Galvanic Applied Sciences 943-TGS, Operation Manual

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Revision 1 86 6/27/2017
7.6 Cell Windows Replacement
Under normal operating conditions, cell window replacement is necessary only when the
particular window becomes cracked, chipped, etched or stained to a non-cleanable degree.
Changing the cell windows is most easily accomplished by removing the entire measurement
cell assembly from the oven compartment. It is recommended that the measurement cell
assembly is opened in a clean environment such as a bench top.
Procedure:
a) Remove the cell as described in Section 7.5.
The oven compartment and all of its components are HOT (50ºC/120ºF).
Wear appropriate personal protective equipment (gloves, eye wear,
clothing etc) if working with hot surfaces or wait until surface have cooled
to safe temperatures before performing maintenance tasks.
The sample system must be back purged with zero gas prior to
disconnecting any fittings to ensure that the toxic sample gases are swept
clean from the system. The sample inlet and vent block valves must be
closed.
b) With the measurement cell in a vertical position, remove the top cell end cap (large four
(4) sided nut). Leave the SMA fibre connector in place in the cell end cap body.
c) Remove the top O-ring. If it is not on the cell window then it will be in the end cap O-ring
groove. Discard if there is any sign of damage or deformation.
d) Turn the measurement cell over, holding your hand over the open end, and gently shake
until the cell window drops into your hand. Set the window aside on a clean surface.
Remove the bottom O-Ring (if it didn’t drop into your hand with the window). A fine tipped
tool may be required. Discard the O-ring if there is any sign of damage or deformation.
e) Repeat steps a) through d) to remove the other cell window.
f) Inspect both windows for damage and/or contaminants. If the windows are damaged
(chipped, cracked, etc.) discard and replace them with new ones. If the windows are not
damaged, they should be cleaned with isopropyl alcohol, using a non-abrasive lint free
tissue such as KimWipes
®
or a cotton swab. Thoroughly rinse the cleaned surface with
pharmaceutical grade distilled water. They should be wiped dry using a soft, lint free cloth
or tissue.
Commercially available lens or window cleaning solutions or prepackaged
lens cleaning wipes ARE NOT to be used. These products may contain a
compound which leaves an UV absorbing coating on the optical
component.