Eddy Flux Tower MountingConsiderations and Suppliers

Technical Note #132

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Mounting Hardware SuppliersThe following suppliers offer fittings and pipingoptions for mounting a LI-COR analyzer to a tripodor tower. Any metal pipe from your local hardwarestore can be used with these fittings, as long as theyhave been properly sized and finished; however, thesources below offer custom piping options for yourconvenience. For instrument mounting projectsLI-COR recommends aluminum fittings and pipes.The pipe sizes and additional fittings depend onyour sonic anemometer and setup configuration.The mounting hardware included with the LI-7200,LI-7500A, and LI-7700, however, is designed to beused with a 1 inch pipe.

Mounting your LI-COR analyzer to a tower (near thesonic anemometer):

● 0.75 in. diameter × 10 in. long aluminum pipe● 1.0 in. × 0.75* in. crossover fitting (2) - connects

directly to the mounting post● 1.0 in. × 0.75* in. crossover fitting● 0.75 in. diameter × 12 in. long aluminum pipe

*This assumes a 0.75 in. diameter pipe; howeveryou can use any size pipe you would like.

You will also need:● 4 ft. crossarm with bracket● Mounting brackets for LI-7550 Analyzer Interface

Unit - dimensions 13.8” × 11.8” × 5.9” (35cm ×30cm × 15cm)

NuRail(http://www.nurail.com ), of Metropolitan Pipe andSupply Company, offers everything needed tomount your LI-COR analyzer to an industrial tripodor tower. NuRail offers aluminum fittings in a widevariety of configurations and sizes ranging from 3/4in. to 2 in. NuRail also has a pipe fabricationservice for custom made integrated fittings andpipes.

NuRail Crossover fittings

Diamond Aluminum Company(http://www.diamond-aluminum.com) is a structuralaluminum fittings and pipe company that sells avariety of fitting configurations (made of high-strength, light-weight aluminum alloy) and piping(available in 4 different sizes, ordered by the footand custom cut to fit your needs). DownloadDiamond's product catalog to learn more aboutmaterial specifications and unique designs.

Diamond Aluminum Company Crossover fittings(http://www.diamond-aluminum.com/fittingpages/200.htm)

1.0 in. × 0.75 in.crossover fitting - p/n8783

1.0 in. × 0.75 in.crossover fitting - p/n 200 (PA)

Typical tripod mountingconfiguration (LI-7500Ashown). The mountingpost included with theLI-7200 and LI-7500A is3/4” Diameter.

For use with:• LI-7200 CO2/H2

O Analyzer• LI-7500A CO2/H2

O• LI-7700 CH4

Analyzer

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LI-7550LI-7550LI-7550

Tripod

LI-7550 AnalyzerInterface Unit

SonicAnemometer

LI-7500ASensor Head

Crossarm

Crossover Fittings

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1

Mounting Post (3/4”)

Crossover Fitting (1” x 3/4”)

Crossarm (1”)

2

Tower and Tripod SuppliersWhen setting up your LI-COR instrument, depending onwhat your research needs are, you will need a tripod or atower to support your equipment. LI-COR does not manu-facture these items; however, we do recommend purchasingsomething similar to the items shown below. Please keep inmind that the tripod/tower must be able to support theweight load of your equipment setup, must be a properheight, and must be able to withstand variable weatherconditions. Speak with a representative at the companieslisted below to help determine which setup will be right foryou.

Rickly Hydrological Company(http://www.rickly.com) manufactures and distributesinstrumentation equipment such as industrial strengthtripods and towers for outdoor use. Their durable andweatherproof designs are accurate and affordable, as well aslightweight for easy handling and quick assembly.

Model 3574 - 20 ft. portable tripod (p/n 1002-155)● Weight= 66 lbs. (30 kg)● Set-up time = 45 minutes● Adjustable base legs for uneven terrain

Model 3576 - 10 ft. portable tripod (p/n 1002-168)● Weight= 18 lbs. (8.2 kg)● Set-up time = 10 minutes● 6 ft., 15 lb. (6.8 kg) option also available● Each leg can be staked to the ground for added stability● Best for temporary or quick deployment applications

Model 3578 - 10 ft. Standpipe aluminum tower (p/n 1002-175)● Weight= 65 lbs. (29.5 kg)● 12 in. diameter pipe offers little wind resistance● Standpipe serves as protection to electrically sensitive

equipment● Best for long term applications

LUKSA Industries Inc.(http://www.luksa.com) designs and manufactures mechani-cally operated aluminum tripods. Tripods are rugged andportable for quick and easy deployments, free-standing withadjustable legs for uneven terrain, weatherproof, andprovide excellent stability. Tripods feature a crank-up, fullylocking extension system suited to fit your needed heightspecifications. Options include a 6 ft. tripod which can beextended to a height of 30 ft. (weight is 30 pounds) or a 7 ft.tripod which can be extended to a height of 40 ft. (weight is35 pounds).

HI-VIEW30 Tripod (http://www.luksa.com/hiview.html)HI-VIEW40 Tripod (http://www.luksa.com/hiview.html)

Rohn(http://www.rohnnet.com) provides towers to communica-tions companies; made of galvanized steel, these towersassure corrosion free use and have the ability to withstandharsh weather elements. The types and sizes of towers vary,from self supporting towers, to guyed towers, to bracketedtowers. Sizes range from 10' to 100'.

Self-Supporting Towers(http://www.rohnnet.com/rohn-g-series-self-supporting-tower )● 10 ft. tower (p/n 25SS010)● Sizes range up to 80 ft.● Download the Self Supporting G-Series Brochure for

more information

Guyed Towers(http://www.rohnnet.com/guyed-towers )● Best for larger towers

Bracketed Towers(http://www.rohnnet.com/bracketed )● Best for larger towers

Climatronics Corporation(http://www.climatronics.com) offers a variety of weathermonitoring instruments and towers. These aluminum towersfeature a triangular design, are lightweight and transport-able, wind resistant (up to 110 mph), and require minimalset-up time. Towers range in sizes from 10 ft. up to 80 ft.and weigh 13 lbs. up to 247 lbs. (5.9 - 112.3 kg).

Model # C-10: 10 ft. tower, 13 lbs. (5.9 kg)Model # C-20: 20 ft. tower, 26 lbs. (11.8 kg)Model # C-30: 30 ft. tower, 38 lbs. (17.3 kg)Larger model #'s can be found by downloading the Free-standing Aluminum Towers brochure:(http://www.climatronics.com/Products/Accessories/meteorological_towers.php )

● For mounting in areas of high wind conditions, the GuyKit (p/n 101004) provides further tower stability

GlenMartin(http://www.glenmartin.com) produces towers and accesso-ries in a variety of sizes from 30 feet to 70+ feet. Thesetowers feature strong diagonal construction to withstandhigh wind speeds and are durable and maintenance free.Added bonuses: A hinged base system allows for easyinstallation, a pulley system works as a functioning elevatorto raise and lower equipment with no need for towerclimbing, and Glen Martin also offers lightning rod towersolutions.

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M-13 Hazer Towers (SKU M-1330A)30' Hazer Tower Package● Preassembled● Weight= 370 lbs. (168 kg)40' Hazer Tower Package (SKU M-1340A)● Preassembled● Weight= 415 lbs. (188.6 kg)50' Hazer Tower Package (SKU M-1350A)● Preassembled● Weight= 450 pounds (204.5 kg)

Download the product catalog for more information aboutthese towers, accessories, and options at:(http://www.glenmartin.com/amateur.html).

Tower/Tripod Guying and Anchoring EquipmentFreestanding towers and tripods are exposed to a variety ofenvironmental conditions, one of which is the potential forhigh wind speeds. To ensure that your tower remainsupright, guying cables and anchors should be used. Thecompanies listed below offer anchoring solutions forsecuring flux towers.

Foresight Products, LLC(http://foresightproducts.com/duckmain.html) is a manufac-turer of earth anchors for all types of applications. Duckbillearth anchors require no digging, concrete, or holes, makingthem a reliable and time saving device for safely anchoringyour tripod to the study site. This company offers effective,lightweight, and economical anchoring solutions withexcellent holding capacities.

Multi-purpose: Model 88-DB1● 3,000 lb. (1364 kg) anchor holding power in normal soil● Cabled with 3.5 feet of 1/4 inch galvanized aircraft cable* You will need the DS-88 Drive Steel to install the anchor

GlenMartin(http://glenmartin.com/catalog/page17.html) is a towerinfrastructure solutions provider that sells commercial self-supporting and fold-over tower systems, amateur radiotowers, guying accessories and lightning protection. Inaddition, GlenMartin offers complete manufacturing,engineering, warehousing, transportation, and constructionservices.

Item # ES-40● 2,500 lb. (1136 kg) anchor holding power in normal soil● 30" anchor length* You will need to purchase guying cable separately* Item # WRS-250: 1/4 inch cable with 1280 lb. (582 kg)working load

Tripod/Tower Lightning ProtectionEddy covariance flux tower systems are typically exposed tovariable environmental conditions. Thus, it is very importantto have proper lightning protection. There are four mainparts to any grounding system: 1) lightning rod; 2) ground-ing plane; 3) grounding wire, and 4) the bond betweenthem. Further details, guidelines, and suggested lightningprotection providers are listed below.

The Grounding PlaneThe best grounding planes are:● Copper or copper- clad ground rods driven into the earth● Copper water pipes or building grounds with metal

structural frames● Metal enclosures and casings (which should be grounded

to earth ground)

Grounding rods should be either copper or galvanized steel● Minimum diameter of 5/8 in.

Note: Aluminum should not be used as a grounding rod, asthe alkalinity of the soil will etch the metal, causing discon-nection and in increase in impendence between the ground-ing system and earth ground.

The Grounding Wire● Use heavy wire gauges (10 AWG or larger) for running

the grounding wire● The cable can be solid or stranded, the wire can be either

bare or insulated

The Bond between them● The use of dissimilar metals between the surge protection

device and the grounding plane should be avoided● Ground clamps should be used to bond the grounding

wires to the grounding plane● Both copper and aluminum are approved for use in

grounding protection systems; however, copper is abetter conductor of electricity and can be used in smallergauges

Proper Installation Guidelines● Do NOT sharply bend the surge protection wires during

termination; offer a straight path to the ground● Keep the surge protection wires as short as possible to

improve effectiveness and response time● Keep the surge protection device a few feet away from

the equipment to allow proper response time for thetransient voltage to be suppressed

● Ensure all systems connect to the same grounding pointonly ONCE

Reference: http://www.ul.com/global/documents/corporate/aboutul/publications/newsletters/electricalconnections/july09.pdf

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4647 Superior Street • P.O. Box 4425 • Lincoln, Nebraska 68504 USANorth America: 800-447-3576 • International: 402-467-3576 • FAX: 402-467-2819 • envsales@licor.com • envsupport@licor.com • www.licor.comIn Germany and Norway – LI-COR Biosciences GmbH: +49 (0) 6172 17 17 771 • envsales-gmbh@licor.com • envsupport-gmbh@licor.comIn UK and Ireland – LI-COR Biosciences UK Ltd.: +44 (0) 1223 422102 • envsales-UK@licor.com • envsupport-UK@licor.com 75H-106, 7/10

Suggested Sources:1. Glen Martin Lightning Protection Package (http://www.glenmartin.com/catalog/lightning.htm)

● A complete kit which provides everything needed toprotect your tower and instrumentation againstdamaging lightning

● p/n LR-8400

2. Radio Shack (http://www.radioshack.com )

3. Thompson Lightning Protection (http://www.tlpinc.com/TLPProfile/products.htm )

● Best for commercial use

4. Local electronic supply company