Campbell UT20, Product Manual

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the chance of shading from other weather station structures. Reflective surfaces and sources of
artificial radiation must be avoided.
Heated pyranometers, such as the SP230-L from Campbell Scientific, are available for use in areas
where snow, frost, or dew may accumulate.
The height the sensor is mounted is not critical.
4.5 Soil temperature
Prepare a site for soil temperature measurements at least 1 m2 and typical of the surface of
interest. The ground surface must be level to the immediate area (10 m radius).
Standard measurement depths:
l
10 cm ± 1.0 cm (AASC)
l
5.0 cm, 10.0 cm, 50.0 cm, 100.0 cm (WMO)
4.6 Siting references
1
EPA, (2000). Meteorological Monitoring Guidance for Regulatory Modeling Applications, DPA-
454/R-99-005. Office of Air Quality Planning and Standards, Research Triangle park, NC. 27711
2
WMO, (2008 edition, updated in 2010). Guide to Meteorological Instruments and Methods of
observation. World Meteorological Organization No 8, 2008 edition, Geneva Switzerland.
3
The State Climatologist, (1985). Publication of the American Association of State Climatologists:
Height and Exposure Standards for Sensors on Automated Weather Stations, v. 9, No. 4, October
1985.
5. Overview
The UT20 and UT30 towers provide a versatile mount for sensors, antennas, solar panels,
environmental enclosures, radiation shields, and mounting crossarms. Its 6 m (20 ft) or 9 m (30 ft)
height allows for wind measurements at those levels.
The main tower frame ( FIGURE 5-1 (p. 7)) is built from 2.5 cm (1 in) OD (outside diameter)
corrosion-resistant aluminum tubing. It includes an adjustable mast, a hinged base, anchor bolts,
lightning rod, ground rod, and cable tie kit.
Enclosures purchased for use with this tower must be ordered with the tower mount option. This
provides the necessary bracketing to mount the enclosure to the tower.
UT20 and UT30 Universal Towers 6