Hardware manual

4-92 Agilent 7500 Series ICP-MS Hardware Manual
4Maintenance
The Agilent 7500cs or 7500cx Main Lens assembly consists of 2 ion lens
assemblies: the Extraction Lens- Omega Lens assembly and the Reaction Cell
assembly. The Extraction Lens- Omega Lens assembly consists of the
Extraction Lens and the Omega Lens. The Extraction Lens- Omega Lens and
Reaction Cell assemblies can be cleaned separately. The ion lenses must be
reassembled in their original configuration after cleaning. Make sure the
workspace is free of contamination and large enough to lay out the dismantled
components in order.
It is necessary to open the vacuum chamber to clean the Reaction cell. Refer to
the procedure “Working Inside the Vacuum Chamber” on page 4- 77 for an
explanation of the correct method for this procedure.
In addition to the recommended cleaning frequency in the maintenance
schedule, the lenses should be cleaned if any of the following symptoms are
observed:
• The signal is unstable. For example, more than 10% signal drift in an hour.
This may also be caused by other parts such as sample introduction.
• The lens voltage is changed in the MassHunter Workstation (or
ChemStation) software, and the resulting signal changes very slowly. For
example, if you change the parameters drastically step by step, it will take
more than 1 second for the signal to stabilize.
• When changing the parameters during tuning, the response speed of the
signal is different when changing the value from the plus direction and
changing it from the minus direction.
It is necessary to clean the Octopole if there is a signal drift, or a longer than
normal period of time is required for the signal to stabilize when switching
from hydrogen to standard mode.
To minimize maintenance time, clean the Reaction cell first. While cleaning
the cell, replace the chamber cover and start the pumps. After cleaning,
reassemble and install the reaction cell assembly, clean the Extraction
Lens- Omega Lens assembly.
CAUTION
Before opening the vacuum chamber to clean the Reaction cell or for other purposes,
always switch off the power to the Agilent 7500.