ASTM E1462-2000(2006) Standard Test Methods for Insulation Integrity and Ground Path Continuity of Photovoltaic Modules《光电器件模块的完整性绝缘和连续地面路径的标准试验方法》.pdf

1、Designation: E 1462 00 (Reapproved 2006)Standard Test Methods forInsulation Integrity and Ground Path Continuity ofPhotovoltaic Modules1This standard is issued under the fixed designation E 1462; the number immediately following the designation indicates the year oforiginal adoption or, in the case

2、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 These test methods cover procedures for (1) testing forcurrent leakage between the electrica

3、l circuit of a photovoltaicmodule and its external components while a user-specifiedvoltage is applied and (2) for testing for possible moduleinsulation breakdown (dielectric voltage withstand test).1.2 A procedure is described for measuring the insulationresistance between the electrical circuit of

4、 a photovoltaicmodule and its external components (insulation resistance test).1.3 A procedure is provided for verifying that electricalcontinuity exists between the exposed external conductivesurfaces of the module, such as the frame, structural members,or edge closures, and its grounding point (gr

5、ound path conti-nuity test).1.4 This test method does not establish pass or fail levels.The determination of acceptable or unacceptable results isbeyond the scope of this test method.1.5 There is no similar or equivalent ISO standard.1.6 This standard does not purport to address all of thesafety con

6、cerns, 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:2E 772 Terminology Relating to Solar En

7、ergy ConversionE 1328 Terminology Relating to Photovoltaic Solar EnergyConversion2.2 Underwriters Laboratories Standard:3ANSI/UL 1703 Standard for Safety for Flat-Plate Photo-voltaic Modules and Panels3. Terminology3.1 DefinitionsDefinitions of terms used in this testmethod may be found in Terminolo

8、gies E 772 and E 1328.3.2 Definitions of Terms Specific to This Standard:3.2.1 ground path continuitythe electrical continuity be-tween the external and conductive surfaces of a photovoltaicmodule and the intended grounding point of the module.3.2.2 insulation resistancethe electrical resistance of

9、aphotovoltaic module insulation, measured at a specified ap-plied voltage between the module internal circuitry and itsgrounding point or mounting structure.3.2.3 maximum system voltagethe maximum electricalpotential, referenced at the system grounding point, that can begenerated by a photovoltaic p

10、ower system as specified by themodel manufacturer.4. Summary of Test Method4.1 Insulation IntegrityTwo procedures are provided fortesting the isolation of the electrically active parts of themodule from the accessible conductive parts and the exposednonconductive surfaces. This isolation is necessar

11、y to providefor safe insulation, use, and service of a photovoltaic module orsystem.4.1.1 Dielectric Voltage Withstand ProcedureA rampedvoltage is applied between the photovoltaic circuit and theaccessible parts and surfaces of the module outside of thephotovoltaic circuit while monitoring the curre

12、nt, or by deter-mining whether the leakage current exceeds a predeterminedlimit. The module is then inspected for evidence of possiblearcing.4.1.2 Insulation Resistance ProcedureThe insulation re-sistance is measured between the photovoltaic circuit and theaccessible parts and surfaces of the module

13、 outside of thephotovoltaic circuit, using a high-impedance ohmmeter.4.2 Ground Path Continuity ProcedureThis procedure isintended for verification that electrical continuity exists be-tween all of the external conductive components and themodule grounding point specified by the manufacturer. This i

14、s1These test methods are under the jurisdiction of ASTM Committee E44 onSolar, Geothermal, and Other Alternative Energy Sources and is the directresponsibility of Subcommittee E44.09 on Photovoltaic Electric Power Conversion.Current edition approved March 1, 2006. Published March 2006. Originallyapp

15、roved in 1992. Last previous edition approved in 2000 as E 1462-00.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM we

16、bsite.3Underwriters Laboratories Incorporated, Publication Stock, 333 PfingstenRoad, Northbrook, IL 60062.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.accomplished by passing a current between the groundingterminal or lead and the

17、 conductive part in question andcalculating the resistance between these two points.5. Significance and Use5.1 The design of a photovoltaic module or system intendedto provide safe conversion of the suns radiant energy intouseful electricity must take into consideration the possibility ofhazard shou

18、ld the user come into contact with the electricalpotential of the module. These test methods describe proce-dures for verifying that the design and construction of themodule or system are capable of providing protection fromshock through normal installation and use. At no location onthe module shoul

19、d this electrical potential be accessible, withthe obvious exception of the intended output leads.5.2 These test methods describe procedures for determiningthe ability of the module to provide protection from electricalhazards.5.3 These procedures may be specified as part of a series ofqualification

20、 tests involving environmental exposure, mechani-cal stress, electrical overload, or accelerated life testing.5.4 These procedures are normally intended for use on drymodules; however, the test modules may be either wet or dry,as indicated by the appropriate protocol.5.5 These procedures may be used

21、 to verify module assem-bly on a production line.5.6 Insulation resistance and leakage current are strongfunctions of module dimensions, ambient relative humidity andabsorbed water vapor, and the ground path continuity proce-dure is strongly affected by the location of contacts and testleads to the

22、module frame and grounding points.5.6.1 For these reasons, it is the responsibility of the user ofthese test methods to specify the maximum acceptable leakagecurrent for the dielectric voltage withstand test, and themaximum acceptable resistance for the ground path continuityprocedure.5.6.2 Fifty A

23、has been commonly used as the maximumacceptable leakage current (see ANSI/UL 1703, Section 26.1),and 0.1 V has been commonly used as the maximum accept-able resistance.5.7 Some module designs may not use any external metalliccomponents and thus lack a ground point designated by themodule manufacture

24、r. In these cases, the ground path continu-ity test is not applicable.6. Apparatus6.1 Variable d-c Voltage Power SupplyFor the dielectricvoltage withstand test, a d-c voltage power supply capable ofproviding the specified test voltage (see 5.6) in a gradual andsmooth manner is required. The applicat

25、ion of voltage must notallow transients that may cause the instantaneous voltage toexceed the specified test voltage; nor may the flow of capaci-tive current, due to charging, cause the test to indicate anerroneous leakage current.6.1.1 The power supply must include a means of indicatingthe test vol

26、tage that is applied to the module.6.1.2 The output voltage of the power supply must becontinuously adjustable and may have an automatically con-trolled ramp rate.6.1.3 The power supply must be capable, as a minimum, ofdetecting a leakage current of 1 A.6.1.4 The power supply may, as an option, incl

27、ude a leakagecurrent limit set-point that will shut down the power supplywhen the leakage current exceeds the set-point. Audible orvisual alarms which indicate that the leakage current hasexceeded the set-point are also acceptable.6.2 Ground Path Continuity Tester, for measuring the resis-tance betw

28、een any accessible conductive frame or supportelement and the module grounding point, with a minimumresolution of 0.01 V.6.2.1 The tester must be capable of passing a current oftwice the module short-circuit current through the moduleground path being tested.6.2.2 The tester must be able to limit th

29、e power applied to amodule ground path to 500 W.6.3 OhmmeterA high-impedance ohmmeter, or similardevice, capable of measuring a minimum of 1000 MV, and canprovide a voltage suitable for measuring high-resistances.6.4 Metallic Contact(s), aluminum or other metallic foil, ora rigid metallic plate, pla

30、ced on the surfaces of moduleslacking a metallic frame. The metallic contact(s) function as asubstitute for a metallic frame.6.5 Test Stand, for holding modules during testing.7. Procedures7.1 Procedure AInsulation Integrity, Dielectric VoltageWithstand:7.1.1 Mount the module to be tested on the tes

31、t stand andensure that the module is not illuminated. This may beaccomplished by placing it face down on the test stand or byshading the face of the module with an appropriately sizedopaque material.7.1.2 Short the output leads of the module together.7.1.3 Ensure that the power supply is turned off

32、before anyelectrical connections are made.7.1.4 Connect the high potential output of the power supplyto the module output leads.7.1.5 Connect the grounded output of the power supply tothe module grounding point or specific component beingtested.7.1.5.1 The module may contain separate and unconnected

33、metallic components; if so, the procedure must be repeated foreach metallic component. For example, a junction box notconnected to the frame must be tested separately.7.1.5.2 Any connections to metallic components must bemade to uninsulated points for the procedure to be valid. Forexample, an anodiz

34、ed aluminum frame would not qualifyunless the anodization was removed at the test point.7.1.5.3 If the module lacks any exterior metallic compo-nents, the leakage current connection must be made to aninsulating surface such as a nonmetallic module frame. Ametallic contact (see 6.4) must be placed in

35、 contact with thesurface, and connection is then made to the metallic contact.The contact must be at least the same size as the surface beingtested. The sponsor or user of this procedure must specifyacceptable connections in these cases.7.1.6 Determine the test voltage for the dielectric voltagewith

36、stand test. The maximum system voltage for which aE 1462 00 (2006)2module is suitable must be specified by the module manufac-turer. The test voltage shall be twice the maximum systemvoltage plus 1000 V. For a module with a maximum systemvoltage of 30 volts or less, the test voltage shall be 500 vol

37、ts.7.1.7 Increase the voltage, not to exceed a rate of 200 V/s,until the test voltage is achieved.NOTE 1The capacitance of modules may be large enough to causelarge currents to flow while the insulation capacitance is charging. Theoperator must be aware of such conditions and allow time for the curr

38、entto stabilize.7.1.8 Hold the power supply voltage at the test voltage for1 min.7.1.9 Record the maximum leakage current, or the voltageat which the leakage current set-point was exceeded.7.1.9.1 If the equipment has the current limit set-pointcapability described in 6.1.4 and the power supply shut

39、s downor the alarms are triggered, the maximum current leakage hasbeen exceeded.7.1.10 Observe and listen to the module during the test forevidence of arcing or flash-over.7.1.11 Turn off the power supply.7.1.12 Reverse the power supply-to-module connection po-larity (see 7.1.4 and 7.1.5) and repeat

40、 7.1.7 through 7.1.11.7.1.13 Disconnect the test module.7.1.14 Inspect the module for any visual evidence of arcingor flash-over.7.2 Procedure BInsulation Integrity, Insulation Resis-tance:7.2.1 Mount the module as specified in 7.1.1 and 7.1.2.7.2.2 Connect the ohmmeter to the module as specified in

41、7.1.3-7.1.5 with references to the power supply replaced withthe ohmmeter.7.2.3 Measure and record the insulation resistance indicatedby the ohmmeter.7.3 Procedure CGround Path Continuity:7.3.1 Determine the necessary current to pass through anymodule ground paths. This current is equal to twice the

42、 moduleshort-circuit current.7.3.2 Determine the location of the grounding point and allaccessible conductive parts of the module. Establish thecontact size, location, and attachment method necessary toperform the ground path continuity test.7.3.2.1 A conductive part is considered accessible unless

43、itis insulated with a material that has been evaluated for itsinsulation properties in the intended application or it isphysically inaccessible according to the definition in ANSI/UL1703, Section 14.7.3.2.2 If the module has more than one accessible conduc-tive part, each must be tested separately.7

44、.3.3 Connect the grounded lead of the continuity tester tothe module grounding point identified by the module manu-facturer.7.3.4 Connect the the high potential lead of the continuitytester to an accessible conductive part of the module.7.3.5 Increase the voltage applied by the continuity testerfrom

45、 zero until a current of twice the module short-circuitcurrent is passing through the grounding path under test, oruntil the maximum wattage indicated in 6.2.2 is reached.7.3.6 Compute and record the resistance from the voltagedrop across the continuity tester leads at the points at whichthey connec

46、t to the module.7.3.7 Repeat 7.3.4-7.3.6 for each ground path identified in7.3.2.8. Report8.1 Report the following items at the minimum:8.1.1 The manufacturer and a complete test specimen iden-tification,8.1.2 A description of the module construction,8.1.3 A description of the measurement equipment

47、andmeasurement conditions or parameters,8.1.4 A description of any apparent changes due to testing,with any sketches or photographs providing clarification,8.1.5 The actual maximum leakage current observed (7.1.9)or the applied voltage at which the maximum current leakagewas exceeded (7.1.9.1),8.1.6

48、 Observations or indications of arcing or flash-over,8.1.7 The insulation resistance recorded in 7.2.3,8.1.8 Results of the ground path continuity procedure from7.3.6, and8.1.9 Any deviation from the procedures.9. Precision and Bias9.1 Several factors make a determination of the precisionand bias fr

49、om results of an interlaboratory study not practicablefor these procedures.9.1.1 Insulation resistance and insulation current leakageare strong functions of ambient relative humidity and absorbedwater vapor.9.1.2 The ground path continuity procedure is affectedstrongly by the location, size, shape, and attachment methodsof contacts and test leads to the module frame and groundingpoints.9.1.3 For these reasons, the user of this test method specifiesacceptable threshold levels for the dielectric voltage withstandand ground path continuity procedures (see 5.6.1).9.2 Preci