Agilent Technologies 5975

Operating in Chemical Ionization (CI) Mode 4
5975 Series MSD Operation Manual for MassHunter 131
amiliarize yourself with the measurements on your system under operating
conditions and watch for changes that may indicate a vacuum or gas flow
problem. Measurements will vary by as much as 30% from one MSD and gauge
controller to the next.
Table 20 Flow and pressure readings
Pressure (Torr)
Methane Ammonia
MFC
(%)
EI/PCI/NCI MSD
(Performance turbo pump)
EI/PCI/NCI MSD
(Performance turbo pump)
10 5.5
×10
–5
5.0 ×10
–5
15 8.0 ×10
–5
7.0 ×10
–5
20 1.0 ×10
–4
8.5 ×10
–5
25 1.2 ×10
–4
1.0 ×10
–4
30 1.5 ×1
–4
1.2 ×10
–4
35 2.0 ×10
–4
1.5 ×10
–4
40 2.5 ×10
–4
2.0 ×10
–4