Campbell UT20 User manual

UT20 and
UT30
Universal Towers
Revision: 8/18
Copyright ©
1993 – 2018
Campbell Scientific, Inc.

Limited Warranty
“Products manufactured by CSI are warranted by CSI to be free from defects in
materials and workmanship under normal use and service for twelve months
from the date of shipment unless otherwise specified in the corresponding
product manual. (Product manuals are available for review online at
www.campbellsci.com.) Products not manufactured by CSI, but that are resold
by CSI, are warranted only to the limits extended by the original manufacturer.
Batteries, fine-wire thermocouples, desiccant, and other consumables have no
warranty. CSI’s obligation under this warranty is limited to repairing or
replacing (at CSI’s option) defective Products, which shall be the sole and
exclusive remedy under this warranty. The Customer assumes all costs of
removing, reinstalling, and shipping defective Products to CSI. CSI will return
such Products by surface carrier prepaid within the continental United States of
America. To all other locations, CSI will return such Products best way CIP
(port of entry) per Incoterms ® 2010. This warranty shall not apply to any
Products which have been subjected to modification, misuse, neglect, improper
service, accidents of nature, or shipping damage. This warranty is in lieu of all
other warranties, expressed or implied. The warranty for installation services
performed by CSI such as programming to customer specifications, electrical
connections to Products manufactured by CSI, and Product specific training, is
part of CSI's product warranty. CSI EXPRESSLY DISCLAIMS AND
EXCLUDES ANY IMPLIED WARRANTIES OF MERCHANTABILITY
OR FITNESS FOR A PARTICULAR PURPOSE. CSI hereby disclaims,
to the fullest extent allowed by applicable law, any and all warranties and
conditions with respect to the Products, whether express, implied or
statutory, other than those expressly provided herein.”

Assistance
Products may not be returned without prior authorization. The following
contact information is for US and international customers residing in countries
served by Campbell Scientific, Inc. directly. Affiliate companies handle repairs
for customers within their territories. Please visit www.campbellsci.com to
determine which Campbell Scientific company serves your country.
To obtain a Returned Materials Authorization (RMA) number, contact
CAMPBELL SCIENTIFIC, INC., phone [phone]. Please write the
issued RMA number clearly on the outside of the shipping container. Campbell
Scientific’s shipping address is:
CAMPBELL SCIENTIFIC, INC.
RMA#_____
815 West 1800 North
Logan, Utah 84321-1784
For all returns, the customer must fill out a “Statement of Product Cleanliness
and Decontamination” form and comply with the requirements specified in it.
The form is available from our website at www.campbellsci.com/repair. A
completed form must be either emailed to [e-mail] or faxed to
[phone]. Campbell Scientific is unable to process any returns until we
receive this form. If the form is not received within three days of product
receipt or is incomplete, the product will be returned to the customer at the
customer’s expense. Campbell Scientific reserves the right to refuse service on
products that were exposed to contaminants that may cause health or safety
concerns for our employees.

Safety
DANGER — MANY HAZARDS ARE ASSOCIATED WITH INSTALLING, USING, MAINTAINING, AND WORKING ON OR AROUND
TRIPODS, TOWERS, AND ANY ATTACHMENTS TO TRIPODS AND TOWERS SUCH AS SENSORS, CROSSARMS, ENCLOSURES,
ANTENNAS, ETC. FAILURE TO PROPERLY AND COMPLETELY ASSEMBLE, INSTALL, OPERATE, USE, AND MAINTAIN TRIPODS,
TOWERS, AND ATTACHMENTS, AND FAILURE TO HEED WARNINGS, INCREASES THE RISK OF DEATH, ACCIDENT, SERIOUS
INJURY, PROPERTY DAMAGE, AND PRODUCT FAILURE. TAKE ALL REASONABLE PRECAUTIONS TO AVOID THESE HAZARDS.
CHECK WITH YOUR ORGANIZATION'S SAFETY COORDINATOR (OR POLICY) FOR PROCEDURES AND REQUIRED PROTECTIVE
EQUIPMENT PRIOR TO PERFORMING ANY WORK.
Use tripods, towers, and attachments to tripods and towers only for purposes for which they are designed. Do not exceed design limits.
Be familiar and comply with all instructions provided in product manuals. Manuals are available at www.campbellsci.com or by
telephoning [phone] (USA). You are responsible for conformance with governing codes and regulations, including safety
regulations, and the integrity and location of structures or land to which towers, tripods, and any attachments are attached. Installation
sites should be evaluated and approved by a qualified engineer. If questions or concerns arise regarding installation, use, or
maintenance of tripods, towers, attachments, or electrical connections, consult with a licensed and qualified engineer or electrician.
General
•Prior to performing site or installation work, obtain required approvals and permits. Comply
with all governing structure-height regulations, such as those of the FAA in the USA.
•Use only qualified personnel for installation, use, and maintenance of tripods and towers, and
any attachments to tripods and towers. The use of licensed and qualified contractors is highly
recommended.
•Read all applicable instructions carefully and understand procedures thoroughly before
beginning work.
•Wear a hardhat and eye protection, and take other appropriate safety precautions while
working on or around tripods and towers.
•Do not climb tripods or towers at any time, and prohibit climbing by other persons. Take
reasonable precautions to secure tripod and tower sites from trespassers.
•Use only manufacturer recommended parts, materials, and tools.
Utility and Electrical
•You can be killed or sustain serious bodily injury if the tripod, tower, or attachments you are
installing, constructing, using, or maintaining, or a tool, stake, or anchor, come in contact with
overhead or underground utility lines.
•Maintain a distance of at least one-and-one-half times structure height, 20 feet, or the distance
required by applicable law, whichever is greater, between overhead utility lines and the
structure (tripod, tower, attachments, or tools).
•Prior to performing site or installation work, inform all utility companies and have all
underground utilities marked.
•Comply with all electrical codes. Electrical equipment and related grounding devices should be
installed by a licensed and qualified electrician.
Elevated Work and Weather
•Exercise extreme caution when performing elevated work.
•Use appropriate equipment and safety practices.
•During installation and maintenance, keep tower and tripod sites clear of un-trained or non-
essential personnel. Take precautions to prevent elevated tools and objects from dropping.
•Do not perform any work in inclement weather, including wind, rain, snow, lightning, etc.
Maintenance
•Periodically (at least yearly) check for wear and damage, including corrosion, stress cracks,
frayed cables, loose cable clamps, cable tightness, etc. and take necessary corrective actions.
•Periodically (at least yearly) check electrical ground connections.
WHILE EVERY ATTEMPT IS MADE TO EMBODY THE HIGHEST DEGREE OF SAFETY IN ALL CAMPBELL SCIENTIFIC PRODUCTS,
THE CUSTOMER ASSUMES ALL RISK FROM ANY INJURY RESULTING FROM IMPROPER INSTALLATION, USE, OR
MAINTENANCE OF TRIPODS, TOWERS, OR ATTACHMENTS TO TRIPODS AND TOWERS SUCH AS SENSORS, CROSSARMS,
ENCLOSURES, ANTENNAS, ETC.

i
Table of Contents
PDF viewers: These page numbers refer to the printed version of this document. Use the
PDF reader bookmarks tab for links to specific sections.
1. Introduction ................................................................1
2. Precautions ................................................................1
2.1 Site Selection .......................................................................................1
2.2 Tower Mounting ..................................................................................1
2.3 Tower Installation ................................................................................1
3. Initial Inspection.........................................................2
3.1 Indoors .................................................................................................2
3.2 Outdoors...............................................................................................2
3.3 Tools Required.....................................................................................2
4. Siting and Exposure ..................................................3
4.1 Wind Speed and Direction ...................................................................3
4.2 Temperature and Relative Humidity....................................................4
4.3 Precipitation .........................................................................................4
4.4 Solar Radiation.....................................................................................5
4.5 Soil Temperature..................................................................................5
4.6 Siting References .................................................................................5
5. Overview .....................................................................6
6. Specifications.............................................................7
7. UT20/UT30 Tower Installation ...................................8
7.1 Installing the UT20/UT30 ....................................................................8
7.1.1 Base and Guy Anchor Layout.......................................................8
7.1.2 Tower Base Installation ................................................................9
7.1.2.1 B18 Base installation........................................................10
7.1.2.2 RFM18 Base Installation..................................................11
7.1.3 Guy Anchor Installation..............................................................13
7.1.3.1 UTEYE Eyebolt Guy Anchor...........................................13
7.1.3.2 UTDUK Duckbill Guy Anchor ........................................13
7.1.4 Tower Assembly .........................................................................15
7.1.5 UTGND Tower Grounding Kit...................................................17
7.1.6 Attaching the Lightning Rod ......................................................18
7.2 Crossarms and Mounting Brackets ....................................................19
7.2.1 Crossarms ...................................................................................19
7.2.2 CMB200 Crossarm Brace Kit.....................................................20
7.2.2.1 Components......................................................................20
7.2.2.2 Assembly..........................................................................21

Table of Contents
ii
Figures
4-1. Effect of a structure on wind flow....................................................... 3
5-1. UT20 tower ......................................................................................... 6
7-1. UT20/30 weather tower....................................................................... 8
7-2. Guy anchor locations........................................................................... 9
7-3. Concrete base dimensions ................................................................. 10
7-4. Tower attached to the B18 legs ......................................................... 10
7-5. UT20/UT30 leg placement................................................................ 11
7-6. RFM18 base dimensions ................................................................... 12
7-7. RFM18 flat roof mounting base ........................................................ 13
7-8. UTEYE eyebolt guy anchor .............................................................. 13
7-9. UTDK duckbill guy anchor being driven into the ground................. 14
7-10. UTDUK duckbill in load-lock position............................................. 14
7-11. Guy wire attached to tower ............................................................... 15
7-12. UT20/30 lightning rod and mounting bracket ................................... 16
7-13. Guy wire/turnbuckle attached to the UTEYE anchor........................ 16
7-14. Ground rod and clamp....................................................................... 17
7-15. Tower grounding clamp .................................................................... 18
7-16. Lightning rod..................................................................................... 18
7-17. Crossarm mounting ........................................................................... 19
7-18. CMB200 Crossarm Brace Kit ........................................................... 20
7-19. CMB200 components........................................................................ 21
7-20. Bracket selection ............................................................................... 22
Tables
7-1. Crossarm lengths and materials......................................................... 19
7-2. Bracket Requirements ....................................................................... 22

1
UT20 and UT30 Universal Towers
1. Introduction
The 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 sturdy attachment points for antennas, solar
panels, environmental enclosures, radiation shields, and crossarms.
2. Precautions
2.1 Site Selection
•Select a safe site to install the tower.
•The distance between any power lines and the installation site should be at
least one and one-half times the height of the tower. Make the distance
even greater, if possible. Since all overhead lines look somewhat alike,
consider them all dangerous and stay well away from them.
•If there are power lines or buried utilities in the area, call the local utility
providers for assistance.
2.2 Tower Mounting
•NEVER work alone; always have someone near who can summon help.
•Certain clothing may provide a degree of safety, but do not depend on it
alone to preserve life (for example, rubber boots or shoes, industrial rubber
gloves, or a long shirt or jacket).
•Check local weather conditions. Be sure it has not rained recently, and the
ground is not wet or muddy. Make sure rain or thunderstorms are not
predicted for the day the tower is to be installed.
•To avoid having the tower being blown into nearby power lines, do not
install or remove towers in moderate or heavy winds.
•If it is necessary to use a ladder, choose a ladder made of non-conductive,
non-metallic materials.
•Have someone present who has been trained in electric shock first aid, if
possible.
2.3 Tower Installation
•Properly assemble the tower according to the instructions in this manual
(do this in the location the tower is to be installed).
•Once the tower is in its full vertical position, securely fasten the tower to
the base using 5/8-inch nuts and washers.
•Ground the tower in accordance with all applicable local electrical codes.

UT20 and UT30 Universal Towers
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3. Initial Inspection
3.1 Indoors
Immediately upon receipt of the tower:
•Inspect the shipping cartons for visible damage. Report any damage to
the shipping company.
•Open all shipping cartons.
•Check the contents of the cartons against the invoice. Contact
Campbell Scientific immediately if any parts are missing.
3.2 Outdoors
•Locate a suitable site for the tower (Section 4, Siting and Exposure (p. 3)).
•Prepare the tower base (Section 7, UT20/UT30 Tower Installation (p. 8)).
oInstall sensors to be mounted above a height of 3 m.
oRaise the tower (Section 7, UT20/UT30 Tower Installation (p. 8)).
oInstall the instrumentation enclosure (Section 7, UT20/UT30 Tower
Installation (p. 8)).
oInstall sensors to be mounted below a height of 3 m.
3.3 Tools Required
Tools required to install and maintain a Campbell Scientific tower:
•Shovel
•Rake
•Open end wrenches: 3/8 in, 7/16 in, 1/2 in, (2) 9/16 in
•Socket wrench set
•Magnetic compass
•Tape measure
•Nut driver (3/8 in)
•Level
•Sledgehammer
•Pliers
•Straight bit screwdrivers
•Phillips screwdrivers

UT20 and UT30 Universal Towers
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4. Siting and Exposure
If any part of the weather station comes into contact
with power lines, death or serious injury could occur.
Contact local utilities for the location of buried utility
lines before digging or driving ground rods.
Selecting an appropriate site for the weather station is critical to obtain accurate
meteorological data. In general, the site should be representative of the area
being studied, and away from the influence of obstructions such as buildings
and trees.
Do not place the weather station where sprinkler irrigation water will strike the
sensors or instrument enclosure.
The general guidelines for site selection given here were condensed from these
sources: EPA (2000)1, WMO (2010)2, and AASC (1985)3.
4.1 Wind Speed and Direction
As specified by the EPA1, wind sensors should be located over open, level
terrain at a distance at least ten times the height of any nearby buildings, trees,
or other obstructions as shown in FIGURE 4-1.
Standard measurement heights:
•3.0 m ± 0.1 m recommended (AASC)
•2.0 m ± 0.1 m, 10.0 m ± 0.5 m optional (AASC)
•10.0 m (WMO and EPA)
FIGURE 4-1. Effect of a structure on wind flow
DANGER

UT20 and UT30 Universal Towers
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4.2 Temperature and Relative Humidity
Sensors should be located over an open, level area at least 9 m (EPA1) in
diameter. The surface should be covered by short grass, or, where grass does
not grow, the natural earth surface. Locate sensors at a distance of at least four
times the height of any nearby obstructions and at least 30 m (EPA1) from
paved areas. Sensors must be protected from thermal radiation and adequately
ventilated.
Situations to avoid include:
•Industrial heat sources
•Rooftops
•Steep slopes
•Sheltered hollows
•Tall vegetation
•Shaded areas
•Swamps
•Areas where snow drifts occur
•Low places holding standing water after rainstorms
Standard measurement heights:
•1.5 m ± 1.0 m (AASC)
•1.25 to 2.00 m (WMO)
•2.0 m temperature (EPA)
•2.0 m and 10.0 m for temperature difference (EPA)
4.3 Precipitation
Rain gages must be sited on level ground covered with short grass or gravel. In
open areas, choose a site where the distance to any obstruction is two to four
times (EPA, AASC) the height of the obstruction.
Position the height of the opening as low as possible, but high enough to avoid
splashing from the ground. Wind shields, such as Campbell Scientific’s
260-953 Alter-Type Rain Gage Wind Screen, are recommended for open areas.
When necessary, use heated collectors to properly measure frozen
precipitation. The gage must be mounted above the average level of snow
accumulation in areas that experience significant snowfall.
Standard measurement heights:
•1.0 m ± 1.0 cm (AASC)
•30.0 cm minimum (WMO, EPA)

UT20 and UT30 Universal Towers
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4.4 Solar Radiation
Mount pyranometers in locations that avoid shadows on the sensor at any time.
Mounting the sensor on the southernmost (Northern Hemisphere) portion of the
weather station will minimize 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 m2and typical of the
surface of interest. The ground surface must be level to the immediate area
(10 m radius).
Standard measurement depths:
•10 cm ± 1.0 cm (AASC)
•5.0 cm, 10.0 cm, 50.0 cm, 100.0 cm (WMO)
4.6 Siting References
1EPA, (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
2WMO, (2008 edition, updated in 2010). Guide to Meteorological Instruments
and Methods of observation. World Meteorological Organization No 8, 2008
edition, Geneva Switzerland.
3The 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.

UT20 and UT30 Universal Towers
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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) 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.
FIGURE 5-1. UT20 tower

UT20 and UT30 Universal Towers
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6. Specifications
UT20 UT30
Measurement Height 6 m (20 ft) 10 m (30 ft)
Shipping Weight 23 kg (50 lb) 29 kg (65 lb)
Material Hardened drawn 6063-T832 Aluminum
Top 3 m Tube OD (outside diameter) 2.5 cm (1 in) 2.5 cm (1 in)
Top 3 m Width (center of tubing to center of tubing) 33.3 cm (13.1 in) 25.7 cm (10.1 in)
Center 3 m Tube OD n/a 2.5 cm (1 in)
Center 3 m Width (center of tubing to center of tubing) n/a 33.3 cm (13.1 in)
Bottom 3 m Tube OD 3.175 cm (1.25 in) 2.175 cm (1.25 in)
Bottom 3 m Width (center of tubing to center of tubing) 43.2 cm (17 in) 43.2 cm (17 in)
Vertical Pipe OD 2.5 cm (1 in)
Cross Support Pipe OD 0.953 cm (9.375 in)
Guyed Tower Area Requirements ~3.5 m (11.5 ft) radius ~5 m (17 ft) radius
Required Concrete Pad Dimensions for B18 Concrete
Mounting Base (Note 1) 91 L x 91 W x 122 D cm (36 x 36 x 48 in)
Maximum Wind Load Recommendations (Note 2) 110 mph (B18 base, unguyed.
110 mph (RBM18 base w/UTGUY)
Notes:
1. The concrete pad requirements assume heavy soil. Light, shifting, or sandy
soils require a bigger concrete pad.
2. The recommended wind load assumes proper installation, proper
anchoring, and total instrument projected area of less than two square feet.
For the RFM18 base, the wind load recommendation also assumes that the
UTGUY turnbuckles are preloaded to equalize tension, and the tower is
guyed at a 60-degree angle relative to the ground (maximum). The amount
of wind load that these towers can withstand is affected by quality of
anchoring and installation, guy wire tension, soil type, guy angle, and the
number, type, and location of instruments fastened to the tower.
3. The UT30 is Universal Towers model #9-30. A more detailed drawing of
this tower is available at www.universaltowers.com.

UT20 and UT30 Universal Towers
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7. UT20/UT30 Tower Installation
7.1 Installing the UT20/UT30
The UT20/UT30 tower provides a support structure for mounting the weather
station components. FIGURE 7-1 shows a typical UT20/UT30 equipped with
an instrumentation enclosure, meteorological sensors, and a solar panel.
FIGURE 7-1. UT20/30 weather tower
7.1.1 Base and Guy Anchor Layout
The UT20/UT30 tower attaches to a user-supplied concrete foundation as
shown in FIGURE 7-1. The base brackets, anchor bolts, and nuts are included
with the tower.
A guyed UT20 tower requires an area approximately 11.5 ft in radius, and a
guyed UT30 tower requires an area approximately 17 ft in radius. Brush and
tall weeds need to be removed. Otherwise, the natural vegetation and ground
surface should be disturbed as little as possible.
Drive a stake where the base of the tower will be located. Attach a line to the
stake and scribe a circle with an 11.5 ft radius for the UT20 or a 17 ft radius for
the UT30. The tower will be positioned so two legs will be parallel to the
equator as well as closest to the equator. The tower will then tilt away from the
equator at an angle for servicing as shown by the two tilt direction options in
FIGURE 7-2. Drive a stake on the scribed line opposite the direction the tower
will hinge for the first guy anchor location.

UT20 and UT30 Universal Towers
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When using a UT30 on level ground, lay out the remaining two anchor
locations by measuring 29.5 ft from the first anchor to the scribed line on either
side of the base stake (FIGURE 7-2). When using a UT20 on level ground, lay
out the two remaining anchor locations 20 ft from the first anchor to the scribed
line on either side of the base stake.
FIGURE 7-2. Guy anchor locations
On unlevel ground, use a compass at the base stake to lay out the remaining
two anchor locations 120 degrees from the first. Vary the distance between the
tower and each anchor so that the angle between the tower and the guy wire
will be approximately 30 degrees.
7.1.2 Tower Base Installation
There are two base options: the B18 base is poured in concrete; the RFM18
roof mount base is anchored to a flat surface.

UT20 and UT30 Universal Towers
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7.1.2.1 B18 Base installation
1. Dig a hole 36 inches square and 48 inches deep where the tower base will
be located. FIGURE 7-3 shows these dimensions.
FIGURE 7-3. Concrete base dimensions
2. Optional: construct a concrete form out of 2-inch x 4-inch lumber, 36
inches square (inside dimensions). Center the form over the hole and drive
two stakes along the outside edge of each side. Level the form by driving
nails through the stakes and into the form while holding the form level.
3. Attach the bottom section of the tower to the B18 base using one bolt per
leg (see FIGURE 7-4), making sure that the hinge direction is common for
all legs.
FIGURE 7-4. Tower attached to the B18 legs
Mounting
Bolts

UT20 and UT30 Universal Towers
11
4. Center the bottom tower section with the base attached in the hole. Orient
the tower so one side is aimed toward the equator, but the angle of the
hinges will allow the tower to tilt away from the equator at an angle.
FIGURE 7-5 shows both tilt options. Leg 1 will be one of the two legs
along the side aimed at the equator. This positioning allows a solar panel
to be attached to two tower legs while providing easy access to sensors at
the top of the tower.
5. Fill the hole with concrete. Getting the bottom tower section plumb is very
important. As concrete is poured into the hole, periodically check the
tower for plumb using a carpenter’s level and adjust as necessary. Make
sure there is 4 inches from the top of each B18 base to the top of the
concrete as shown in FIGURE 7-3. Allow three to four days for the
concrete to cure.
FIGURE 7-5. UT20/UT30 leg placement
7.1.2.2 RFM18 Base Installation
Position the RFM18 on the surface where it will be installed. Make sure the
hinge direction is correct and mark the locations of the four mounting holes.
Refer to FIGURE 7-5 for possible tilt directions. FIGURE 7-6 shows the
RFM18 dimensions and hole spacing. Install an anchor (user-supplied)
sufficient to support the tower for each hole.

UT20 and UT30 Universal Towers
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FIGURE 7-6. RFM18 base dimensions
Attach the bottom section of the tower to the RFM18 base by using one
9/16-inch bolt per leg (FIGURE 7-7). Position the base over the anchor holes.
Secure the base to the anchors by using appropriate hardware (user supplied).
Check the tower for plumb and shim the RFM18, if necessary, before fully
tightening the bolts.
When using the RFM18, the user-supplied mounting hardware
must be capable of withstanding the Maximum Wind Load given
in Section 6, Specifications (p. 7). See Note 2 in that section for a
description of factors that affect wind load. In addition, the tower
must make use of guy wires to further increase the stability of the
tower.
NOTE

UT20 and UT30 Universal Towers
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FIGURE 7-7. RFM18 flat roof mounting base
7.1.3 Guy Anchor Installation
There are two types of anchors for the tower guy wires: the UTEYE eye bolts
are poured in concrete; the UTDUK duckbill anchors are driven into the soil.
7.1.3.1 UTEYE Eyebolt Guy Anchor
1. Dig a hole 24 inches square by 24 inches deep at each anchor location
(Section 7.1.1, Base and Guy Anchor Layout (p. 8)).
2. Optional Construct a concrete form out of 2-inch x 4-inch lumber, 24
inches square (inside dimensions) for each hole. Center the forms over the
holes and level them by using a carpenter’s level and stakes.
3. Fill the holes with concrete and install the eyebolts as shown in FIGURE
7-8.
FIGURE 7-8. UTEYE eyebolt guy anchor
7.1.3.2 UTDUK Duckbill Guy Anchor
1. Locate the three anchor locations (Section 7.1.1, Base and Guy Anchor
Layout (p. 8)). It is important that the anchors be driven at the same angle as
RFM18
Mounting Hole
(4) places

UT20 and UT30 Universal Towers
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the guy wires (FIGURE 7-9). Insert the steel drive bar into the anchor
body and drive the anchor into the ground by using a fence post driver or
sledgehammer until only the top half of the loop remains above the
ground.
FIGURE 7-9. UTDK duckbill guy anchor being driven into the ground
2. Attach a high-lift jack to the loop and jack the anchor up about 6 inches to
rotate the anchor into the load-lock position (FIGURE 7-10).
Failure to install and lock the anchor at the correct angle
will result in the anchor cable cutting through the soil
until the angles equalize, causing slack in the guy wires.
FIGURE 7-10. UTDUK duckbill in load-lock position
WARNING