ASTM_E_1596_-_99.pdf

Designation:E 1596 99Standard Test Methods forSolar Radiation Weathering of Photovoltaic Modules1This standard is issued under the fixed designation E 1596;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon(e)indicates an editorial change since the last revision or reapproval.1.Scope1.1 The three radiant energy weathering procedures de-scribed in these test methods are intended to determine theeffects of extended outdoor exposure-induced stress that mayoccur during service life of photovoltaic modules.1.1.1 Because most accelerated weathering devices are notlarge enough to accept full-sized photovoltaic modules,thesimulated weathering test procedures may be suitable only forsmaller test modules.The construction of smaller test modulesshould be as close in design and function as possible tofull-size modules.1.2 The three solar weathering test methods are as follows:1.2.1 Procedure ANatural sunlight,real-time exposuretesting,1.2.2 Procedure BAccelerated exposure testing concen-trated natural sunlight,and1.2.3 Procedure CAccelerated exposure testing usingsimulated sunlight.1.3 The test methods do not provide for weathering studieson individual components of photovoltaic modules.1.4 There is no similar or equivalent ISO Standard.1.5 UnitsThe values stated in SI units are to be regardedas the standard.No other units of measurement are included inthis standard.1.6 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:E 772 Terminology Relating to Solar Energy Conversion2E 1036 Test Methods for Testing the Electrical Performanceof Nonconcentrator Terrestrial Photovoltaic Modules andArrays Using Reference Cells2E 1328 Terminology Relating to Photovoltaic Solar EnergyConversion2E 1462 Test Methods for Insulation Integrity and GroundPath Continuity of Photovoltaic Modules2G 7 Practice for Atmospheric Environmental ExposureTesting of Nonmetallic Materials3G 26 Practice for Operating Light-Exposure Apparatus(Xenon-Arc Type)With and Without Water for Exposureof Nonmetallic Materials3G 90 Practice for Performing Accelerated Outdoor Weath-ering of Nonmetallic Materials Using Concentrated Natu-ral Sunlight33.Terminology3.1 DefinitionsDefinitions of terms used in this testmethod may be found in Terminologies E 772 and E 1328.3.2 Definitions of Terms Specific to This Standard:3.2.1 test specimen,na full-size photovoltaic module,or asmaller size photovoltaic module fabricated with similar ma-terials and processing as a full-size module,that will besubjected to the solar weathering tests.3.2.2 total UV dose,nsee UV below 385 nm.3.2.3 UV below 385 nm,nthe radiant exposure in W/m2ofwavelengths shorter than 385 nm incident upon a test speci-men.4.Summary of Test Methods4.1 Three solar weathering test methods are provided fordetermining the effects of extended outdoor exposure-inducedstress that may occur during service life of photovoltaicmodules.4.2 The duration of each of the test methods is determinedby the amount of time needed to accumulate a total ultraviolet(wavelengths shorter than 385 nm)exposure of 2000 MJ/m2,which is roughly equivalent to 72 months exposure in southernU.S.latitudes.If no failure mechanisms are detected ormeasured after 2000 MJ/m2of UV radiant exposure,testingshall continue until the photovoltaic module failure mecha-nisms are characterized or until the UV radiant dose exceeds6600 MJ/m2.4.3 The three test methods are:1These test methods are under the jurisdiction of ASTM Committee E-44 onSolar,Geothermal,and Other Alternative Energy Sources and is the directresponsibility of Subcommittee E44.09 on Photovoltaic Electric Power Systems.Current edition approved Oct.10,1999.Published November 1999.Originallypublished as E 1596-94.Last previous edition E 1596-94.2Annual Book of ASTM Standards,Vol 12.02.3Annual Book of ASTM Standards,Vol 14.04.1Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959,United States.4.3.1 Procedure AExposure in natural sunlight on a fixed-angle rack facing the equator or on a tracking rack.4.3.2 Procedure BExposure in a Fresnel reflector panelrack that provides concentrated natural sunlight irradiation byfollowing the sun and focusing the sunlight on the test modulesby means of mirrors.The test modules may be wettedperiodically by distilled or deionized water spray.4.3.3 Procedure C Exposure in an apparatus that provideshigh intensity simulated sunlight illumination of the photovol-taic modules from a filtered xenon arc light source.The testmodules may be wetted periodically by distilled or deionizedwater spray.