1、Designation: G183 05 (Reapproved 2010)G183 15Standard Practice forField Use of Pyranometers, Pyrheliometers and UVRadiometers1This standard is issued under the fixed designation G183; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision,
2、 the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice describes deployment conditions, maintenance requirements, verification procedures and cali
3、brationfrequencies for use of pyranometers, pyrheliometers and UV radiometers in outdoor testing environments. This practice alsodiscusses the conditions that dictate the level of accuracy required for instruments of different classes.types.1.2 While both pyranometers and UV radiometers may be emplo
4、yed indoors to measure light radiation sources, themeasurement of ultraviolet and light radiation in accelerated weathering enclosures using manufactured light sources generallyrequires specialized radiometric instruments. Use of radiometric instrumentation to measure laboratory light sources is cov
5、ered inISO 9370.NOTE 1An ASTM standard that is similar to ISO 9370 is under development and deals with the instrumental determination of irradiance and radiantexposure in weathering tests.1.3 The characterization of radiometers is outside the scope of the activities required of users of radiometers,
6、 as contemplatedby this standard.2. Referenced Documents2.1 ASTM Standards:2E772 Terminology of Solar Energy ConversionG7 Practice for Atmospheric Environmental Exposure Testing of Nonmetallic MaterialsG24 Practice for Conducting Exposures to Daylight Filtered Through GlassG90 Practice for Performin
7、g Accelerated Outdoor Weathering of Nonmetallic Materials Using Concentrated Natural SunlightG113 Terminology Relating to Natural and Artificial Weathering Tests of Nonmetallic Materials2.2 ISO Standards:3ISO 877 PlasticsMethods of Exposure to Direct Weathering, Indirect Weathering Using Glass-Filte
8、red Daylight and IndirectWeathering by Daylight Using Fresnel MirrorsISO 9060 Solar EnergySpecification and Classification of Instruments for Measuring Hemispherical Solar and Direct SolarRadiationISO 9370 PlasticsInstrumental Determination of Radiant Exposure in Weathering TestsGeneral GuidanceISO
9、TR 9901 Solar EnergyField PyranometersRecommended Practice for Use2.3 OtherWMO Reference:4World Meteorological Organization (WMO), 1983 “Measurement of Radiation,” Guide to Meteorological Instruments andMethods of Observation, fifthseventh ed., WMO-No. 8, Geneva3. Terminology3.1 DefinitionsThe defin
10、itions given in Terminologies E772 and G113 are applicable to this practice.1 This practice is under the jurisdiction of ASTM Committee G03 on Weathering and Durability and is the direct responsibility of Subcommittee G03.09 on Radiometry.Current edition approved Dec. 1, 2010Feb. 1, 2015. Published
11、December 2010February 2015. Originally approved in 2005. Last previous edition approved in 20052010as G183 05.G183 05(2010). DOI: 10.1520/G0183-05R10.10.1520/G0183-15.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual B
12、ook of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.3 Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http:/www.ansi.org.International Organization forStandardization (ISO), 1, ch. de la
13、 Voie-Creuse, CP 56, CH-1211 Geneva 20, Switzerland, http:/www.iso.org.4 Available from World Meterological Organization, 7 bis, avenue de la Paix, CP. 2300, CH-1211 Geneva 2, Switzerland, http:/www.wmo.int.This document is not an ASTM standard and is intended only to provide the user of an ASTM sta
14、ndard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by AS
15、TM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States14. Radiometer Selection4.1 Criteria for the Selection of Radiometers:4.1.1 There are several criteria that need to be considered for selectio
16、n of the radiometer that will be used:4.1.1.1 Function specific criteria, such as whether a pyranometer, pyrheliometer or UV radiometer is required,4.1.1.2 Task specific criteria, such as the accuracy requirements for the selected incident angle and temperature ranges, andmaximum response time,4.1.1
17、.3 Operational criteria, such as dimensions, weight, stability and maintenance, and4.1.1.4 Economic criteria, such as when networks have to be equipped, or whether the instrument is being acquired for internalreference purposes, or for research purposes, etc.4.2 Selection Related to Radiometer Type:
18、4.2.1 Pyranometers, which measure global solar irradiance in the 300 to 2500 nm wavelength region, are required to assess thehemispherical solar irradiance on surfaces of test specimens mounted on weathering test racks that are used by the outdoorweathering exposure community. Typically, pyranometer
19、s are required to measure the exposure levels specified in the applicableASTM and/or ISO outdoor weathering standards such as those described in Practices G7, G24, G90, and ISO 877.4.2.2 Pyrheliometers, which measure direct (or, beam) solar irradiance in the 300 to 2500 nm wavelength region, are req
20、uiredto assess the solar irradiance reflected onto the target board by the mirrors of Fresnel Reflecting Concentrators used in outdooraccelerated tests specified by ASTM and ISO Standards described in Practice G90 and ISO 877.4.2.3 Ultraviolet radiometers are either broad band or narrow band instrum
21、ents covering defined wavelength regions of the solarultraviolet spectrum.4.2.3.1 Broad-band UV radiometers usually are designed to measure either UV-A, UV-B or some component of both UV-AandUV-B radiation.NOTE 2Certain UV radiometers that are designated as total ultraviolet radiometers are advertis
22、ed to measure over the total wavelength range fromthe so called UV cutoff at approximately 300 nm to 385 or 400 nm, but in fact measure mostly UV-A radiation by virtue of their very low responsivityto wavelengths below 315 nm.4.2.3.2 Narrow-band UV radiometers are essentially constructed using inter
23、ference filters that isolate narrow bands of radiationhaving FWHM values of 20 nm, or less; their center wavelengths (CW) may reside anywhere in the UV spectrum from 280 to400 nm wavelengthdepending on the application for which they are intended.NOTE 3While the World Meteorological Organization (WMO
24、) and the International Standards Organization (ISO) have established requirements forSecondary Standard and First-, Second- and Third-class High, Good, and Moderate Quality pyranometers and pyrheliometers, specifications and requiredoperational characteristics of different classes of ultraviolet ra
25、diometers have not been addressed by either organization.NOTE 4First-class High Quality instruments are not necessary for all applications.4.3 Selection Related to Measuring Specifications:4.3.1 As a first step, all possible ranges of measuring parameters such as temperature, irradiance levels, angl
26、es of incidence, tiltangles, and station latitude, must be compiled.4.3.2 Next, documentation must be compiled of available information about the technical characteristics, and the technical andphysical specifications of the relevant radiometers given by:4.3.2.1 The WMO and ISO classification of pyr
27、anometers given in the WMO Guide, and in ISO 9060 and ISO 9370 (whichtogether define the specifications to be met by different categories of pyranometers and pyrheliometers),4.3.2.2 The data specification sheets obtained from the manufacturer, and4.3.2.3 Preferably, data on the technical characteris
28、tics and performance obtained from independent sources such as independenttesting laboratories, research institutes and government laboratories.4.3.3 If the accuracy of the highest category of instrument is insufficient for the application contemplated, the followingrecommendations are given:4.3.3.1
29、 Hemispherical solar radiation may be measured by the simultaneous deployment of a pyrheliometer and a continuouslyshaded secondary standard pyranometer to achieve accuracies that are greater than can be achieved by a secondary standardpyranometer alone,4.3.3.2 Direct (beam) solar radiation may be m
30、easured using an absolute cavity pyrheliometer employing electrical substitutionof thermally absorbed radiation to achieve accuracies that are greater than can be achieved by a First-class pyrheliometer, and4.3.3.3 Specific ultraviolet wavelength bands may be determined by integration of the selecte
31、d wavelength bands using ascanning spectroradiometer possessing good slit function and narrow band pass characteristics to achieve accuracies that aregreater than the most accurate narrow or broad band ultraviolet radiometers currently commercially available.5. Practice for UseGeneral5.1 Installatio
32、n of Radiometers:5.1.1 When performing measurements in support of testing, the test object and the field radiometer shall be equally exposed withrespect to field of view, ground radiation and any stray light that may be present.This means that the test surface and the radiometershall receive the sam
33、e irradiance.G183 1525.1.2 When used to determine the irradiance accumulated on solar concentrating devices such as the Fresnel reflectingconcentrators used in the practice of Practice G90, and other types of solar concentrators, it is essential that the collection systemof the solar concentrators,
34、such as the flat mirrors used in the practice of Practice G90, do not receive direct irradiance that isunavailable to the optical system that connotes the pyrheliometer required.5.1.3 The need for easy access to the radiometer for maintenance operations shall be considered in selecting the installat
35、ion site,mount, etc.5.2 Electrical Installation:5.2.1 The electrical cable employed shall be secured firmly to the mounting stand to minimize the possibility of breakage orintermittent disconnection in severe weather.5.2.2 Wherever possible, the electrical cable shall be protected and buried undergr
36、oundparticularly when recording devices,controllers, or converters are located at a distance. Use of shielded cable is highly recommended. The cable, recorder and otherelectronic devices, shall be connected by a very low resistance conductor to a common ground.5.2.3 Contact the manufacturer of the r
37、adiometer being installed to establish the maximum allowable cable length permissiblefor the instruments impedance so as to preclude significant signal loss (see 5.4.5.2 for additional requirements).5.2.4 When hard wiring electrical connections, all exposed junctions shall be weatherproofed and prot
38、ected from physicaldamage.5.2.5 Establish and identify the polarity of all relevant connections prior to connecting to the recording device, converters, orcontrollers. Make all connections in accordance with the manufacturers instructions.5.3 Required Maintenance Activities:5.3.1 Inspection:5.3.1.1
39、Whenever possible, inspect radiometers employed in continuous operation at least once each day. Inspection andmaintenance activities of specific attributes described in the following sections should be carried out daily, monthly and yearly asindicated.NOTE 5It should be noted that the quality of dat
40、a obtained using total solar and solar ultraviolet radiometers depends strongly on the amount ofpersonal attention given during the observation program.5.3.2 Daily Routine Inspection and Maintenance:5.3.2.1 The exterior glass domes and/or diffusers or windows, shall be inspected daily and cleaned at
41、 least once each week ormore often whenever dust or other deposits are visible. Cleaning shall occur by spraying with deionized water and wiping dry withnon-abrasive and lint-free cloth or tissue. It is recommended that this inspection and possible cleaning be performed early eachday.5.3.2.2 If froz
42、en snow, glazed frost, hoar frost or rime is present, remove the deposit very gently, initially with the sparing useof a de-icing fluid, fluid or a warm lint-free cloth, appropriate for the type of glass dome, window, or diffuser, after which thewindow glass dome, window, or diffuser shall be wiped
43、clean and dry.5.3.2.3 After heavy dew, rain, sleet, snow or frost buildup, check to determine if condensation is present inside the dome, oron the receptor or diffuser surface. If condensation is discovered inside the dome, on the receptor or diffuser surface of domedradiometers, the instruments man
44、ufacturer shall be contacted to determine a course of action.NOTE 6The user may attempt to “dry out” the radiometer by elevating its temperature, either in natural sunlight or in the laboratory, to 50C. If thecondensation is eliminated, the radiometers calibration constant shall be checked prior to
45、being returned to service.5.3.2.4 When hard-to-remove deposits of air pollution or local contamination is observed on a radiometers exterior window,first apply deionized or distilled water on the surface. If the use of a detergent solution is indicated, a prepare a 2 % solution ofa mild dish washing
46、 detergent and gently apply to the surface. Use a soft, lint-free muslin cloth to gently rub the surface if required.In either case, thoroughly rinse the surface with deionized or distilled water, after which it the window shall be wiped clean anddry. Water spots should not be evident on the surface
47、. However, care should be exercised to avoid scratching the surface.NOTE 7The user may use optics cleaning compressed air to blow away all remaining water droplets from the surface after cleaning. Use small,controlled puffs of air, being careful not to discharge any propellant that may leave a resid
48、ue on the window. Check for any streaking or lint left by thecleaning materials and repeat if necessary.5.3.2.5 When used, check the operational state of the ventilator or air blower at least weekly and note any unusual noise forsubsequent attention. Further, check the condition of ventillation unit
49、 filters and clean or replace as necessary.5.3.2.6 Perform a cursory check of the output data on at least a weekly basis to determine if data being recorded are plausiblein relation to the conditions being experienced.5.3.3 Monthly Routine Inspection and Maintenance:5.3.3.1 Examine the color-indicating desiccant for all instruments where the silica gel container is accessible. If moisture isindicated, replace the desiccant.NOTE 8If desiccant is consumed rapidly, the cause might be a defective seal of the instruments window, a defective electrical conn
