Campbell Scientific EC150 CO2 and H2O Open-Path Gas Analyzer and EC100 Electronics with Optional CSAT3A 3D Sonic Anemometer - Manual (Page 40)

EC150 CO
2
/H
2
O Open-Path Gas Analyzer
Performing frequent zero-and-span procedures when the instrument is first put
into use to determine the drift from factory calibration, will give a good
guideline for the frequency that the procedure should be performed.
To perform a maintenance zero and span, follow the same steps as in Section 7,
Zero and Span.
8.5 Replacing CO
2
Scrubber Bottles
If more than one year has passed since replacing the desiccant/scrubber or if
the zero-and-span readings have drifted excessively (see Section 7, Zero and
Span), the desiccant/scrubber bottles within the EC150 analyzer head should be
replaced. FIGURE 8-2 gives the details needed for the following steps.
The scrubber bottles contain strong oxidizing agents. Avoid
direct contact with the chemicals inside the bottles. Also
ensure your work area is well ventilated and free of any
reactive compounds, including liquid water. Store used
chemical bottles in a sealed container until disposal.
Replacing Scrubber Bottles
1. Twist the scrubber bottle covers of the upper and lower arms counter
clockwise until they detach (they should loosen by hand).
2. Remove the EC150 chemical bottles (pn 26510) from inside the
covers, and replace them with new bottles with the lid of the bottle
pointing toward the snouts of the analyzer (see FIGURE 8-2).
Before opening the covers, have the chemical bottles ready so that
the time the internal volume of the analyzer is exposed to the
environment is minimized.
3. Screw the covers back on the arms. Do not over tighten.
4. Allow the sensor to equilibrate for at least 24 hours (longer if in high
humidity).
5. After 24 hours, perform a zero-and-span procedure. If readings
continue to be suspect, the sensor may need to be recalibrated at the
factory (see Section 8.6, Factory Recalibration, below).
The chemical bottles should be disposed of according to local and federal
regulations. For more information, Material Safety Data Sheet (MSDS) forms
for the chemicals are included in Appendix E, Material Safety Data Sheets
(MSDS).
DANGER
NOTE
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