1、March 2016 English price group 10No part of this translation may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).ICS 83.080.01!%LsL“2418041www.din.deDI
2、N EN 16795Plastics Method for estimating heat build up of flat surfaces by simulated solar radiation;English version EN 16795:2015,English translation of DIN EN 16795:2016-03Kunststoffe Verfahren mit simulierter Sonnenstrahlung zur Bewertung der Aufheizung auf ebenen Oberflchen;Englische Fassung EN
3、16795:2015,Englische bersetzung von DIN EN 16795:2016-03Plastiques Mthode destimation de lchauffement de surfaces planes par rayonnement solaire simul;Version anglaise EN 16795:2015,Traduction anglaise de DIN EN 16795:2016-03www.beuth.deDocument comprises 14 pagesDTranslation by DIN-Sprachendienst.I
4、n case of doubt, the German-language original shall be considered authoritative.02.16 DIN EN 16795:2016-03 2 A comma is used as the decimal marker. National foreword This document (EN 16795:2015) has been prepared by Technical Committee CEN/TC 249 “Plastics” (Secretariat: NBN, Belgium). The responsi
5、ble German body involved in its preparation was DIN-Normenausschuss Kunststoffe (DIN Standards Committee Plastics), Working Committee NA 054-01-04 AA Verhalten gegen Umgebungseinflsse. The European Standard referred to in this document has been published as a DIN EN ISO Standard with the same number
6、. There is no DIN Standard available which corresponds to the International Standard referred to. EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 16795 December 2015 ICS 83.080.01 English Version Plastics - Method for estimating heat build up of flat surfaces by simulated solar radiation Plasti
7、ques - Mthode destimation de lchauffement de surfaces planes par rayonnement solaire simul Kunststoffe - Verfahren mit simulierter Sonnenstrahlung zur Bewertung der Aufheizung auf ebenen Oberflchen This European Standard was approved by CEN on 7 November 2015. CEN members are bound to comply with th
8、e CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Managemen
9、t Centre or to any CEN member. This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same status
10、as the official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, N
11、etherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey andUnited Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2015 CEN All
12、rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 16795:2015 EEN 16795:2015 (E) 2 Contents Page European foreword . 3 Introduction 4 1 Scope 5 2 Normative references 5 3 Terms and definitions . 5 4 Abbreviations . 5 5 Principle . 5 6 Apparat
13、us . 6 6.1 General 6 6.2 Test chamber 6 6.3 Laboratory radiation source . 6 6.4 Radiometer 7 6.5 Test chamber temperature and relative humidity . 7 6.6 Surface temperature measurement device . 7 6.7 Black and white standard thermometer 8 6.8 Defined airflow directed across the sample 9 6.9 Specimen
14、holders 9 7 Test specimens . 9 7.1 Form, shape and preparation . 9 7.2 Number of test specimens 9 8 Exposure conditions . 9 8.1 Radiation 9 8.2 Black and white standard thermometer 9 8.3 Chamber air temperature . 10 8.4 Relative humidity of chamber air. 10 8.5 Wind speed . 10 8.6 Sets of exposure co
15、nditions 10 9 Procedure 10 9.1 General . 10 9.2 Mounting the test specimens . 10 9.3 Exposure 10 9.4 Measurement of the surface temperature 11 10 Test report 11 Bibliography . 12 DIN EN 16795:2016-03 EN 16795:2015 (E) 3 European foreword This document (EN 16795:2015) has been prepared by Technical C
16、ommittee CEN/TC 249 “Plastics”, the secretariat of which is held by NBN. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by June 2016 and conflicting national standards shall be withdrawn at the late
17、st by June 2016. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. According to the CEN-CENELEC Internal Regulations, the national stand
18、ards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Lu
19、xembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. DIN EN 16795:2016-03 EN 16795:2015 (E) 4 Introduction Solar radiation causes the temperature of irradiated surfaces to rise substantially above the temperat
20、ure of the surrounding air. The resulting surface temperature depends on the climatic parameters at the location in question, the spectral absorption of the surface, the geometric dimensions and on the specific structure of the object. Generally, the darker the colour, the more the suns energy is ab
21、sorbed and the higher is the heat build-up. The performance characteristics of most of the materials are also defined by the in service temperature. Such materials can be window profiles or other polymeric carrier materials. The micro climate at house walls is also essential defined by the absorbed
22、solar radiation (depending on the material properties). The same applies for interior room and automobile temperatures. The examples reveal the significance of the knowledge of the temperature of sun irradiated surfaces. If the temperature magnitude is estimated to be critical, provisions can be tak
23、en to optimize the in-service micro climate, e.g. reduction of the in-service temperature by improvement of the spectral reflection characteristics or appropriate change in design and improving the air conditioning. DIN EN 16795:2016-03 EN 16795:2015 (E) 5 1 Scope This European Standard specifies a
24、method for estimating the temperature increase of a flat polymer surface, due to its solar radiant energy absorption, compared to the ambient temperature. For that purpose, a specimen and black and white reference plates are exposed to simulated solar radiation under specified conditions (simulated
25、solar radiation, ambient air temperature, convective flow). For opaque specimens, a thermally sensitive electrical element at the backside or a pyrometer is used to measure the surface temperature. For translucent specimens, a pyrometer is used to measure surface temperature. NOTE Some specific poly
26、meric materials are translucent (transparent) and might have a transmittance window in a wavelength range where the used pyrometer is sensitive (e.g. polyethylene). The surface temperature of these materials cannot be measured with the contact and the contactless method. 2 Normative references The f
27、ollowing documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN ISO 4892-
28、1, Plastics - Methods of exposure to laboratory light sources - Part 1: General guidance (ISO 4892-1) ISO 9370, Plastics - Instrumental determination of radiant exposure in weathering tests - General guidance and basic test method 3 Terms and definitions For the purposes of this document, the terms
29、and definitions given in ISO 9370 apply. 4 Abbreviations BST black-standard thermometer CHT chamber air temperature RTD resistance temperature detector WST white-standard thermometer 5 Principle 5.1 A xenon or metal halide arc lamp, fitted with filters, is used to simulate the spectral irradiance of
30、 global solar radiation. 5.2 Specimens are exposed to various levels of simulated global solar radiation, heat, and relative humidity and air flow under controlled environmental conditions, including: a) the irradiance level; b) the air flow directed over the test specimen; c) the ambient air temper
31、ature during the exposure to simulated global solar radiation; DIN EN 16795:2016-03 EN 16795:2015 (E) 6 d) the relative humidity in the chamber during the exposure to simulated global solar radiation. 5.3 The procedure may include measurements of the global irradiance in the plane of the specimens.
32、5.4 The procedure includes measurements of the surface temperature in the plane of the specimens. 5.5 It is recommended to expose simultaneously with the test specimens a black standard (BST) and white standard (WST) thermometer as specified in EN ISO 4892-1 to provide a standard for comparative pur
33、poses. 5.6 Comparison of results obtained from specimens exposed in different apparatus should not be made unless an appropriate statistical relationship has been established between the apparatuses for the particular material exposed. 6 Apparatus 6.1 General The equipment comprises a test chamber,
34、an ozone-free radiation source which generates UV, visible, and infrared radiation similar to solar radiation. A contactless surface temperature device (pyrometer) or contact temperature measuring systems may be part of the device. 6.2 Test chamber The design of the test chamber may vary, but it sha
35、ll be constructed from inert material and shall be equipped with a blower which generates a defined airflow to be directed across the specimens. In addition to the controlled lamp wattage, the test chamber shall provide for control of ambient temperature. For exposures that require control of humidi
36、ty, the test chamber shall include humidity-control facilities that meet the requirements of EN ISO 4892-1. NOTE 1 If the lamp system (one or more lamps) is centrally positioned in the chamber, the effect of any eccentricity of the lamp(s) on the uniformity of exposure can be reduced by using a rota
37、ting frame carrying the specimens or by repositioning or rotating the lamps. NOTE 2 The required irradiance level can be adjusted by means of the lamp wattage. In this case, the lamp wattage is controlled not the irradiance. 6.3 Laboratory radiation source 6.3.1 General The radiation source shall co
38、mprise one or more xenon-arc or metal halide radiation sources which emit radiation from below 270 nm in the ultraviolet through the visible spectrum and into the infrared. In order to simulate global solar radiation, filters shall be used to remove short-wavelength UV radiation (800 nm) may be used
39、 to prevent unrealistic heating of the test specimens. 6.3.2 Spectral irradiance of xenon and metal halide arc lamps with global solar radiation filters Table 1 specifies the minimum and maximum levels of the relative spectral irradiance, in the visible and infrared wavelength range. Filters are a u
40、seful tool to achieve these values. In order to simulate global solar radiation, filters shall be used to remove short-wavelength UV radiation (800 nm) may be used to prevent unrealistic heating of the test specimens. DIN EN 16795:2016-03 EN 16795:2015 (E) 7 NOTE Solar spectral irradiance for a numb
41、er of different atmospheric conditions is described in CIE Publication No. 85 1. The benchmark global solar irradiance used in this standard is that defined in Table 4 in CIE No. 85:1989. Table 1 Relative spectral irradiance of laboratory radiation sources simulating global solar radiation Spectral
42、passband ( = wavelength in nm) Relative spectral portiona% 290 800 60 9 800 3 000 40 9 aThe minimum and maximum tolerance will not necessarily sum to 100 % because they represent tolerance of the measurement data used. For any individual spectral irradiance, the percentages calculated for the passba
43、nds in this table will sum to 100 %. For any individual simulated global solar radiation, the calculated percentage in each passband shall fall within the minimum and maximum limits given. Contact the manufacturer of the simulated global solar radiation apparatus for specific spectral irradiance dat
44、a. 6.3.3 Irradiance uniformity The irradiance at any position in the area used for specimen exposure shall be at least 80 % of the maximum irradiance. NOTE The surface temperature might vary with the irradiance uniformity on sample level. 6.4 Radiometer The radiometer used shall comply with the requ
45、irements given in ISO 9370. 6.5 Test chamber temperature and relative humidity The chamber temperature sensor shall be located, radiation-shielded, possibly combined with a sensor which measures the relative humidity close to the exhaust air duct. For exact calibration of the chamber temperature and
46、 relative humidity sensor it is necessary to move a calibrated working reference standard and the instrument sensor to about the same position so that a balanced temperature and humidity can be set for the measuring sensors and the ambient air. Calibration takes place as soon as the whole system is
47、in thermal balance. NOTE Typically, the thermal equilibrium is achieved after 30 min up to 1 h. 6.6 Surface temperature measurement device 6.6.1 Pyrometer 6.6.1.1 Minimum requirements for the pyrometer A pyrometer may be used to measure the surface temperature of the test specimen on sample level. T
48、he minimum requirements for the pyrometer are the following: a) temperature range: 20 C to 150 C (traceably calibrated by a black body radiator); b) spectral response: 8 m to 14 m; c) IR detector: e.g. silicon based thermopile; d) uncertainty: 0,6 % (in the considered temperature range); DIN EN 1679
49、5:2016-03 EN 16795:2015 (E) 8 e) spot size (diameter): maximum 30 mm. 6.6.1.2 Calibration of the pyrometer The pyrometer shall be calibrated to a traceable national or international standard. Re-calibration by a qualified national or international calibration laboratory should be done at appropriate intervals (e.g. annually). 6.6.1.3 Emissivity of material The temperature of a given object can only be measured correctly if its exact emissivity () in the wave
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