Campbell IRGASON, Product Manual, Page: 38 / 91

The wicks are constructed with a UV-resistant fabric and should function over long time periods.
Nevertheless, they should be inspected periodically. Check for contamination from dust, pollen,
pitch or other debris. If needed, wash them in warm water with mild detergent or replace them.
When performing the zero-and-span procedure, the wicks should be removed before installing
the zero-and-span shroud.
Remove the wicks during the winter. The wicks will accumulate snow or freezing rain, resulting in
blockage of the optical path. Besides the wicks, controlling the heaters in the snouts is another
method the user may consider in preventing data loss during precipitation and condensation
events. The heaters can be controlled statically using the Setup window in
ECMon or dynamically
using a data logger (see EC100Configure() instruction (p. 49) for more details).
FIGURE 9-3. Proper location of the gas analyzer top wick (left) and bottom wick (right)
9.3 Gas analyzer window cleaning
The windows of the analyzer should be cleaned if the signal strength for CO
2
or H
2
O drops below
0.7 or 70% of the original value. These values may be monitored in the output data, or they can
be viewed with
ECMon . To clean the windows, use isopropyl alcohol (2-propanol/isopropanol)
and a cotton swab or a non-scratching tissue or cloth. Verify that following cleaning the signal
strengths are restored to values close to 1.0.
9.4 Zero and span
As is the case with all optical instruments, the IRGASON gas analyzer measurements may drift
slightly with exposure to natural elements. Therefore, routine maintenance requires a periodic
zero-and-span procedure. The frequency with which this should be done is heavily dependent
IRGASON® Integrated CO
2
/H
2
O Open-Path Gas Analyzer and 3D Sonic Anemometer 34