When exposed to sunlight, the 109 should be housed in a six-plate solar radiation shield. Six-
plate shields offered by Campbell Scientific are models 41303-5A, 41303-5B, or RAD06.
The white color of these shields reflects solar radiation, and the louvered construction allows air
to pass freely through, thereby keeping the probe at or near ambient temperature. The RAD06
uses a double-louvered design that offers improved sensor protection from insect intrusion and
driving rain and snow. In addition, the RAD06 shield has lower self-heating in bright sunlight
combined with higher temperatures (> 24 °C (75 °F)) and low wind speeds (< 2 m/s (4.5 mph)),
giving a better measurement.
The 41303-5A and RAD06 attach to a crossarm, mast, or user-supplied pipe with a 2.5 to 5.3 cm
(1.0 to 2.1 in) outer diameter. The 41303-5B attaches to a CM500-series pole or a user-supplied
pole with a 5.1 cm (2.4 in) outer diameter.
Tools required for installing a radiation shield to a tripod or tower include:
l
1/2-inch open end wrench
l
UV resistant cable ties
l
adjustable wrench with a minimum 1-1/2 inch jaw size
FIGURE 7-1. Installing a 109 and 41303-5A Radiation Shield on a CM200-Series Crossarm
109 Temperature Probe
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