Campbell Scientific Wireless Sensor Network (CWB100, CWS220, and CWS900) - Manual (Page 48)

Wireless Sensor Network
Prior to sensor discovery, the numeric monitor will display the name of the
public variable specified in the CWB100 instruction with NAN as the
output. Once the sensor has been discovered, NAN will change to
Undefined.
To view the user-specified Field Names in the numeric monitor, delete the
original Public variables from the display with the Delete All button and
add the Public table again with the Add button. Now the correct Field
Names will be displayed for each sensor with their real-time values.
7. Maintenance
Minimal maintenance is required for the CWS900, CWS220, and CWS655
wireless sensors. If batteries are solar charged, the solar cell battery lid needs
to be periodically cleaned with water to remove dust and debris. Alkaline
batteries need to be replaced periodically as needed. It is good practice to store
the battery voltage of individual sensors in the datalogger to determine when
the sensor power supply needs attention.
It is important to keep the lens and view of the CWS200 clean. Otherwise the
sensor will be measuring the temperature of the obstruction instead of the
surface of interest. Clean the lens gently with a moistened cotton swab.
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