When exposed to sunlight, the 108 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 colo
u
r of these shields reflects solar radiation, and the louvred construction allows air
to pass freely through, thereby keeping the probe at or near ambient temperature. The RAD06
uses a double-louvred 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 108 and 41303-5A Radiation Shield on a CM200-Series Crossarm
108 Temperature Probe
8
