BS EN 61 646:2008 Incorporating Corrigendum August 2009 BSI Standards Publication Thin-film terrestrial photovoltaic (PV) modules — Design qualification and type approval BS EN 61 646:2008 BRITISH STANDARD National foreword This British Standard is the UK implementation of EN 61 646:2008 It is identical to IEC 61 646:2008 It supersedes BS EN 61 646:1 997 which is withdrawn The UK participation in its preparation was entrusted to Technical Committee GEL/82, Solar photovoltaic energy systems A list of organizations represented on this committee can be obtained on request to its secretary This publication does not purport to include all the necessary provisions of a contract Users are responsible for its correct application © BSI 2009 ISBN 978 580 68994 ICS 27.1 60 Compliance with a British Standard cannot confer immunity from legal obligations This British Standard was published under the authority of the Standards Policy and Strategy Committee on 31 July 2009 Amendments issued since publication Date Text affected 31 August 2009 Correction to missing CENELEC pages EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM EN 61 646 August 2008 ICS 27.1 60 Supersedes EN 61 646:1 997 English version Thin-film terrestrial photovoltaic (PV) modules Design qualification and type approval (IEC 61 646:2008) Modules photovoltaïques (PV) en couches minces pour application terrestre Qualification de la conception et homologation (CEI 61 646:2008) Terrestrische Dünnschicht-Photovoltaik (PV)-Module Bauarteignung und Bauartzulassung (IEC 61 646:2008) This European Standard was approved by CENELEC on 2008-06-01 CENELEC members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Central Secretariat or to any CENELEC member This European Standard exists in three official versions (English, French, German) A version in any other language made by translation under the responsibility of a CENELEC member into its own language and notified to the Central Secretariat has the same status as the official versions CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Cyprus, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom CENELEC European Committee for Electrotechnical Standardization Comité Européen de Normalisation Electrotechnique Europäisches Komitee für Elektrotechnische Normung Central Secretariat: rue de Stassart 35, B - 050 Brussels © 2008 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members Ref No EN 61 646:2008 E BS EN 61 645:2008 EN 61 646:2008 -2- Foreword The text of document 82/51 2/FDIS, future edition of IEC 61 646, prepared by IEC TC 82, Solar photovoltaic energy systems, was submitted to the IEC-CENELEC parallel vote and was approved by CENELEC as EN 61 646 on 2008-06-01 This European Standard supersedes EN 61 646:1 997 EN 61 646:2008 includes the following significant technical changes with respect to EN 61 646:1 997: The major change is in the pass/fail criteria It no longer relies on meeting a plus/minus criterion before and after each test, but rather on meeting the rated power after all of the tests have been completed and the modules have been light-soaked This was done to eliminate the technology-specific preconditioning necessary to accurately measure the changes caused by the test (Some modules lose power in light while others lose power during dark heat.) Since all modules must work after exposure to light, this seemed like a good approach and will streamline the test procedure, hopefully reducing the testing cost – updated normative references; – added a definition of “minimum value of maximum output power”; – modified the wording in major visual defects to allow some bending and misalignment without failure; – added requirements to the report from EN ISO/IEC 7025; – removed the “Twist Test” as was done from EN 61 21 5, since no one has ever failed this test; – made the pass/fail criteria for insulation resistance and wet leakage current dependent on the module area; – added the temperature coefficient of power ( δ) to the required measurements; – modified temperature coefficient section to allow for measurements under natural sunlight or a solar simulator; – deleted reference plate method from NOCT; – added apparatus sections to those test procedures that did not have apparatus sections in EN 61 646:1 997; – rewrote the hot-spot test; – eliminated edge dip method from wet leakage current test; – changed mechanical load test to cycles to be consistent with other standards; – added bypass diode thermal test The following dates were fixed: – latest date by which the EN has to be implemented at national level by publication of an identical national standard or by endorsement (dop) 2009-03-01 – latest date by which the national standards conflicting with the EN have to be withdrawn (dow) 201 -06-01 Annex ZA has been added by CENELEC -3- BS EN 61 646:2008 EN 61 646:2008 Endorsement notice The text of the International Standard IEC 61 646:2008 was approved by CENELEC as a European Standard without any modification In the official version, for Bibliography, the following notes have to be added for the standards indicated: IEC 60904-5 NOTE Harmonized as EN 60904-5:1 995 (not modified) IEC 60904-8 NOTE Harmonized as EN 60904-8:1 998 (not modified) BS EN 61 645:2008 EN 61 646:2008 -4- Annex ZA (normative) Normative references to international publications with their corresponding European publications The following referenced documents are indispensable for the application of this document For dated references, only the edition cited applies For undated references, the latest edition of the referenced document (including any amendments) applies NOTE When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD applies Publication IEC 60068-1 Year -1 ) IEC 60068-2-21 -1 ) IEC 60068-2-78 2001 IEC 6041 -1 ) IEC 60721 -2-1 -1 ) IEC 60891 -1 ) IEC 60904-1 2006 IEC 60904-2 -1 ) IEC 60904-3 -1 ) IEC 60904-7 -1 ) IEC 60904-9 -1 ) IEC 60904-1 -1 ) IEC 61 21 -1 ) 1) 2) Undated reference Valid edition at date of issue Title EN/HD Environmental testing EN 60068-1 Part : General and guidance Environmental testing EN 60068-2-21 Part 2-21 : Tests - Test U: Robustness of terminations and integral mounting devices Environmental testing EN 60068-2-78 Part 2-78: Tests - Test Cab: Damp heat, steady state Sampling plans and procedures for inspection by attributes Classification of environmental conditions - HD 478.2.1 S1 Part 2-1 : Environmental conditions appearing in nature - Temperature and humidity Procedures for temperature and irradiance EN 60891 corrections to measured I-V characteristics of crystalline silicon photovoltaic devices Photovoltaic devices EN 60904-1 Part : Measurement of photovoltaic currentvoltage characteristics Photovoltaic devices EN 60904-2 Part 2: Requirements for reference solar devices EN 60904-3 Photovoltaic devices Part 3: Measurement principles for terrestrial photovoltaic (PV) solar devices with reference spectral irradiance data Photovoltaic devices EN 60904-7 Part 7: Computation of spectral mismatch error introduced in the testing of a photovoltaic device Photovoltaic devices EN 60904-9 Part 9: Solar simulator performance requirements Photovoltaic devices EN 60904-1 Part 0: Methods of linearity measurement Crystalline silicon terrestrial photovoltaic (PV) EN 61 21 modules - Design qualification and type approval Year 994 2) 2006 2) 2001 2) 989 2) 994 2) 2006 2) 2007 2) 2008 2) 998 2) 2007 2) 998 2) 2005 2) -5Publication ISO/IEC 7025 Year -1 ) BS EN 61 646:2008 EN 61 646:2008 Title EN/HD Year General requirements for the competence of EN ISO/IEC 7025 2005 2) testing and calibration laboratories BS EN 61 646:2008 –2– 61 646 I EC: 2008 CONTENTS FOREWORD Scope an d obj ect N orm ati ve references Sam plin g 8 10 M arkin g Testin g Pass criteri a M aj or visu al defects Report M od ifications 1 Test procedures 1 Visu al inspection 1 Purpose 1 Proced ure 1 Req uirem en ts M axim um power determ ination Purpose 2 Apparatus Proced ure I nsu lation test Purpose Apparatus 3 Test d iti on s Proced ure 5 Test req u irem ents M easurem ent of tem perature coeffici ents Purpose Apparatus Proced ure Measurem ent of n om in al operati n g cell tem perature (N OCT) Purpose I n trod ucti on Princi pl e Apparatus 5 Test m od u le m ou nting Proced ure Perform ance at STC an d N OCT 21 Purpose 21 Apparatus 22 Proced ure 22 Perform ance at low irrad i ance 22 Purpose 22 Apparatus 22 Proced ure 22 Outd oor exposure test 23 BS EN 61 646:2008 61 646 I EC: 2008 –3– Purpose 23 Apparatus 23 Proced ure 23 Fi nal m easurem en ts 23 Req uirem en ts 23 H ot-spot en d urance test 23 Purpose 23 H ot-spot effect 23 Cl assificati on of cel l i n tercon n ecti on 24 Apparatus 25 Proced ure 25 Fi nal m easurem en ts 26 Req uirem en ts 26 1 U V precond i tion i ng test 27 1 Purpose 27 1 Apparatus 27 1 Proced ure 27 1 Fi nal m easurem en ts 27 1 Req uirem en ts 27 1 Therm al cycl i n g test 27 1 Purpose 27 1 Apparatus 28 1 Proced ure 28 1 Fi nal m easurem en ts 28 1 Req uirem en ts 29 1 H um id ity-freeze test 29 1 Purpose 29 1 2 Apparatus 29 1 Proced ure 30 1 Fi nal m easurem en ts 30 1 Req uirem en ts 30 1 Dam p heat test 30 1 Purpose 30 1 Proced ure 30 1 3 Fi nal m easurem en ts 30 1 Req uirem en ts 30 1 Robustness of term in ati ons test 31 1 Purpose 31 1 Types of term in ati ons 31 1 Proced ure 31 1 4 Fi nal m easurem en ts 32 1 Req uirem en ts 32 1 Wet leakag e current test 32 1 Purpose 32 1 Apparatus 32 1 Proced ure 32 1 Req uirem en ts 32 1 Mech an ical l oad test 33 1 Purpose 33 BS EN 61 646:2008 –4– 61 646 I EC: 2008 1 Apparatus 33 1 Proced ure 33 1 Fi nal m easurem en ts 33 1 Req uirem en ts 33 1 H ail test 33 1 Purpose 33 1 Apparatus 33 1 Proced ure 35 1 Fi nal m easurem en ts 36 1 Req uirem en ts 36 1 Bypass d iode th erm al test 36 1 Purpose 36 1 Apparatus 37 1 Proced ure 37 1 Proced ure 38 1 Fi nal Measurem en ts 38 1 Req uirem en ts 39 1 Light-soakin g 39 1 Purpose 39 1 Apparatus 39 1 Proced ure 39 1 Fi nal m easurem en ts 39 1 Req uirem en ts 39 Bibli ograph y 40 Fi gu re – Qu al ification test seq uence Figu re – N OCT correction factor 21 Figu re – H ot-spot effect i n a th i n-fi lm m odu le wi th serial l y nected cells Worst case shad in g d iti on is sh adi n g of cells at the sam e tim e 24 Figu re – Th erm al cycl in g test 28 Figu re – H um i di ty-freeze cycl e 29 Figu re – H l test eq ui pm ent 35 Figu re – I m pact l ocati ons 36 Figu re – Bypass Di ode Therm al Test 38 Tabl e – Summ ary of test l evels Tabl e – I ce bal l m asses an d test velocities 34 Tabl e – I m pact locati on s 36 BS EN 61 646:2008 – 28 – 61 646 I EC: 2008 0.1 Apparatu s a) A cl im atic ch am ber with au tom atic tem perature trol, m eans for circu lating th e air insid e an d m eans to avoid d ensation on th e m odu le d urin g th e test, capabl e of subj ecting one or m ore m od u les to the therm al cycl e in Figure b) Means for m ou nting or supportin g the m od u l e(s) in the cham ber, so as to all ow free circulation of th e surrou n d in g air Th e th erm al duction of the m ou n t or support sh all be l ow, so th at, for practical purposes, the m od ul e(s) are th erm al l y isol ated c) Means for m easurin g an d record in g th e tem perature of the m od u le(s) to an accuracy of ±1 °C Temperature of module (°C) d) Means for m onitoring, through out the test, the tinu ity of the intern al circuit of each m odu le Maximum cycle time 00 °C/h max Minimum dwell time +85 Continue for specified number of cycles +25 Minimum dwell time –40 Time (h) IEC 590/08 Figu re – Thermal cycl ing test 0.1 Procedu re a) I nstall the m od u le(s) at room tem perature in th e cham ber b) Con nect th e tem peratu re m onitoring eq u ipm ent to th e tem perature sensor(s) Th e tem perature sensors sh al l be attached to the fron t or back surface of th e m od u l e, n ear the m idd le I f m ore than on e m od ul e is tested sim ultaneousl y, it wil l suffice to m on itor the tem perature of one represen tative sam pl e c) Cl ose th e ch am ber and , subj ect th e m od u le(s) to cycl in g between m od u l e tem peratures of –40 ° C ± °C an d +85 °C ± ° C, in accord ance with the profile in Figure The rate of chan ge of tem perature between th e l ow an d h igh extrem es sh all n ot exceed 00 °C/h an d th e m odu l e tem peratu re shall rem ain stabl e at each extrem e for a period of at l east m in The cycl e tim e shal l n ot exceed h The num ber of cycles sh all be as shown in th e rel evant blocks in Figure d) Throu ghou t the test, record the m odu l e tem perature and m on itor th e tin u ity of th e m odu les 1 Final measu rements After a m inim um recovery tim e of h , repeat test 1 an d BS EN 61 646:2008 61 646 I EC: 2008 – 29 – 0.1 Requirements – – – N o evid ence of m aj or visual d efects, as defin ed in Cl ause I nsu lation resistance sh al l m eet the sam e req uirem ents as for th e in itial m easurem ents N o open circuits d urin g the course of th e test 0.1 Humidity-freeze test 0.1 2.1 Purpose To determ ine th e abil ity of th e m odu l e to withstand th e effects of high tem perature an d hum idity fol l owed by su b-zero tem peratures Th is is n ot a th erm al sh ock test 0.1 2.2 Apparatus a) A clim atic ch am ber with au tom atic tem perature and hum idity control, capable of su bj ectin g on e or m ore m odu l es to the hum idity-freeze cycl e specified in Figure b) M ean s for m ou n tin g or su pportin g th e m od u l e(s) i n th e ch am ber, so as to al l ow free circu l ati on of th e su rrou n d in g air Th e th erm al d u ction of th e m ou n t or su pport sh al l be l ow, so th at, for practi cal pu rposes, th e m od u l e(s) are th erm al l y isol ated c) M ean s for m easu rin g an d record in g th e m od u l e tem peratu re to an accu racy of ±1 ° C (I t i s su fficien t to m on itor th e tem peratu re of one represen tati ve sam pl e, if m ore th an on e m od u l e is bei n g tested ) d) Means for m onitoring, through out the test, the tinu ity of the intern al circuit of each m odu le Continue for total of cycles 85 % ± % RH No RH control Module temperature (°C) +85 00 °C/h max Room temperature Start of cycle End of cycle 200 °C/h max –40 0,5 h 20 h h max Time (h) IEC 591/08 Figure – Humidity-freeze cycle BS EN 61 646:2008 – 30 – 61 646 I EC: 2008 1 2.3 Procedu re a) Attach a su itable tem perature sensor to th e front or back surface of th e mod u l e(s) n ear the m idd le b) I nstal l the m od u le(s) at room tem perature in th e cl im atic cham ber c) Connect the tem perature m onitorin g equ ipm en t to the tem perature sensor(s) d) After cl osin g th e ch am ber, su bj ect the m od u le(s) to com pl ete cycles in accord ance with Figu re Th e m axim um an d m inim um tem peratures shal l be with in ±2 ° C of the specified l evels and th e relative h um id ity sh al l be m aintain ed with in ±5 % of the specified val ue at th e m axim um tem perature (85 °C) e) Throu ghou t the test, record the m odu l e tem perature and m on itor th e tin u ity of th e m odu le(s) 1 2.4 Fin al measu rem ents Repeat tests 1 , an d with in two to four h ou rs after the com pletion of the test 1 2.5 Req ui rem ents – N o evid ence of m aj or visual d efects, as defin ed in Cl ause – I nsu lation resistance sh al l m eet the sam e req uirem ents as for th e in itial m easurem ents – N o open circuits d urin g the course of th e test 1 Damp heat test 1 3.1 Pu rpose To determ in e th e abil ity of the m odu l e to withstan d th e effects of lon g-term penetration of hum idity 1 3.2 Procedu re The test sh al l be carried ou t in accord ance with I EC 60068-2-78 with th e foll owing provisions: a) Precond ition ing The m odu le(s), being at room tem perature, sh al l be in trod uced into th e cham ber withou t precon dition ing b) Severities The foll owing severities are appl ied : Test tem perature: 85 °C ± °C Rel ative h um id ity: 85 % ± % Test duration: 000 h 1 3.3 Fin al measu rem ents After a recovery tim e of between h an d h, repeat tests an d 1 Repeat test 1 1 3.4 Req ui rem ents – – – N o evid ence of m aj or visual d efects, as defin ed in Cl ause I nsu lation resistance sh al l m eet the sam e req uirem ents as for th e in itial m easurem ents Wet leakage current test shal l m eet the sam e req u irem ents as th e in itial m easurem en ts BS EN 61 646:2008 61 646 I EC: 2008 – 31 – 1 Robu stn ess of termination s test 1 4.1 Pu rpose To determ in e th at the term inations and th e attach m ent of th e term in ations to th e bod y of th e m odu le wil l withstand su ch stresses as are l ikel y to be applied d urin g norm al assem bl y or han d ling operations 1 4.2 Types of termi nation s Three types of m od u le term inations are consid ered: type A: wire or fl yin g l ead ; type B: tags, thread ed studs, screws, etc ; type C: n ector 0.1 4.3 Procedu re Precon d ition ing: h at stan d ard atm osph eric d itions for m easurem en t and test 1 4.3 Type A terminations Tensil e test: as d escribed in I EC 60068-2-21 , test U a, with th e fol l owing provisions: – – all term in ations sh al l be tested; tensile force sh al l n ever exceed the m odu l e weight Ben d in g test: as d escribed in I EC 60068-2-21 , test U b, with th e fol l owing provisi ons: – – all term in ations sh al l be tested; m ethod -1 cycl es (one cycl e is one ben d in each opposite d irection) 1 4.3 Type B termin ati ons Tensil e an d ben d in g tests: a) for m odu l es with exposed term in als, each term ination sh all be tested as for type A term inations; b) if th e term in ations are encl osed in a protective box, th e followin g proced ure sh al l be appl ied : A cabl e of the size and type recomm end ed by th e m odu le m an ufacturer, cut to a su itabl e l en gth , shal l be conn ected to the term in ations insid e the box using th e m anufacturer's recom m end ed proced ures The cable shal l be taken throu gh the h ol e of the cable gl an d, taking care to util ize an y cable clam p arrangem ent provided The lid of the box sh al l be securel y replaced The m od u l e shal l then be tested as for type A term in ations Torqu e test: as d escribed in I EC 60068-2-21 , test U d, with th e fol l owing provisions: – – all term in ations sh al l be tested; severity The n uts or screws sh ou l d be capabl e of being loosen ed afterwards, u n less they are specifical l y d esign ed for perm anent attachm en t 1 4.3 Type C termin ati ons A cabl e of th e size an d type recomm en ded by th e m od u l e m an ufacturer, cut to a suitabl e l en gth , shal l be n ected to th e outpu t end of th e conn ector, and the tests for type A term inations shall be carried out BS EN 61 646:2008 – 32 – 61 646 I EC: 2008 1 4.4 Fin al measu rem ents Repeat tests 1 and 1 4.5 Req ui rem ents – N o evid ence of m aj or visual d efects, as defin ed in Cl ause – I nsu lation resistance sh al l m eet the sam e req uirem ents as for th e in itial m easurem ents 1 Wet leakage cu rrent test 1 5.1 Pu rpose To eval u ate the insu l ation of th e m od ul e u nd er wet operatin g d itions and verify th at m oistu re from rain , fog, dew or m elted sn ow does not enter th e active parts of th e m od u le circuitry, wh ere it m ight cause corrosion, a groun d faul t or a safety h azard 1 5.2 Apparatu s a) A sh all ow trou gh or tank of sufficient size to enable the m odul e with fram e to be pl aced i n th e solu tion i n a fl at, h orizon tal position I t shal l contain a water/wettin g agent sol ution sufficient to wet th e surfaces of the m odu l e u nd er test and m eeting the fol lowin g req uirem ents: Resistivity: 500 Ω ⋅ cm or l ess Tem perature: 22 °C ± °C The d epth of th e solu tion shal l be sufficien t to cover al l surfaces except j u nction box en tries not d esign ed for imm ersion b) Spray eq u ipm ent containing th e sam e sol ution c) DC voltage source, with curren t l im itation , capable of appl ying 500 V or th e m axim um rated system vol tage of the m od u le, wh ich ever is m ore d) I nstrum ent to m easure in su lation resistance 1 5.3 Procedu re N OTE Al l conn ecti ons sh al l be representati ve of th e recom m end ed fi el d wi ri n g i nstal l ati on an d precauti ons sh al l be taken to en su re th at l eakag e currents d o n ot ori gi n ate from th e i nstru m entati on wi ri n g attach ed to th e m odu l e a) I mm erse th e m od ul e in the tank of th e requ ired solu tion to a d epth sufficien t to cover al l surfaces except ju nction box en tries n ot d esign ed for im m ersion Th e cable en tries sh al l be thorough l y sprayed with solu tion I f th e m od ul e is provid ed with a m atin g n ector, the conn ector sh oul d be im mersed d uring th e test b) Con nect th e sh orted ou tpu t term inals of th e m odu l e to th e positive term inal of the test eq u ipm ent Con nect th e l iq u id test solu tion to th e n egative term in al of the test equ ipm en t usin g a su itable m etal l ic d uctor c) I ncrease th e vol tage appl ied by th e test eq u ipm ent at a rate n ot to exceed 500 V ⋅ s –1 to 500 V or th e m axim um system voltage for the m odu le (see m arking Clause 4), wh ich ever is greater M aintain th e voltage at th is level for m in Th en determ in e th e insul ation resistance d) Red uce the appl ied vol tage to zero and sh ort-circu it th e term inals of the test eq uipm en t to d ischarge th e voltage bu il d-u p on th e m odu le N OTE Ensu re that al l of th e wetti n g ag en t has been ri nsed off the m od ul es before conti n u i ng ad di ti onal tests 1 Req ui rem ents – For m od ules with an area less th an 0, m , th e in su lation resistance shal l not be less th an 400 M Ω ; BS EN 61 646:2008 61 646 – I EC: 2008 – 33 – for m odul es with an area larger th an 0, m , th e m easured insu l ation resistance tim es the area of the m odu l e sh al l not be l ess th an 40 M Ω⋅ m 0.1 Mechanical load test 0.1 6.1 Purpose To d eterm in e the abil ity of th e m od u l e to withstan d wind , sn ow, static or ice l oads 0.1 6.2 Apparatus a) A rigid test base wh ich en ables the m od u l es to be m oun ted fron t-sid e up or fron t-sid e down The test base sh al l enabl e th e m odu l e to deflect freel y d urin g the load appl icati on b) I nstrum entation to m on itor th e el ectrical continu ity of th e m odu l e d urin g th e test c) Suitabl e weigh ts or pressure m eans th at enabl e the load to be appl ied in a gradu al, un iform m an ner 0.1 6.3 Procedure a) Equ ip th e m odu l e so th at the electrical tinu ity of th e internal circu it can be m onitored tin u ousl y d uring th e test b) Mou nt th e m od u le on a rigid structure usin g th e m ethod prescribed by th e m anufacturer (I f th ere are d ifferen t possi bil iti es, use th e worst on e, wh ere th e d istance between th e fixin g points is at m axim u m ) c) On th e fron t su rface, appl y grad ual l y a l oad correspon d in g to 400 Pa, spread u n iform l y Mai ntain th is load for h d) Withou t rem ovin g th e m od u l e from the rigid stru cture, appl y th e sam e l oad on th e back surface of th e m od u le e) Repeat steps c) and d) for a total of three cycl es N OTE 400 Pa correspon d to a wi nd pressure of 30 km ⋅ h –1 (approxi m atel y ±800 Pa) wi th a safety factor of for g u sty wi nd s I f the m odu l e i s to be qu al i fi ed to wi thstan d h eavy accu m ul ati ons of sn ow and i ce, th e l oad appl i ed to the front of the m od u l e d uri n g thi s test i s i ncreased from 400 Pa to 400 Pa N OTE Test conditions higher than 400 Pa might become necessary if the module is to be qualified for general use in areas with snow or wind loads exceeding 400 Pa For example, snow load requirements can be concluded from relevant national standards or snow load maps N OTE I f d i fferent m oun ti n g m eth od s for th e m odu l e are perm i tted , th e test i s to be perform ed with d i fferent test fi gu rati on s represen ti ng th e ran ge of en vi sag ed m oun ti n g m ethod s 0.1 6.4 Final measurements Repeat tests 1 and 0.1 6.5 Requirements – – N o evid ence of m aj or visual d efects, as defin ed in Cl ause I nsu lation resistance sh al l m eet the sam e req uirem ents as for th e in itial m easurem ents 0.1 Hail test 0.1 7.1 Purpose To verify th at th e m od u l e is capabl e of withstand i n g th e im pact of hailston es 0.1 7.2 Apparatus a) Mou l ds of su itabl e m aterial for casting spherical ice bal ls of th e requ ired d iam eter Th e stan dard diam eter sh al l be 25 mm , bu t an y of th e oth er d iam eters l isted in Table m ay be specified for special en vironm ents BS EN 61 646:2008 – 34 – 61 646 I EC: 2008 b) A freezer, trolled at –1 °C ± °C c) A storage contain er for storin g the ice bal ls at a tem perature of –4 ° C ± ° C d) A l au ncher capabl e of propel l in g an ice bal l at the specified vel ocity, with in ±5 %, so as to h it th e m odu le with in th e specified im pact l ocation The path of th e ice ball from th e l au ncher to th e m odu l e m ay be h orizon tal , vertical or at an y interm ed iate an gle, so l ong as th e test req uirem en ts are m et e) Rigid m ou nt for supportin g th e test m od ule by th e m ethod prescribed by th e m an ufacturer, with th e im pact surface n orm al to th e path of th e proj ected ice bal l f) A balance for determ in in g th e m ass of an ice bal l to an accuracy of ±2 % g) An instrum ent for m easurin g th e vel ocity of th e ice bal l to an accuracy of ±2 % Th e velocity sensor sh al l be no m ore th an m from the surface of th e test m od ul e As an exam ple, Figure sh ows in schem atic form a suitabl e apparatus com prisin g a horizon tal pneum atic l aunch er, a vertical m od u le m oun t and a velocity m eter wh ich electron icall y m easures the tim e it takes the ice ball to traverse th e d istance between two l igh t beam s Table – Ice ball masses and test vel ociti es Di ameter M ass Test veloci ty Di am eter M ass Test veloci ty mm g m ⋅ s –1 mm g m ⋅ s –1 2, 0, 94 6, 45 43, 30, 15 , 63 7, 55 80, 33, 25 7, 53 23, 65 32, 36, 35 20, 27, 75 203, 39, BS EN 61 646:2008 61 646 I EC: 2008 – 35 – Regulator Test gauge Air supply m max Solenoid valve-large, fast-opening Photoelectric velocity measuring system Reservoir Interchangeable barrels Module Mounting frame IEC 591/08 Figure – Hail test equipment 0.1 7.3 Procedure a) U sin g th e m oul ds an d th e freezer, m ake enou gh ice bal ls of th e req uired size for the test, i ncl u d in g som e for th e prelim i nary adj ustm en t of the lau nch er b) Exam in e each on e for cracks, size an d m ass An acceptable bal l sh al l m eet th e fol l owing req uirem ents: – no cracks visibl e to the naked eye; – d iam eter with in ±5 % of that requ ired; – m ass with in ±5 % of th e appropriate n om inal val u e in Table c) Place the bal ls in the storage container an d leave them there for at l east h before use d) Ensure th at al l surfaces of th e l au nch er l ikel y to be in contact with th e ice balls are near room tem perature e) Fire a n um ber of trial sh ots at a sim ul ated target in accordance with step g) bel ow and adj ust the l aunch er un til th e velocity of th e ice bal l, as m easured with th e velocity sensor in th e prescribed position , is with in ±5 % of th e appropriate h ailston e test vel ocity in Table f) I nstal l th e m od u le at room tem perature in the prescribed m ou nt, with th e im pact surface norm al to th e path of th e ice bal l g) Take an ice bal l from the storage contain er an d place it in th e l au nch er Take aim at th e first im pact l ocation specified in Tabl e an d fire The tim e between th e rem oval of th e ice bal l from th e container and im pact on th e m od ule shal l n ot exceed 60 s BS EN 61 646:2008 – 36 – 61 646 I EC: 2008 h) I nspect th e m odu l e in th e im pact area for signs of dam age and m ake a n ote of an y visual effects of th e sh ot Errors of u p to m m from the specified l ocation are acceptabl e i) I f th e m od u le is u ndam aged, repeat steps g) and h) for al l the oth er im pact locations shown in Table 3, as il l ustrated in Figure Table – Impact locations Sh ot N umber Location A corn er of the m od ul e wi nd ow, n ot m ore than 50 m m from the fram e An edg e of the m od ul e, not m ore th an m m from th e fram e 3, Over th e edg e of th e ci rcu i t 5, Over th e ci rcui t near cel l i n tercon n ects 7, N ear th e poi nt of m ou nti ng on the ci rcui t 9, I n th e center of th e ci rcui t, farth est from the m ou nti ng poi n ts 11 An y poi nt whi ch m ay prove especi all y vu l n erabl e to hai l i m pact Mounting point 10 Mounting point IEC 592/08 Figu re – Impact locations 0.1 7.4 Final measu rements Repeat tests 1 and 1 7.5 Requi rements – – N o evid ence of m aj or visual d efects, as defin ed in Cl ause I nsu lation resistance sh al l m eet the sam e req uirem ents as for th e in itial m easurem ents 1 Bypass diode thermal test 1 8.1 Pu rpose To assess the ad eq uacy of the th erm al d esign and relative lon g-term rel iabil ity of th e bypass d iod es used to l im it the d etrim en tal effects of m od u le h ot-spot susceptibil ity I f th e bypass d iod es are not accessibl e in th e m od u l e type u nd er test, a special sam ple can be prepared for th is test Th is sam pl e sh all be fabricated to provid e th e sam e therm al en vironm ent for the d iod e as a stand ard prod uction m od u les un d er test and does n ot have to BS EN 61 646:2008 61 646 I EC: 2008 – 37 – be an active PV m od u l e, but m ust h ave access to m easure th e tem perature of the diode(s) durin g th e test Th e test shal l then proceed as n orm al Th is special test sam ple sh al l be used on l y for the bypass d iod e therm al test and not for the other tests in th e seq u ence 0.1 8.2 Apparatus a) Means for heatin g th e mod u le to a tem perature of 75 ° C ± ° C b) Means for m easurin g an d record in g th e tem perature of the m od u le(s) to an accuracy of ±1 °C c) Means for m easurin g the tem perature of an y bypass diodes provid ed with the m od u le Measurem ent of th e d iod e tem perature can be m ad e directl y usin g a temperature sensor or by m easurin g th e tem perature coefficient of vol tage drop across th e d iod es Care shou l d be taken to m inim ize an y alteration of the properties of th e diode or its heat transfer path d) Means for m easurin g the ju nction voltage of th e bypass diodes to an accuracy of 0, % e) M ean s for appl yi n g a cu rren t eq u al to , 25 tim es th e STC sh ort-circu it cu rren t of the m od u l e u n d er test an d m ean s for m on itorin g th e fl ow of cu rren t th rou g h th e m od u l e, th rou g h ou t th e test 0.1 8.3 Procedure a) Electrical l y sh ort an y blocking d iodes incorporated in the m odu l e b) Determ ine th e rated STC sh ort circuit curren t of th e m odu l e from its label or instruction sheet c) Measure th e tem perature an d voltage of th e bypass d iod es d uring th e test d) Con nect wires of th e man ufacturer’s m in im um recom m end ed wire gau ge to th e output term inals of th e m od u le Follow th e m anufacturer’s recom m end ations for wire en try in to th e wirin g com partm ent and replace th e wire com partm en t cover N OTE Som e m odu l es have overl appi ng bypass d i od e ci rcu i ts I n thi s case, i t m ay be n ecessary to i n stal l a j um per cabl e to assure th at al l of the curren t i s fl owi n g th rou g h on e bypass di od e e) H eat th e m od ul e to 75 ° C ± °C Appl y a current to th e m od ul e eq u al to the sh ort circuit curren t of the m od ul e as m easured at STC ± % After h m easure th e tem perature an d voltage of each bypass d iod e f) U sin g th e inform ation provid ed by th e diode m anufacturer, calcu late th e ju nction tem perature from the m easured case tem perature an d the power d issipated in the d iod e usin g the fol lowin g form ul a Tj = Tcase + R TH j c × VD × ID wh ere Tj Tcase R TH j c VD ID = = = = = Diode j unction tem perature Measure d iod e case tem perature Manufacturer’s val ue rel atin g j unction tem perature to case tem perature Diode vol tage Diode curren t N OTE I f the m odu l e contai ns a heat si n k speci fi cal l y d esi gned to red u ce th e operati ng tem peratu re of th e di od e, th i s test m ay be perform ed at th e tem peratu re th e heat si nk reach es u n der di ti ons of 000 W ⋅ m –2 , 43 ° C ± ° C am bi ent wi th no wi nd rath er than at 75 ° C g) I ncrease the appl ied cu rrent to , 25 tim es th e short-circuit curren t of th e m od ule as m easured at STC wh ile m aintain in g th e m od u le tem perature at 75 ° C ± °C Maintain the curren t flow for h h) Verify that the d iode is stil l operational BS EN 61 646:2008 – 38 – 61 646 I EC: 2008 N OTE Di ode operati on can be veri fi ed by su bsequ entl y u si ng the hot-spot test (1 9) 0.1 8.4 Procedu re a) Electrical l y sh ort an y blocking d iodes incorporated in the m odu l e b) Determ ine th e rated STC sh ort circuit curren t of th e m odu l e from its label or instruction sheet c) Con nect th e l ead wire for VD and ID on both d iod e term inals as sh own in Figure d) I t is recom m ended th at the n ections be m ade by th e m odu l e m an ufactu rer + ID + VD –VD –ID Bypass diode cell cell IEC 593/08 N OTE Th e l ead wi re shoul d n ot cau se h eat di ssi pati on from th e term i nal box Figu re – Bypass Diod e Thermal Test e) Put th e m odu le into the cham ber set u p to 30 ° C ± ° C u ntil th e m odu le tem perature reach es saturati on f) Appl y th e pulsed current (pu lse wid th m s) equ al to th e STC short circu it curren t of th e m odu le, m easure the forward voltage VD1 of d iod e g) As the sam e proced ure, m easure VD2 at 50 ° C ± °C h) As the sam e proced ure, m easure VD3 at 70 ° C ± °C i) j) As the sam e proced ure, m easure VD4 at 90 ° C ± °C Then , obtain th e VD versus Tj characteristic by a l east-squ ares-fit curve from VD1 , VD2 , VD3 an d VD4 N OTE Th is certi fi cati on VD versus Tj ch aracteri sti c m ay be provi ded by d i od e m an ufactu rer wi th a m an ufactu rer’ s k) H eat the m odu le to 75 ˚ C ± °C Appl y a cu rren t to the m od ul e equ al to th e short circuit curren t of the m odu le as m easured at STC ± % After one h our m easure th e forward voltage of th e each d iod es l) U sin g the VD versus Tj characteristic obtain ed in item j ), obtain Tj of th e d iod e d uring th e test in k) m ) I ncrease the appl ied cu rrent to , 25 tim es th e short-circuit curren t of th e m od u le as m easured at STC wh il e m aintain in g the m od ul e tem perature at 75 °C ± °C n) Maintain th e current fl ow for h o) Verify that the d iode is stil l operational after com pl eting th is test 1 8.5 Final M easurements Repeat tests 1 and BS EN 61 646:2008 61 646 I EC: 2008 1 8.6 – – – – – 39 – Re q u i re m e n t s The d iode j u nction tem perature as d eterm in ed in 1 f) or 1 l) shal l not exceed th e d iod e m anufacturer’s m axim um j unction tem perature rating “for tin uous operation” N o evid ence of m aj or visual d efects, as defin ed in Cl ause I nsu lation resistance sh al l m eet the sam e req uirem ents as for th e in itial m easurem ents The d iod e sh al l stil l fu nction as a d iod e after th e concl usion of th e test 0.1 0.1 9.1 L i g h t-s o a ki n g P u rp o s e To stabil ise th e electrical characteristics of thin-fil m m odul es by m eans of natural sun l igh t or sim ul ated solar irrad iation 0.1 9.2 Ap p a tu s a) A cl ass CCC sol ar sim ul ator, in accord ance with th e I EC 60904-9, or natural su n l ight b) A su itable reference d evice, with in tegrator, for m on itorin g th e irrad iation c) Means to m ou nt the m odu l es, as recom m end ed by th e m anufacturer, co-plan ar with th e reference d evice d) Means for m easurin g the tem perature of the m od u le(s) to an accuracy of ±1 ° C e) Resisti ve l oad s si zed su ch th at at STC th e m od u l es wi l l operate n ear th eir m axim um power poi n t 0.1 9.3 P ro ce d u re a) Attach th e resisti ve l oad s to th e m od ul es an d m ount th em , as recom m ended by the m anufacturer, with th e reference d evice in th e test plan e of th e sim u lator b) When using a sol ar sim u lator, use th e reference device to set th e irrad iance between 600 W ⋅ m –2 an d 000 W ⋅ m –2 Record th e irrad ian ce c) During th e sim ul ator exposure, m od u le tem peratures m ust stay in th e ran ge 50 ° C ± °C d) Subj ect each m odu le to irradiation until its m aximum power valu e stabil izes Stabil ization occurs wh en m easurem en ts from two consecu tive periods of at least 43 kWh ⋅ m –2 each integrated over periods wh en th e tem perature is between 40 ° C an d 60 o C, m eet th e fol l owing criteria: ( Pm ax – Pm i n )/P averag e < % All in term ediate m axim um power m easurem ents shal l be perform ed at an y ven ient m od u le tem perature reproduced within ±2 ° C e) Report the irrad iation at wh ich th is stabil ity is reached 1 9.4 F i n a l m e a s u re m e n ts Repeat tests 1 , and (Perform ance at STC) 1 9.5 – – – Re q u i re m e n t s N o evid ence of m aj or visual d efects, as defin ed in Cl ause I nsu lation resistance sh al l m eet the sam e req uirem ents as for th e in itial m easurem ents After the final l igh t-soaking, the m axim um outpu t power at STC sh al l be n ot l ess than 90 % of th e m in im um val u e specified by th e m an ufacturer in Clause (See Cl au se ) BS EN 61 646:2008 – 40 – 61 646 I EC: 2008 Bibliograph y I EC 60904-5, Ph o to vo lta ic de vice s – Pa rt 5: D e te rm in a tio n o f e q uiva le n t ce ll te m p e ture (ECT) o f p h o to vo lta ic (PV) de vice s b y th e o p e n - c ircu it vo lta ge m e th o d I EC 60904-8, Ph o to vo lta ic de vice s – Pa rt 8: Me a sure m e n t of s p e c tra l re sp o n s e of a p h o to vo lta ic (PV) de vice I EC 61 853, Pe rfo rm a n ce te s tin g a n d e n e rgy tin g o f te rre s tria l p h o to vo lta ic (PV) m o du le s _ ————————— U n d er si d erati on This page deliberately left blank NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW British Standards Institution (BSI) BSI is the national body responsible for preparing British Standards and other 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