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ASTM E2047-05

(Test Method)

Standard Test Method for Wet Insulation Integrity Testing of Photovoltaic Arrays

Standard Test Method for Wet Insulation Integrity Testing of Photovoltaic Arrays

SCOPE
1.1 This test method covers a procedure to determine the insulation resistance of a photovoltaic (PV) array (or its component strings), that is, the electrical resistance between the array's internal electrical components and is exposed, electrically conductive, non-current carrying parts and surfaces of the array.
1.2 This test method does not establish pass or fail levels. The determination of acceptable or unacceptable results is beyond the scope of this test method.
1.3 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
31-Mar-2005
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 E2047-99 - Standard Test Method for Wet Insulation Integrity Testing of Photovoltaic Arrays
Effective Date
01-Apr-2005
Replaced By
ASTM E2047-10 - Standard Test Method for Wet Insulation Integrity Testing of Photovoltaic Arrays
Effective Date
01-Jun-2010
Referred By
ASTM E3010-15(2019)e1 - Standard Practice for Installation, Commissioning, Operation, and Maintenance Process (ICOMP) of Photovoltaic Arrays
Effective Date
01-Apr-2005

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ASTM E2047-05 - Standard Test Method for Wet Insulation Integrity Testing of Photovoltaic ArraysASTM E2047-05 - Standard Test Method for Wet Insulation Integrity Testing of Photovoltaic Arrays
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ASTM E2047-05 - Standard Test Method for Wet Insulation Integrity Testing of Photovoltaic Arrays
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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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:E2047–05
Standard Test Method for
1
Wet Insulation Integrity Testing of Photovoltaic Arrays
This standard is issued under the fixed designation E2047; 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 3.2.3 photovoltaic circuit—the active electrical circuit that
conducts the photovoltaic generated power.
1.1 This test method covers a procedure to determine the
insulation resistance of a photovoltaic (PV) array (or its
4. Summary of Test Method
component strings), that is, the electrical resistance between
4.1 A procedure is provided for testing the electrical isola-
the array’s internal electrical components and is exposed,
tion between the array’s internal electrical components and its
electrically conductive, non-current carrying parts and surfaces
exposed, electrically conductive, non-current carrying parts
of the array.
and surfaces of the array.
1.2 This test method does not establish pass or fail levels.
4.2 The procedure offers two ways to connect the array
The determination of acceptable or unacceptable results is
during the test, either open-circuited or short-circuited. Each
beyond the scope of this test method.
option has advantages and disadvantages (see 5.5).
1.3 This standard does not purport to address all of the
4.3 Awetting solution is applied to the array, then a voltage
safety concerns, if any, associated with its use. It is the
is applied between the PV circuit and the exposed, electrically
responsibility of the user of this standard to establish appro-
conductive, non-current carrying parts and surfaces of the
priate safety and health practices and determine the applica-
array, while monitoring the current or resistance, to find
bility of regulatory limitations prior to use.
localized regions where the insulation resistance is signifi-
2. Referenced Documents cantly reduced by the wetting solution. The array is then
2
inspected for evidence of possible arcing.
2.1 ASTM Standards:
E772 Terminology Relating to Solar Energy Conversion
5. Significance and Use
E1328 Terminology Relating to Photovoltaic Solar Energy
5.1 The design of a PV module or system intended to
Conversion
provide safe conversion of the sun’s radiant energy into useful
E1462 Test Methods for Insulation Integrity and Ground
electricitymusttakeintoconsiderationthepossibilityofhazard
Path Continuity of Photovoltaic Modules
should the user come into contact with the electrical potential
3. Terminology of the array. In addition, the insulation system provides a
barrier to electrochemical corrosion, and insulation flaws can
3.1 Definitions—Definitions of terms used in this test
result in increased corrosion and reliability problems. This test
method may be found in Terminologies E772 and E1328.
method describes a procedure for verifying that the design and
3.2 Definitions of Terms Specific to This Standard:
construction of the array provides adequate electrical isolation
3.2.1 insulation resistance, n—the electrical resistance of a
throughnormalinstallationanduse.Atnolocationonthearray
photovoltaic array’s insulation, measured between the photo-
should the PV-generated electrical potential be accessible, with
voltaic circuit and exposed, electrically conductive non-
the obvious exception of the output leads. The isolation is
current-carrying parts and surfaces of the array.
necessary to provide for safe and reliable installation, use, and
3.2.2 metal oxide varistor MOV, n—a surge protection
service of the PV system.
device.
5.2 This test method describes a procedure for determining
the ability of the array to provide protection from electrical
1
This test method is under the jurisdiction of ASTM Committee E44 on Solar, hazards. Its primary use is to find insulation flaws that could be
Geothermal and Other Alternative Energy Sources , and is the direct responsibility
dangerous to persons who may come into contact with the
of Subcommittee E44.09 on Photovoltaic Electrical Power Conversion.
array. Corrective action taken to address such flaws is beyond
Current edition approved April 1, 2005. Published May 2005. Originally
the scope of this test method.
approved in 1999. Last previous edition approved in 1999 as E2047–99. DOI:
10.1520/E2047-05.
5.3 This procedure may be specified as part of a series of
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
acceptance tests involving performance measurements and
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
demonstration of functional requirements. Large arrays can be
Standards volume information, refer to the standard
...

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FIG. 1 Hot Spot Effect  
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FIG. 2 Bypass Diode Effect  
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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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1.3.2 Testing of individual photovoltaic modules or systems for comparison to other photovoltaic modules or systems, and  
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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  
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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).  
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SIGNIFICANCE AND USE
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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.  
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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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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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