Thermo Scientific TSQ Altis, Руководство по оборудованию

Страница: 62 / 176

12
Maintaining the MS on a Daily Basis
Before Operating the Mass Spectrometer
44 TSQ Altis, Quantis, and Fortis Hardware Manual Thermo Scientific
4. Check each fitting and flange on the system for tightness and tighten any that are loose.
Start with fittings that have been changed recently and fittings that have been subjected to
heating and cooling.
Checking the Vacuum Pressure Levels
You can check the current values of the pressures in the ion transfer tube-RF lens and foreline
(labeled
Source Pressure ) and in the analyzer region (labeled Analyzer Pressure ) in the Status
pane of the Tune window.
1. Open the Tune window.
2. Click the Status tab and click the Expand icon, , next to Vacuum.
3. Compare the current values of the pressures in the vacuum manifold with the values listed
in Table 6 for the TSQ Altis MS, Table 7 for the TSQ Quantis, and Table 8 for the
TSQ Fortis MS. If the values are higher than normal, you might have an air leak.
CAUTION For proper performance, operate the system at the proper vacuum levels. Poor
vacuum levels can cause reduced sensitivity and reduced electron multiplier life.
Table 6. TSQ Altis typical pressure readings
Pressure (Torr)
Conditions Source Pressure
(foreline, ion transfer
tube, RF lens region) Analyzer
(analyzer region after
pumping for at least 12
hours)
Collision gas off, ion transfer
tube orifice sealed Less than 0.05 Less than 6 × 10
–
6
Collision gas off, ion transfer
tube orifice open Less than 2.0 Less than 9 × 10
–
6
Collision gas set to 1.5 mTorr,
ion transfer tube orifice open Less than 2.0 Approximately 3 × 10
–
5