1. IntroductionThe UT20 and UT30 are durable, lightweight instrument towers used for a variety of applications.They support a 6 m (20 ft) or 9 m (30 ft) measurement height for wind sensors as well as sturdyattachment points for antennas, solar panels, environmental enclosures, radiation shields, andcrossarms. A retractable mast at the top of the tower adds increased flexibility in the placement ofsensors at the top of the tower.NOTE:Throughout the manual, the term "tower" refers to both the UT20 and UT30, unless specifiedotherwise.2. Precautions2.1 Site selectionl Select a safe site to install the tower.l The distance between any power lines and the installation site should be at least one andone-half times the height of the tower. Make the distance even greater, if possible. Sinceall overhead lines look somewhat alike, consider them all dangerous and stay well awayfrom them.l If there are power lines or buried utilities in the area, call the local utility providers forassistance.2.2 Tower mountingl NEVER work alone; always have someone near who can summon help.l Certain clothing may provide a degree of safety, but do not depend on it alone to preservelife (for example, rubber boots or shoes, industrial rubber gloves, or a long shirt or jacket).l Check local weather conditions. Be sure it has not rained recently, and the ground is notwet or muddy. Make sure rain or thunderstorms are not predicted for the day the tower isto be installed.UT20 and UT30 Universal Towers 1