LI-COR LI7200RS, Инструкция по эксплуатации

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Section 5. Maintenance
Once per week:
After installing the new system, start by checking the signal strength once per
week. There is no absolute guideline for good or bad signal strength, but 100%
indicates very clean optics and optimal performance from the analyzer. If the signal
strength has dropped, it is a good idea to clean the optics. For most sites, the main-
tenance frequency is once every 3-4 weeks. The signal strength limit, below which
the instrument readings are compromised, varies due to the spectral characteristics
of the contaminants involved. Typically, signal strength values should be main-
tained in the upper 90’s for consistent performance. Delta signal strength is a vari-
able that provides an indication of the drift associated with contamination. See
CO2
Signal Strength on page 8-7 for more information.
Once per month:
Check the zero and span. As you become familiar with your instrument, you will
probably find that this does not need to be checked as often.
If you are not using an intake filter, clean the upper and lower windows of the ana-
lyzer (see
Cleaning the Optical Path on the facing page).
Download all your data and store it to an archive.
Check cables for damage. Tighten any loose cable connections.
Check tubing for kinks or damage (both the pressure and flow tubes). If either
tube is restricted, either replace it or reposition it so that the flow does not become
restricted.
Every six months:
If your instrument is in a humid environment, replace the head chemicals.
Once per year:
Replace the head chemicals.
Clean or replace any air filters.
Every two years:
Check the instrument calibration with one or more span gases. If it is outside the
specifications, return the instrument to LI-COR for recalibration.
5-2 LI-7200RS Enclosed CO₂/H₂O Analyzer