Campbell Scientific UT10 10 foot Tower w/ Grounding Kit and Hinged Base - Manual (Page 59)

UT10 Weather Station
FIGURE 8-32. Declination Angles East of True North are Subtracted
from 0 to get True North
FIGURE 8-33. Declination Angles West of True North are
Added to 0 to get True North
9. Maintenance and Troubleshooting
These guidelines apply to several different Campbell Scientific weather
stations.
9.1 Maintenance
Proper maintenance of weather station components is essential to obtain
accurate data. Equipment must be in good operating condition, which requires
a program of regular inspection and maintenance. Routine and simple
maintenance can be accomplished by the person in charge of the weather
station. More difficult maintenance such as sensor calibration, sensor
performance testing (for example, bearing torque), and sensor component
replacement, generally requires a skilled technician, or that the instrument be
sent to Campbell Scientific or the manufacturer.
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