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ASTM E1040-10(2020)

(Specification)

Standard Specification for Physical Characteristics of Nonconcentrator Terrestrial Photovoltaic Reference Cells

Standard Specification for Physical Characteristics of Nonconcentrator Terrestrial Photovoltaic Reference Cells

ABSTRACT
This specification describes the physical requirements for primary and secondary nonconcentrator terrestrial phorovoltaic reference cells based on small-cell package design and module-package design. These requirements include those for product marking, reference cell material, window, configuration, electrical connectors, and temperature sensor.
SCOPE
1.1 This specification describes the physical requirements for primary and secondary terrestrial nonconcentrator photovoltaic reference cells. A reference cell is defined as a device that meets the requirements of this specification and is calibrated in accordance with Test Method E1125 or Test Method E1362.  
1.2 Reference cells are used in the determination of the electrical performance of photovoltaic devices, as stated in Test Methods E948 and E1036.  
1.3 Two reference cell physical specifications are described:  
1.3.1 Small-Cell Package Design—A small, durable package with a low thermal mass, wide optical field-of-view, and standardized dimensions intended for photovoltaic devices up to 20 by 20 mm, and  
1.3.2 Module-Package Design—A package intended to simulate the optical and thermal properties of a photovoltaic module design, but electric connections are made to only one photovoltaic cell in order to eliminate problems with calibrating series and parallel connections of cells. Physical dimensions are not standardized.  
1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

General Information

Status
Published
Publication Date
31-May-2020
ICS
27.160 - Solar energy engineering
Technical Committee
E44 - Solar, Geothermal and Other Alternative Energy Sources
Drafting Committee
E44.09 - Photovoltaic Electric Power Conversion
Current Stage
Ref Project

Relations

Replaces
ASTM E1040-10(2016) - Standard Specification for Physical Characteristics of Nonconcentrator Terrestrial Photovoltaic Reference Cells
Effective Date
01-Jun-2020
Refers
ASTM E948-16(2020) - Standard Test Method for Electrical Performance of Photovoltaic Cells Using Reference Cells Under Simulated Sunlight
Effective Date
01-Jun-2020
Refers
ASTM E1036-15(2019) - Standard Test Methods for Electrical Performance of Nonconcentrator Terrestrial Photovoltaic Modules and Arrays Using Reference Cells
Effective Date
01-Apr-2019
Refers
ASTM E1362-15(2019) - Standard Test Methods for Calibration of Non-Concentrator Photovoltaic Non-Primary Reference Cells
Effective Date
01-Apr-2019
Refers
ASTM E948-16 - Standard Test Method for Electrical Performance of Photovoltaic Cells Using Reference Cells Under Simulated Sunlight
Effective Date
01-Nov-2016
Refers
ASTM E1125-16 - Standard Test Method for Calibration of Primary Non-Concentrator Terrestrial Photovoltaic Reference Cells Using a Tabular Spectrum
Effective Date
01-Jul-2016
Refers
ASTM E1362-15 - Standard Test Methods for Calibration of Non-Concentrator Photovoltaic Non-Primary Reference Cells
Effective Date
01-Dec-2015
Refers
ASTM E1125-10(2015) - Standard Test Method for Calibration of Primary Non-Concentrator Terrestrial Photovoltaic Reference Cells Using a Tabular Spectrum
Effective Date
01-Mar-2015
Refers
ASTM E948-15 - Standard Test Method for Electrical Performance of Photovoltaic Cells Using Reference Cells Under Simulated Sunlight
Effective Date
01-Feb-2015
Refers
ASTM E1036-15 - Standard Test Methods for Electrical Performance of Nonconcentrator Terrestrial Photovoltaic Modules and Arrays Using Reference Cells
Effective Date
01-Feb-2015
Refers
ASTM E772-13 - Standard Terminology of Solar Energy Conversion
Effective Date
01-Sep-2013
Refers
ASTM E1036-12 - Standard Test Methods for Electrical Performance of Nonconcentrator Terrestrial Photovoltaic Modules and Arrays Using Reference Cells
Effective Date
01-Dec-2012
Refers
ASTM E772-11 - Standard Terminology of Solar Energy Conversion
Effective Date
01-Sep-2011
Refers
ASTM E1125-10 - Standard Test Method for Calibration of Primary Non-Concentrator Terrestrial Photovoltaic Reference Cells Using a Tabular Spectrum
Effective Date
01-Jun-2010
Refers
ASTM E1362-10 - Standard Test Method for Calibration of Non-Concentrator Photovoltaic Secondary Reference Cells
Effective Date
01-Jan-2010

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ASTM E1040-10(2020) - Standard Specification for Physical Characteristics of Nonconcentrator Terrestrial Photovoltaic Reference CellsASTM E1040-10(2020) - Standard Specification for Physical Characteristics of Nonconcentrator Terrestrial Photovoltaic Reference Cells
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ASTM E1040-10(2020) - Standard Specification for Physical Characteristics of Nonconcentrator Terrestrial Photovoltaic Reference Cells
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This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: E1040 −10 (Reapproved 2020) An American National Standard
Standard Specification for
Physical Characteristics of Nonconcentrator Terrestrial
Photovoltaic Reference Cells
This standard is issued under the fixed designation E1040; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 2. Referenced Documents
1.1 This specification describes the physical requirements 2.1 ASTM Standards:
for primary and secondary terrestrial nonconcentrator photo- E772 Terminology of Solar Energy Conversion
voltaic reference cells. A reference cell is defined as a device E948 Test Method for Electrical Performance of Photovol-
that meets the requirements of this specification and is cali- taic Cells Using Reference Cells Under Simulated Sun-
brated in accordance with Test Method E1125 or Test Method light
E1362. E1036 Test Methods for Electrical Performance of Noncon-
centrator Terrestrial Photovoltaic Modules and Arrays
1.2 Reference cells are used in the determination of the
Using Reference Cells
electricalperformanceofphotovoltaicdevices,asstatedinTest
E1125 Test Method for Calibration of Primary Non-
Methods E948 and E1036.
Concentrator Terrestrial Photovoltaic Reference Cells Us-
1.3 Two reference cell physical specifications are described:
ing a Tabular Spectrum
1.3.1 Small-Cell Package Design—A small, durable pack-
E1328 Terminology Relating to Photovoltaic Solar Energy
age with a low thermal mass, wide optical field-of-view, and
Conversion (Withdrawn 2012)
standardized dimensions intended for photovoltaic devices up
E1362 Test Methods for Calibration of Non-Concentrator
to 20 by 20 mm, and
Photovoltaic Non-Primary Reference Cells
1.3.2 Module-Package Design—A package intended to
2.2 Military Specification Sheet:
simulate the optical and thermal properties of a photovoltaic
MS3106C Connector, Plug, Electric, Straight, Solder
module design, but electric connections are made to only one
Contracts, AN Type
photovoltaic cell in order to eliminate problems with calibrat-
ing series and parallel connections of cells. Physical dimen-
3. Terminology
sions are not standardized.
3.1 Definitions—For definitions of terms used in this
1.4 The values stated in SI units are to be regarded as
specification, see Terminologies E772 and E1328.
standard. No other units of measurement are included in this
standard.
4. Classification
1.5 This standard does not purport to address all of the
4.1 Two types of reference cells are used in the evaluation
safety concerns, if any, associated with its use. It is the
of the electrical performance of photovoltaic terrestrial de-
responsibility of the user of this standard to establish appro-
vices:
priate safety, health, and environmental practices and deter-
4.1.1 Primary Reference Cells—Reference cells calibrated
mine the applicability of regulatory limitations prior to use.
directly in sunlight in accordance with Test Method E1125.
1.6 This international standard was developed in accor-
4.1.2 Secondary Reference Cells—Reference cells cali-
dance with internationally recognized principles on standard-
brated against a primary reference cell in accordance with Test
ization established in the Decision on Principles for the
Method E1362.
Development of International Standards, Guides and Recom-
mendations issued by the World Trade Organization Technical
Barriers to Trade (TBT) Committee.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
This specification is under the jurisdiction of ASTM Committee E44 on Solar, Standards volume information, refer to the standard’s Document Summary page on
Geothermal and OtherAlternative Energy Sources and is the direct responsibility of the ASTM website.
Subcommittee E44.09 on Photovoltaic Electric Power Conversion. The last approved version of this historical standard is referenced on
CurrenteditionapprovedJune1,2020.PublishedJuly2020.Originallyapproved www.astm.org.
in 1984. Last previous edition approved in 2016 as E1040 – 10 (2016). DOI: Available from Superintendent of Documents, U.S. Government Printing
10.1520/E1040-10R20. Office, N. Capital and H Streets, NW, Washington, DC 20401.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
E1040 − 10 (2020)
4.2 Thetwotypesarenotphysicallyorelectricallydifferent, are (1) an electrically and thermally conductive body with a
butaredifferentintheirmannerofcalibration.Hereafterinthis lowthermalmass, (2)standardizedmountingholes, (3)detach-
specification, both types of reference cells will be considered ablecablesusingstandardizedfemaleconnectorsonthesideof
alike and referred to only as reference cells. the package, (4) standardized temperature sensors, (5) a flat
rear surface without protrusions, (6) permanent identification
5. Materials and Manufacture
markings, and (7) standardized internal wiring.
5.2.2 Reference Cell Material—The WPVS design specifies
5.1 Requirements for Both Reference Cell Designs:
a monocrystalline float-zone Si solar cell because device
5.1.1 Product Marking— A label, identification mark, or
stability and quality are desirable for the primary reference
serial number shall be permanently stamped or scribed on the
cells that constitute the WPVS. For other applications, addi-
reference-cell holder. This product marking shall identify the
tional considerations may be more important and therefore the
device for reference to other documentation containing elec-
float-zone Si solar cell can be replaced with alternative device
trical and mechanical data, including information such as the
types as required, such as polycrystalline Si or GaAs.
cell material and manufacturer.
5.2.3 Window—The WPVS specifies a “durable, sm
...

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4.4 Fig. 1 illustrates the hot spot effect in a module of a series string of cells, one of which, cell Y, is partially shadowed. The amount of electrical power dissipated in Y is equal to the product of the module current and the reverse voltage developed across Y. For any irradiance level, when the reverse voltage across Y is equal to the voltage generated by the remaining (s-1) cells in the module, power dissipation is at a maximum when the module is short-circuited. This is shown in Fig. 1 by the shaded rectangle constructed at the intersection of the reverse I-V characteristic of Y with the image of the forward I-V characteristic of the (s-1) cells.
FIG. 1 Hot Spot Effect  
4.5 Bypass diodes, if present, as shown in Fig. 2, begin conducting when a series-connected string in a module is in reverse bias, thereby limiting the power dissipation in the reduced-output cell.  
FIG. 2 Bypass Diode Effect  
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1.1 This test method provides a procedure to determine the ability of a photovoltaic (PV) module to endure the long-term effects of periodic “hot spot” heating associated with common fault conditions such as severely cracked or mismatched cells, single-point open circuit failures (for example, interconnect failures), partial (or nonuniform) shadowing, or soiling. Such effects typically include solder melting or deterioration of the encapsulation, but in severe cases could progress to combustion of the PV module and surrounding materials.  
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1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
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ASTM E781-86(2023)(Practice)
Standard Practice for Evaluating Absorptive Solar Receiver Materials When Exposed to Conditions Simulating Stagnation in Solar Collectors with Cover Plates

SIGNIFICANCE AND USE
4.1 Although this practice is intended for evaluating solar absorber materials and coatings used in flat-plate collectors, no single procedure can duplicate the wide range of temperatures and environmental conditions to which these materials may be exposed during in-service conditions.  
4.2 This practice is intended as a screening test for absorber materials and coatings. All conditions are chosen to be representative of those encountered in solar collectors with single cover plates and with no added means of limiting the temperature during stagnation conditions.  
4.3 This practice uses exposure in a simulated collector with a single cover plate. Although collectors with additional cover plates will produce higher temperatures at stagnation, this procedure is considered to provide adequate thermal testing for most applications.
Note 1: Mathematical modeling has shown that a selective absorber, single glazed flat-plate solar collector can attain absorber plate stagnation temperatures as high as 226 °C (437 °F) with an ambient temperature of 37.8 °C (100 °F) and zero wind velocity, and a double glazed one as high as 245 °C (482 °F) under these conditions. The same configuration solar collector with a nonselective absorber can attain absorber stagnation temperatures as high as 146 °C (284 °F) if single glazed, and 185 °C (360 °F) if double glazed, with the same environmental conditions (see “Performance Criteria for Solar Heating and Cooling Systems in Commercial Buildings,” NBS Technical Note 1187).4  
4.4 This practice evaluates the thermal stability of absorber materials. It does not evaluate the moisture stability of absorber materials used in actual solar collectors exposed outdoors. Moisture intrusion into solar collectors is a frequent occurrence in addition to condensation caused by diurnal breathing.  
4.5 This practice differentiates between the testing of spectrally selective absorbers and nonselective absorbers.  
4.5.1 Testing Spectrally Selective...
SCOPE
1.1 This practice covers a test procedure for evaluating absorptive solar receiver materials and coatings when exposed to sunlight under cover plate(s) for long durations. This practice is intended to evaluate the exposure resistance of absorber materials and coatings used in flat-plate collectors where maximum non-operational stagnation temperatures will be approximately 200 °C (392 °F).  
1.2 This practice shall not apply to receiver materials used in solar collectors without covers (unglazed) or in evacuated collectors, that is, those that use a vacuum to suppress convective and conductive thermal losses.  
1.3 The values stated in SI units are to be regarded as the standard.  
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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ASTM
ASTM E822-92(2023)(Practice)
Standard Practice for Determining Resistance of Solar Collector Covers to Hail by Impact with Propelled Ice Balls

SIGNIFICANCE AND USE
2.1 In many geographic areas there is concern about the effect of falling hail upon solar collector covers. This practice may be used to determine the ability of flat-plate solar collector covers to withstand the impact forces of hailstones. In this practice, the ability of a solar collector cover plate to withstand hail impact is related to its tested ability to withstand impact from ice balls. The effects of the impact on the material are highly variable and dependent upon the material.  
2.2 This practice describes a standard procedure for mounting the test specimen, conducting the impact test, and reporting the effects.  
2.2.1 The procedures for mounting cover plate materials and collectors are provided to ensure that they are tested in a configuration that relates to their use in a solar collector.  
2.2.2 The corner locations of the four impacts are chosen to represent vulnerable sites on the cover plate. Impacts near corner supports are more critical than impacts elsewhere. Only a single impact is specified at each of the impact locations. For test control purposes, multiple impacts in a single location are not permitted because a subcritical impact may still cause damage that would alter the response to subsequent impacts.  
2.2.3 Resultant velocity is used to simulate the velocity that may be reached by hail accompanied by wind. The resultant velocity used in this practice is determined by vector addition of a 20 m/s (45 mph) horizontal velocity to the vertical terminal velocity.  
2.2.4 Ice balls are used in this practice to simulate hailstones because natural hailstones are not readily available to use, and ice balls closely approximate hailstones. However, no direct relationship has been established between the effect of impact of ice balls and hailstones. Hailstones are highly variable in properties such as shape, density, and frangibility.2 These properties affect factors such as the kinetic energy delivered to the cover plate, the period during ...
SCOPE
1.1 This practice covers a procedure for determining the ability of cover plates for flat-plate solar collectors to withstand impact forces of falling hail. Propelled ice balls are used to simulate falling hailstones. This practice is not intended to apply to photovoltaic cells or arrays.  
1.2 This practice defines two types of test specimens, describes methods for mounting specimens, specifies impact locations on each test specimen, provides an equation for determining the velocity of any size ice ball, provides a method for impacting the test specimens with ice balls, and specifies parameters that must be recorded and reported.  
1.3 This practice does not establish pass or fail levels. The determination of acceptable or unacceptable levels of ice-ball impact resistance is beyond the scope of this practice.  
1.4 The size of ice ball to be used in conducting this test is not specified in this practice. This practice can be used with various sizes of ice balls.  
1.5 The categories of solar collector cover plate materials to which this practice may be applied cover the range of:  
1.5.1 Brittle sheet, such as glass,  
1.5.2 Semirigid sheet, such as plastic, and  
1.5.3 Flexible membrane, such as plastic film.  
1.6 Solar collector cover materials should be tested as:  
1.6.1 Part of an assembled collector (Type 1 specimen), or  
1.6.2 Mounted on a separate test frame cover plate holder (Type 2 specimen).  
1.7 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.  
1.8 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.9 This international standard was developed in accordance with internatio...

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ASTM
ASTM E881-92(2022)(Practice)
Standard Practice for Exposure of Solar Collector Cover Materials to Natural Weathering Under Conditions Simulating Stagnation Mode

SIGNIFICANCE AND USE
4.1 This practice describes a weathering box test fixture and establishes limits for the heat loss coefficients. Uniform exposure guidelines are provided to minimize the variables encountered during outdoor exposure testing.  
4.2 Since the combination of elevated temperature and solar radiation may cause some solar collector cover materials to degrade more rapidly than either exposure alone, a weathering box that elevates the temperature of the cover materials is used.  
4.3 This practice may be used to assist in the evaluation of solar collector cover materials in the stagnation mode. No single temperature or procedure can duplicate the range of temperatures and environmental conditions to which cover materials may be exposed during stagnation conditions. To assist in evaluation of solar collector cover materials in the operational mode, Practice E782 should be used. Insufficient data exist to obtain exact correlation between the behavior of materials exposed in accordance with this practice and actual in-service performance.  
4.4 This practice may also be useful in comparing the performance of different materials at one site or the performance of the same material at different sites, or both.  
4.5 Means of evaluating the effects of weathering are provided in Practice E765, and in other ASTM test methods that evaluate material properties.  
4.6 Exposures of the type described in this practice may be used to evaluate the stability of solar collector cover materials when exposed outdoors to the varied influences that comprise weather. Exposure conditions are complex and changeable. Important factors are material temperature, climate, time of year, presence of industrial pollution, etc. Generally, because it is difficult to define or measure precisely the factors influencing degradation due to weathering, results of outdoor exposure tests must be taken as indicative only. Repeated exposure testing at different seasons over a period of more than one year is req...
SCOPE
1.1 This practice covers a procedure for the exposure of solar collector cover materials to the natural weather environment at elevated temperatures that approximate stagnation conditions in solar collectors having a combined back and edge loss coefficient of less than 1.5 W/(m2·°C).  
1.2 This practice is suitable for exposure of both glass and plastic solar collector cover materials. Provisions are made for exposure of single and double cover assemblies to accommodate the need for exposure of both inner and outer solar collector cover materials.  
1.3 This practice does not apply to cover materials for evacuated collectors, photovoltaic cells, flat-plate collectors having a combined back and edge loss coefficient greater than 1.5 W/(m2·°C), or flat-plate collectors whose design incorporates means for limiting temperatures during stagnation.  
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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ASTM
ASTM E782-95(2022)(Practice)
Standard Practice for Exposure of Cover Materials for Solar Collectors to Natural Weathering Under Conditions Simulating Operational Mode

SIGNIFICANCE AND USE
3.1 This practice describes a weathering box test fixture and provides uniform exposure guidelines to minimize the variables encountered during outdoor exposure testing.  
3.2 This practice may be useful in comparing the performance of different materials at one site or the performance of the same material at different sites, or both.  
3.3 Since the combination of elevated temperature and solar radiation may cause some solar collector cover materials to degrade more rapidly than either alone, a weathering box that elevates the temperature of the cover materials is used.  
3.4 This practice is intended to assist in the evaluation of solar collector cover materials in the operational, not stagnation mode. Insufficient data exist to obtain exact correlation between the behavior of materials exposed according to this practice and actual in-service performance.  
3.5 Means of evaluation of effects of weathering are provided in Practice E781, and in other ASTM test methods that evaluate material properties.  
3.6 Tests of the type described in this practice may be used to evaluate the stability of solar collector cover materials when exposed outdoors to the varied influences which comprise weather. Exposure conditions are complex and changeable. Important factors are solar radiation, temperature, moisture, time of year, presence of pollutants, etc. These factors vary from site to site and should be considered in selecting locations for exposure. Control samples must always be used in weathering tests for comparative analysis. Outdoor exposure for at least two years is required to make evident changes, such as surface degradation without the use of sophisticated analytical equipment.  
3.7 Temperature conditions attained with this box may not exactly duplicate those that occur under operational conditions with fluid flow. Dependent on environmental exposure conditions, the cover plate temperatures obtained with this box may be higher or lower than those obtained und...
SCOPE
1.1 This practice provides a procedure for the exposure of cover materials for flat-plate solar collectors to the natural weather environment at temperatures that are elevated to approximate operating conditions.  
1.2 This practice is suitable for exposure of both glass and plastic solar collector cover materials. Provisions are made for exposure of single and double cover assemblies to accommodate the need for exposure of both inner and outer solar collector cover materials.  
1.3 This practice does not apply to cover materials for evacuated collectors or photovoltaics.  
1.4 The values stated in SI units are to be regarded as the standard.  
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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