LI-COR LI-7500, Instruction Manual

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Maintenance 5-1
Maintenance
Cleaning the Optical Path
The LI-7500 optical windows should be cleaned when necessary (when the AGC value
approaches 100%). If the windows become dirty it may become difficult to calibrate the
analyzer. Excessive zero drift may also be observed if the optical path becomes obstructed.
The windows are sapphire, and are extremely durable and resistant to scratches; clean the
windows with any mild detergent or glass cleaner. Also, coating the windows with a water
resistant windshield type coating (such as Rain-X
®
) or a high quality automobile type wax
may help prevent droplets from remaining on the windows during rainstorms. Mounting the
sensor head at a slight angle from vertical (~10-15°) may also help prevent water droplets
from remaining on the windows during rainstorms.