3
Vacuum System
Vacuum Gauges
Thermo Scientific
TSQ Altis, Quantis, and Fortis Hardware Manual
13
Vacuum Gauges
Three types of vacuum gauges measure the pressure in specific regions of the vacuum
manifold. In the Tune application, you can observe the readback values for the vacuum gauges
on the By Function page in the Status pane (under Vacuum).
• Convection pressure gauge—Measures pressure down to a fraction of a milliTorr (mT).
The instrument uses two convection gauges:
–
Source pressure gauge—Measures the pressure in the RF lens and
region in the vacuum manifold and the foreline, which connects the triple-inlet
turbomolecular pump and the forepump or forepumps.
–
Collision gas pressure gauge—Measures the pressure in the collision cell.
• Ionization gauge—Measures the pressure in the analyzer region of the vacuum manifold.
The ionization gauge produces energetic electrons that cause molecular ionization. A
collector attracts positive ions formed in the ionization gauge, and the collector current is
related to the pressure in the vacuum manifold. The ionization gauge is also involved in
vacuum protection.
