Specifications

16 WS-PRO LT weather station

AppendixA–GroundingRecommendations

A.1 Grounding System Installation

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Topreventlightningdamagetoyourequipment,RainBirdrecommendsinstallingagrounding

systemfortheequipment(includingcontrollers,weatherstations,andcentralcontrolsystems).

Thegroundingsystemdischargeslightning‐inducedelectricalcurrentintotheearthratherthan

allowthesurgetopassthroughpowerwiresorfieldwirestoyourequipment’selectronic

components.

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A.1.1 GroundResistance

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Groundresistanceoccurswhengroundingsystemcomponents,orthesoilitself,oppose

theflowofelectricityintotheearth.Groundresistanceismeasuredinunitscalled

“ohms”(Ω).Thehigherthegroundresistance(higherohmreadings),thelesschancethe

surgewillbeshuntedtogroundratherthantotheequipment’selectroniccomponents.

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FigureA.1‐1showspointswheregroundingsystemscandevelopresistance.Todecrease

groundresistance,RainBirdrecommendsirrigatingthesoilaroundthegrounding

system.Eachgroundingsystemshouldhaveadedicatedirrigationzonewithsprinkler

headsanditsownwateringprogramtomaintainsoilmoisturearoundthegrounding

system.

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Aproperlyinstalledgroundingsystemshouldmaintainamaximumgroundresistanceof

10ohms,orless.Ifyouareunabletoreacharesistanceof10ohmsorless,youcan

decreaseresistancebysurroundingthegroundingrodsorplateswithground

enhancementmaterial,suchasPOWERSETfromPaigeElectricCorporation(P/N

1820058),orGEMfromERICO(P/NGEM‐25A).

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Ifgroundresistancestillmeasureshigherthan10ohms,youcanextendthegroundrod

lengthasdescribedin“GroundRodStacking,”oruseadditionalgroundingrods,as

showningroundingsystemdesign“Y”(Alternate).

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A.1.2 InstallationRequirement

Thefollowingrequirementsapplytoallgroundingsystemdesigns(designYandthe

“GroundingPlate”design).Allgroundingrodsorplatesmustbeconnectedtogether

belowgradewith#6AWGorlargersolidbarecopperwire.

Installtheconnectingwireinasstraightalineaspossible.Ifyoumustmakeaturnor

bendinthewire,maketheturninasweepingcurvewithaminimumradiusofeight

inchesandaminimumincludedangleof90

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