7. Check the connections of the deflector cage for deformation or contamination.
– Contamination may not be immediately evident and can only be identified as a result of poor
performance.
8. Check the electrical connections of the quadrupole mass filter for correct connection.
9. Check the high-frequency connections for correct connection.
9.3.2 Baking out the analyzer
WARNING
Risk of burns during baking out
During or immediately after the baking out, the heating jacket and the metal surfaces near to the
heating jacket are extremely hot. The metal surfaces can reach a temperature of over 100 °C. This
causes burns if you do not wear suitable personal protective equipment.
► When baking out, always wear personal protective equipment (for example protective gloves).
► Never touch surfaces without suitable protective gloves, either during or directly after baking out.
NOTICE
Damage to the electronic unit (QME) caused by baking out
Excessively high temperatures damage the electronic unit.
► Dismantle the electronic unit from the analyzer (Q&A) before baking out at temperatures >
200°C.
NOTICE
Damage to the electron multiplier (EM) caused by excessive temperatures
Switching on the electron multiplier at high temperatures will lead to permanent damage.
► Do not switch on the electron multiplier at analyzer temperatures > 150 °C.
Prerequisites
● Vacuum system with heater for baking out the analyzer
● Temperature which can be attained with the heater > 120 °C.
● High vacuum > 1 × 10
-5
hPa
Detector type
In operation
QME removed
Faraday
200 °C
300 °C
Faraday/EM combination
EM mode
150 °C
300 °C
Faraday mode
200 °C
300 °C
Tbl. 13:
Maximum bakeout temperatures
Baking out the analyzer
1. Attempt to restore the normal performance by baking out the analyzer under a high vacuum for
several hours - at best overnight.
2. Check the filaments and the ion source if the desired result is not accomplished by baking out the
analyzer.
3. Contact
if you cannot resolve the existing problem by doing so.
9.4 Replace filament unit
Visual inspection before replacing the filament unit
Inspect and assess the complete ion source before replacing the filament unit. Pfeiffer Vac-
uum recommends replacing the complete ion source in the event of damage, significant de-
posits or soiling as well as signs of contamination (e.g. discoloration).
Maintenance
47/86
