Campbell LWS, Инструкция по эксплуатации

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LWS Dielectric Leaf Wetness Sensor
1. Introduction
Direct measurement of leaf wetness is problematic. Secure long-term
attachment of a sensor to a representative living leaf is difficult. Leaf position,
sun exposure, and health are in constant flux. To avoid these problems, leaf
wetness sensors have been developed to estimate by inference the wetness of
nearby leaves. The LWS estimates leaf surface wetness by measuring the
dielectric constant of the sensor’s upper surface. The sensor is able to detect
the presence of miniscule amounts of water or ice. Individual sensor
calibration is not normally necessary.
This manual provides information only for CRBasic dataloggers.
It is also compatible with most of our retired Edlog dataloggers.
For Edlog datalogger support, see an older manual at
www.campbellsci.com/old-manuals or contact a Campbell
Scientific application engineer for assistance.
2. Cautionary Statements
• READ AND UNDERSTAND the Precautions section at the front of this
manual.
• Care should be taken when opening the shipping package to not damage or
cut the cable jacket. If damage to the cable is suspected, consult with a
Campbell Scientific application engineer.
•
Although the LWS is rugged, it should be handled as a precision scientific
instrument.
• Over time, the accumulation of dust and bird droppings can cause the dry
output to rise. We recommend that the sensor be periodically cleaned
using a moist cloth, or when you detect elevated dry output.
• The LWS is intended only for applications wherein the datalogger
provides short excitation, leaving the probe quiescent most of the time.
Continuous excitation may cause the probe to exceed government
specified limits on electromagnetic emissions.
3. Initial Inspection
• Upon receipt of the LWS, inspect the packaging and contents for damage.
File damage claims with the shipping company.
•
The model number and cable length are printed on a label at the
connection end of the cable. Check this information against the shipping
documents to ensure the correct product and cable length are received.
NOTE
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