Page 116
IR Cell Cleaning
UVTOCMaintenance.fm
Section 7
Figure 38 Installing a Pump
7.6 IR Cell Cleaning
If relay contacts are connected to ac line voltage, remotely disconnect
the power before opening the analyzer’s upper enclosure door. See
Safety Note 7.1 on page 111 before performing this procedure.
The IR cell assembly cleaning interval is application dependent. Minimally,
it should be cleaned once a year. If analysis results become unstable, it may
be an indication that the IR cell needs cleaning. For the purposes of clarity,
the accompanying illustrations show the IR cell removed from the analyzer.
Required cleaning materials:
• Isopropyl alcohol (clean water is also effective)
• Lint-free cleaning tissues
• Long cotton swabs
• Cutting pliers (to cut the tie wrap holding the thumb latch to allow the
cell assembly to be removed from the IR bench).
1. Refer to Figure 39 on page 117 and remove the inlet and outlet tubing
from the IR cell.
2. Support the mirror assembly (to prevent the cell assembly from falling out
if the thumb latch unexpectedly releases) and cut the tie wrap.
3. Release the thumb latch by pulling it away from the cell assembly.
4. Clean the interior wall of the cell assembly with lint-free cleaning tissues
and isopropyl alcohol, as shown in See Safety Note 40 on page 118.
5. Use cotton swabs and isopropyl alcohol to clean the sapphire window that
protects the parabolic mirror, as shown in Figure 41 on page 118.
6. Inspect the assembly to make certain that all debris and contamination
are fully removed and that the sapphire is free of scratches and cracks.