Replacing The Electron Multiplier - Thermo Scientific ISQ 7000 Hardware Manual

Replacing the Electron Multiplier

Thermo Scientific
The lifetime of the electron multiplier is directly related to the current that flows through it
and the amount of contamination or condensation it receives. The electron multiplier will last
longer if you:
• Maintain the best possible vacuum.
• Minimize pump fluid background noise by venting and pumping down less often.
• After pumping down, allow the instrument enough time to equilibrate before you start
running samples again.
• Monitor the GC/MS for background contamination and immediately repair leaks.
• Keep tuning to a minimum.
 To replace the electron multiplier
Note If you just want to replace an individual component of the electron multiplier, see
Replacing Components of the Electron Multiplier
multiplier, refer to the ISQ and TSQ GC-MS Spare Parts Guide.
1. Cool down the GC oven.
2. If you are using hydrogen as a carrier gas, cool down the injector to prepare the GC for
powering off. See the GC documentation for more information. After the heated zones
are cooled down, power-off the GC.
WARNING BURN HAZARD: The injector, oven, and transfer line may be hot. Allow them
to cool to room temperature before touching them.
AVERTISSEMENT RISQUE DE BRÛLURE : l'injecteur, le four et la ligne de transfert
peuvent être chauds. Laissez-les refroidir à la température ambiante avant de les toucher.
WARNING FIRE HAZARD: If you are using hydrogen as a carrier gas, you must cool down
and shut off the GC to prevent the buildup of hydrogen in the vacuum manifold. See the
"Hydrogen Safety Precautions"
AVERTISSEMENT RISQUE D'INCENDIE : si vous utilisez de l'hydrogène comme gaz vecteur,
vous devez refroidir et mettre hors tension le CG pour éviter l'accumulation d'hydrogène
dans le collecteur à vide. Reportez-vous aux « Précautions de sécurité relatives à
l'hydrogène » à la page xvi de la préface pour plus d'informations.
for details. To order a new electron
on page xvi of the Preface for more information.
1
Performing Routine Maintenance
Replacing the Electron Multiplier
ISQ 7000 Hardware Manual 99