4.46E–05
7.33E–05
1.13E–04
3
Foreline reading, Torr
Diffusion pump
34.7
39.4
52.86
60.866
91.784
125.76
65