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ASTM E1040-98

(Specification)

Standard Specification for Physical Characteristics of Nonconcentrator Terrestrial Photovoltaic Reference Cells

Standard Specification for Physical Characteristics of Nonconcentrator Terrestrial Photovoltaic Reference Cells

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 Method E1039, 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 Methods 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 These reference cells are intended to be used in applications where a significant fraction of the irradiance has incidence angles less than 30°, with respect to normal as defined in Specification E927.
1.5 This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

General Information

Status
Historical
Publication Date
09-Jun-1998
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

Replaced By
ASTM E1040-05 - Standard Specification for Physical Characteristics of Nonconcentrator Terrestrial Photovoltaic Reference Cells
Effective Date
01-Apr-2005
Referred By
ASTM E1362-15(2019) - Standard Test Methods for Calibration of Non-Concentrator Photovoltaic Non-Primary Reference Cells
Effective Date
10-Jun-1998
Referred By
ASTM E1125-16(2020) - Standard Test Method for Calibration of Primary Non-Concentrator Terrestrial Photovoltaic Reference Cells Using a Tabular Spectrum
Effective Date
10-Jun-1998
Referred By
ASTM E2848-13(2023) - Standard Test Method for Reporting Photovoltaic Non-Concentrator System Performance
Effective Date
10-Jun-1998
Referred By
ASTM E1036-15(2019) - Standard Test Methods for Electrical Performance of Nonconcentrator Terrestrial Photovoltaic Modules and Arrays Using Reference Cells
Effective Date
10-Jun-1998
Referred By
ASTM E2236-10(2019) - Standard Test Methods for Measurement of Electrical Performance and Spectral Response of Nonconcentrator Multijunction Photovoltaic Cells and Modules
Effective Date
10-Jun-1998

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ASTM E1040-98 - Standard Specification for Physical Characteristics of Nonconcentrator Terrestrial Photovoltaic Reference CellsASTM E1040-98 - Standard Specification for Physical Characteristics of Nonconcentrator Terrestrial Photovoltaic Reference Cells
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ASTM E1040-98 - Standard Specification for Physical Characteristics of Nonconcentrator Terrestrial Photovoltaic Reference Cells
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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: E 1040 – 98
Standard Specification for
Physical Characteristics of Nonconcentrator Terrestrial
Photovoltaic Reference Cells
This standard is issued under the fixed designation E 1040; 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 (e) 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- E 772 Terminology Relating to Solar Energy Conversion
voltaic reference cells. A reference cell is defined as a device E 927 Specification for Solar Simulation for Terrestrial
that meets the requirements of this specification and is cali- Photovoltaic Testing
brated in accordance with Method E 1039, Test Method E 948 Test Methods for Electrical Performance of Noncon-
E 1125, or Test Method E 1362. centrator Terrestrial Photovoltaic Cells Using Reference
1.2 Reference cells are used in the determination of the Cells
electricalperformanceofphotovoltaicdevices,asstatedinTest E 1036 Test Methods for Electrical Performance of Non-
Methods E 948 and Methods E 1036. concentrator Terrestrial Photovoltaic Modules and Arrays
1.3 Two reference cell physical specifications are described: Using Reference Cells
1.3.1 Small-Cell Package Design—A small, durable pack- E 1039 Test Method for Calibration and Characterization of
age with a low thermal mass, wide optical field-of-view, and Non-Concentrator Terrestrial Photovoltaic Reference Cells
standardized dimensions intended for photovoltaic devices up Under Global Irradiation
to 20 by 20 mm, and E 1125 Test Method for Calibration of Primary Non-
1.3.2 Module-Package Design—A package intended to Concentrator Terrestrial Photovoltaic Reference Cells Us-
simulate the optical and thermal properties of a photovoltaic ing a Tabular Spectrum
module design, but electric connections are made to only one E 1328 Terminology Relating to Photovoltaic Solar Energy
photovoltaic cell in order to eliminate problems with calibrat- Conversion
ing series and parallel connections of cells. Physical dimen- E 1362 Test Method for Calibration of Non-Concentrator
sions are not standardized. Photovoltaic Secondary Reference Cells
1.4 These reference cells are intended to be used in appli- 2.2 Military Specification Sheet:
cations where a significant fraction of the irradiance has MS3106C Connector, Plug, Electric, Straight, Solder Con-
incidence angles less than 30°, with respect to normal as tracts, AN Type
defined in Specification E 927.
3. Terminology
1.5 Units—The values stated in SI units are to be regarded
as the standard. No other units of measurement are included in 3.1 Definitions—For definitions of terms used in this speci-
fication, see Terminologies E 772 and E 1328.
this standard.
1.6 This standard does not purport to address all of the
4. Classification
safety problems, if any, associated with its use. It is the
4.1 Two types of reference cells are used in the evaluation
responsibility of the user of this standard to establish appro-
of the electrical performance of photovoltaic terrestrial de-
priate safety and health practices and determine the applica-
vices:
bility of regulatory limitations prior to use.
4.1.1 Primary Reference Cells—Reference cells calibrated
directly in sunlight in accordance with Method E 1039 or Test
Method E 1125, and
This specification is under the jurisdiction ofASTM Committee E-44 on Solar,
Geothermal,andOtherAlternativeEnergySourcesandisthedirectresponsibilityof
Subcommittee E44.09 on Photovoltaic Electric Power Systems. Annual Book of ASTM Standards, Vol 12.02.
Current edition approved June 10, 1998. Published December 1998. Originally Available from Superintendent of Documents, U.S. Government Printing
published as E 1040 – 84. Last previous edition E 1040 – 93. 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.
E 1040
4.1.2 Secondary Reference Cells—Reference cells cali- reflections that can cause measurement errors. The aluminum
brated against a primary reference cell in accordance with Test surface finish specified in Fig. 1 satisfies this requirement.
Method E 1362. 5.2.3 Bonding Adhesive— Any material used for bonding
4.2 Thetwotypesarenotphysicallyorelectricallydifferent, should be compatible with the photovoltaic cell and not cause
butaredifferentintheirmannerofcalibration.Hereafterinthis electrical or optical degradation of the photovoltaic cell. The
specification, both types of reference cells will be considered material’s physical characteristics should be stable over the
alike and referred to only as reference cells. time of intended use and acceptable for outdoor use.
5.2.4 Field-of-View— The field-of-view f, as defined in
5. Materials and Manufacture
Fig. 1, should be at least 160° to minimize measurement errors
5.1 Requirements for Both Reference Cell Designs:
when non-normal irradiation impinges on the reference cell.
5.1.1 Electrical Connections—The electrical connections to 5.2.5 Window—Useofawindowisrecommendedtoprotect
the photovoltaic cell shall consist of a four-wire contact system
the photovoltaic cell.Acolored glass or other optical filter may
(Kelvin probe), with two wires connected to the top of the top also be used to modify the spectral response of the cell, if
contact of the cell, and two wires to the bottom contact. A
necessary for specific applications.
minimum length of1mof1.0 mm (AWG 18) diameter 5.2.5.1 If a clear window is used, the optical transmission of
four-conductor cable with an ultraviolet-stable outer cover the window should be constant within 61 % in the photovol-
rated for outdoor usage is recommended. The standard electri- taic cell wavelength response band, with a mean transmission
cal connector shall be M
...

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5.1 Because there are a number of choices in this test method that depend on different applications and system configurations, it is the responsibility of the user of this test method to specify the details and protocol of an individual system power measurement prior to the beginning of a measurement.  
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4.1 The design of a photovoltaic module or system intended to provide safe conversion of the sun's radiant energy into useful electricity must take into consideration the possibility of partial shadowing of the module(s) during operation. This test method describes a procedure for verifying that the design and construction of the module provides adequate protection against the potential harmful effects of hot spots during normal installation and use.  
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5.1 Photovoltaic modules are electrical dc sources. dc sources have unique considerations with regards to arc formation and interruption, as once formed, the arc is not automatically interrupted by an alternating current. Solar modules are energized whenever modules in the string are illuminated by sunlight, or during fault conditions.  
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4.1 The design of a photovoltaic module or system intended to provide safe conversion of the sun's radiant energy into useful electricity must take into consideration the possibility of hazard should the user come into contact with the electrical potential of the module or system. In addition, the insulation system provides a barrier to electrochemical corrosion, and insulation flaws can result in increased corrosion and reliability problems. These test methods describe procedures for verifying that the design and construction of the module provides adequate electrical isolation through normal installation and use. At no location on the module should the PV-generated electrical potential be accessible, with the obvious exception of the output leads. This isolation is necessary to provide for safe and reliable installation, use, and service of the photovoltaic system.  
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4.3 Insulation flaws in a module may only become detectable after the module has been wet for a certain period of time. For this reason, these procedures specify a minimum time a module must be immersed prior to the insulation integrity measurements.  
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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.  
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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 E744-07(2022)(Practice)
Standard Practice for Evaluating Solar Absorptive Materials for Thermal Applications

SIGNIFICANCE AND USE
4.1 The methods in this practice are intended to aid in the assessment of long-term performance by comparative testing of absorptive materials. The results of the methods, however, have not been shown to correlate to actual in-service performance.  
4.2 The testing methodology in this practice provides two testing methods, in accordance with Fig. 1.
FIG. 1 Outline of Test Method Options  
4.2.1 Method A, which aims at decreasing the time required for evaluation, uses a series of individual tests to simulate various exposure conditions.  
4.2.2 Method B utilizes a single test of actual outdoor exposure under conditions simulating thermal stagnation.  
4.2.3 Equivalency of the two methods has not yet been established.
SCOPE
1.1 This practice covers a testing methodology for evaluating absorptive materials used in flat plate or concentrating collectors, with concentrating ratios not to exceed five, for solar thermal applications. This practice is not intended to be used for the evaluation of absorptive surfaces that are (1) used in direct contact with, or suspended in, a heat-transfer liquid, (that is, trickle collectors, direct absorption fluids, etc.); (2) used in evacuated collectors; or (3) used in collectors without cover plate(s).  
1.2 Test methods included in this practice are property measurement tests and aging tests. Property measurement tests provide for the determination of various properties of absorptive materials, for example, absorptance, emittance, and appearance. Aging tests provide for exposure of absorptive materials to environments that may induce changes in the properties of test specimens. Measuring properties before and after an aging test provides a means of determining the effect of the exposure.  
1.3 The assumption is made that solar radiation, elevated temperature, temperature cycles, and moisture are the primary factors that cause degradation of absorptive materials. Aging tests are described for exposure of specimens to these factors.  
Note 1: For some geographic locations, other factors, such as salt spray and dust erosion, may be important. They are not evaluated by this practice.  
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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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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