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ASTM E1171-99

(Test Method)

Standard Test Method for Photovoltaic Modules in Cyclic Temperature and Humidity Environments

Standard Test Method for Photovoltaic Modules in Cyclic Temperature and Humidity Environments

SCOPE
1.1 These test methods provide procedures for stressing photovoltaic modules in simulated temperature and humidity environments. Environmental testing is used to simulate aging of module materials on an accelerated basis.
1.2 Three individual environmental test procedures are defined by these test methods: a thermal cycling procedure, a humidity-freeze cycling procedure, and an extended duration damp heat procedure. Electrical biasing is utilized during the thermal cycling procedure to simulate stresses that are known to occur in field-deployed modules.
1.3 These test methods define mounting methods for modules undergoing environmental testing, and specify parameters that must be recorded and reported.
1.4 These test methods do not establish pass or fail levels. The determination of acceptable or unacceptable results is beyond the scope of these test methods.
1.5 Any of the individual environmental tests may be performed singly, or may be combined into a test sequence with other environmental or non-environmental tests, or both. Certain pre-conditioning tests such as annealing or light soaking may also be necessary or desirable as part of such a sequence. The determination of any such sequencing and pre-conditioning is beyond the scope of this test method.
1.6 These test procedures are limited in duration and therefore the results of these tests cannot be used to determine photovoltaic module lifetimes.
1.7 There is no similar or equivalent ISO standard.
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 and health practices and determine the applicability of regulatory limitations prior to use.

General Information

Status
Historical
Publication Date
09-Jun-2001
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 E1171-01 - Standard Test Method for Photovoltaic Modules in Cyclic Temperature and Humidity Environments
Effective Date
10-Jun-2001
Referred By
ASTM E772-15(2021) - Standard Terminology of Solar Energy Conversion
Effective Date
10-Jun-2001

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ASTM E1171-99 - Standard Test Method for Photovoltaic Modules in Cyclic Temperature and Humidity EnvironmentsASTM E1171-99 - Standard Test Method for Photovoltaic Modules in Cyclic Temperature and Humidity Environments
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ASTM E1171-99 - Standard Test Method for Photovoltaic Modules in Cyclic Temperature and Humidity Environments
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NOTICE: This standard has either been superseded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
Designation: E 1171 – 99 An American National Standard
Standard Test Methods for
Photovoltaic Modules in Cyclic Temperature and Humidity
Environments
This standard is issued under the fixed designation E 1171; 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 E 1462 Test Methods for Insulation Integrity and Ground
Path Continuity of Photovoltaic Modules
1.1 These test methods provide procedures for determining
E 1799 Practice for Visual Inspections of Photovoltaic
the ability of photovoltaic modules to withstand simulated
Modules
temperature and humidity environments. Environmental test-
E 1830M Test Methods for Determining the Mechanical
ing is used to simulate aging of module materials on an
Integrity of Photovoltaic Modules
accelerated basis.
1.2 Three individual environmental test procedures are de-
3. Terminology
fined by these test methods: a thermal cycling procedure, a
3.1 Definitions—definitions of terms used in this standard
humidity-freeze cycling procedure, and an extended duration
may be found in Terminology E 772 and in Terminology
damp heat procedure.
E 1328.
1.3 These test methods define mounting methods for mod-
3.2 Definitions of Terms Specific to This Standard:
ules undergoing environmental testing, and specify parameters
3.2.1 ground fault—a module fault where any portion of the
that must be recorded and reported.
module circuitry between the output terminals becomes elec-
1.4 These test methods do not establish pass or fail levels.
trically connected to the module grounding point.
The determination of acceptable or unacceptable results is
3.2.2 open circuit—a module fault where any portion of the
beyond the scope of these test methods.
module circuitry between the output terminals becomes elec-
1.5 Any of the individual environmental tests may be
trically discontinuous.
performed singly, or may be combined into a test sequence
with other environmental or non-environmental tests, or both.
4. Significance and Use
Certain pre-conditioning tests such as annealing or light
4.1 The useful life of photovoltaic modules may depend on
soaking may also be necessary or desirable as part of such a
their ability to withstand repeated temperature cycling with
sequence. The determination of any such sequencing and
varying amounts of moisture in the air. These test methods
pre-conditioning is beyond the scope of this test method.
provide procedures for simulating the effects of cyclic tem-
1.6 There is no similar or equivalent ISO standard.
perature and humidity environments. An extended duration
1.7 This standard does not purport to address all of the
damp heat procedure is provided to simulate the effects of long
safety concerns, if any, associated with its use. It is the
term exposure to high humidity.
responsibility of the user of this standard to establish appro-
4.2 These test methods describe procedures for mounting
priate safety and health practices and determine the applica-
test modules, conducting the environmental tests, and reporting
bility of regulatory limitations prior to use.
the results.
2. Referenced Documents 4.2.1 Test modules are mounted so that they are electrically
isolated from each other, and in such a manner to allow free air
2.1 ASTM Standards:
2 circulation around the front and back surfaces of the modules.
E 772 Terminology Relating to Solar Energy Conversion
4.3 Data generated using these test methods may be used to
E 1036 Methods of Testing Electrical Performance of Non-
evaluate and compare the effects of simulated environment on
concentrator Terrestrial Photovoltaic Modules and Arrays
2 test specimens. These test methods require determination of
Using Reference Cells
both visible effects and electrical performance effects.
E 1328 Terminology Relating to Photovoltaic Solar Energy
2 4.3.1 Effects on modules may vary from none to significant
Conversion
changes. Some physical changes in the module may be visible
when there are no apparent electrical changes in the module.
This test method is under the jurisdiction of ASTM Committee E-44 on Solar,
Similarly, electrical changes may occur with no visible changes
Geothermal, and Other Alternative Energy Sources and is the direct responsibility of
in the module.
Subcommittee E44.09 on Photovoltaic Electrical Power Systems.
Current edition approved Oct. 10, 1999. Published November 1999. Originally
4.3.2 All conditions of measurement, effects of cycling, and
published as E 1171–87. Last previous edition E 1171–97.
any deviations from this test method must be described in the
Annual Book of ASTM Standards, Vol 12.02.
Copyright © ASTM, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959, United States.
E 1171
report so that an assessment of their significance can be made. temperature cycling, humidity-freeze cycling, and damp heat
4.4 If these test methods are performed as part of a procedures may be performed individually, the requirements of
combined sequence with other environmental or non- any test sequence (see 1.5 and 4.4) may determine the order in
environmental tests, the results of the final electrical tests (7.2) which the environmental tests are performed, and also may
and visual inspection (7.3) determined at the end of one test impose restrictions on which test modules are to be subjected
may be used as the initial electrical tests and visual inspection to individual procedures. The sequencing may also specify
for the next test; duplication of these tests is not necessary when modules undergo electrical testing (see 6.2) and visual
unless so specified. inspections (see 6.3).
6.1.1 A typical combined thermal and humidity-freeze cy-
5. Apparatus
cling sequence is illustrated in Fig. 1.
5.1 In addition to the apparatus required for Test Methods
6.2 Electrical Tests—Perform the following electrical tests
E 1036 and E 1462 the following apparatus is required.
before and after each of the test procedures.
5.2 Environmental Chamber(s)—A chamber or chambers in
6.2.1 Electrical Performance—Measure and record the
which modules are mounted during the environmental tests.
electrical performance of each module. A suitable method for
5.2.1 Air temperature throughout the working volume shall
nonconcentrator modules is Test Methods E 1036.
be within 62°C of that specified.
6.2.2 Ground Path Continuity—Test any module with a
5.2.2 Relative humidity shall be controlled within 65% of
grounding terminal identified by the module manufacturer to
that specified. For temperatures below 80°C, relative humidity
determine the maximum resistance between the grounding
control is not required.
terminal or lead and any accessible conductive part using 7.3 of
5.2.3 Provisions for monitoring and recording the chamber Test Methods E 1462.
temperature and relative humidity throughout the environmen-
6.2.3 Insulation Integrity—Subject each module to a test of
tal testing shall be provided. the electrical isolation capability according to 7.1 and 7.2 of
5.3 Tempe
...

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1.1 This practice provides procedures for determining the expected capacity of a specific photovoltaic system in a specific geographical location that is in operation under natural sunlight during a specified period of time. The expected capacity is intended for comparison with the measured capacity determined by Test Method E2848.  
1.2 This practice is intended for use with Test Method E2848 as a procedure to select appropriate reporting conditions (RC), including solar irradiance in the plane of the modules, ambient temperature, and wind speed needed for the photovoltaic system capacity measurement.  
1.3 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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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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1.1 This test method provides measurement and analysis procedures for determining the capacity of a specific photovoltaic system built in a particular place and in operation under natural sunlight.  
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1.4 In this test method, photovoltaic system power is reported with respect to a set of reporting conditions (RC) including solar irradiance in the plane of the modules, ambient temperature, and wind speed (see Section 6). Measurements under a variety of reporting conditions are allowed to facilitate testing and comparison of results.  
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4.1 Environmental stress tests, such as those listed in 1.2, are normally used to evaluate module designs prior to production or purchase. These test methods rely on performing electrical tests and visual inspections of modules before and after stress testing to determine the effects of the exposures.  
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SCOPE
1.1 This practice covers procedures and criteria for visual inspections of photovoltaic modules.  
1.2 Visual inspections of photovoltaic modules are normally performed before and after modules have been subjected to environmental, electrical, or mechanical stress testing, such as thermal cycling, humidity-freeze cycling, damp heat exposure, ultraviolet exposure, mechanical loading, hail impact testing, outdoor exposure, or other stress testing that may be part of the photovoltaic module testing sequence.  
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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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1.3 This guide is intended for systems which contain photovoltaic modules and panels as dc source circuits, although the recommended practices may also apply to systems utilizing ac modules.  
1.4 This guide does not cover fire suppression in the event of a fire involving a photovoltaic module or system.  
1.5 This guide does not cover fire emanating from other sources.  
1.6 This guide does not cover mechanical, structural, electrical, or other considerations key to photovoltaic module and system design and installation.  
1.7 This guide does not cover disposal of modules damaged by a fire, or other material hazards related to such modules.  
1.8 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.9 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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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.  
4.2 This test method describes a procedure for determining the ability of the module to provide protection from electrical hazards. Its primary use is to find insulation flaws that could be dangerous to persons who may come into contact with the module, especially when modules are wet. For example, these flaws could be small holes in the encapsulation that allow hazardous voltages to be accessible on the outside surface of a module after a period of high humidity.  
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.  
4.4 Electrical junction boxes attached to modules are often designed to allow liquid water, accumulated from condensed water vapor, to drain. Such drain paths are usually designed to permit water to exit, but not to allow impinging water from rain or water sprinklers to enter. It is important that all surfaces of junction boxes be thoroughly wetted by spraying during the tests to enable t...
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1.1 These test methods provide procedures to determine the insulation resistance of a photovoltaic (PV) module, i.e. the electrical resistance between the module's internal electrical components and its exposed, electrically conductive, non-current carrying parts and surfaces.  
1.2 The insulation integrity procedures are a combination of wet insulation resistance and wet dielectric voltage withstand test procedures.  
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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.  
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1.6.1 Part of an assembled collector (Type 1 specimen), or  
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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 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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