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IS 12933-3: Solar Flat Plate Collector, Part 3: Measuring Instruments PDF

10 Pages·2003·0.99 MB·English
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इंटरनेट मानक Disclosure to Promote the Right To Information Whereas the Parliament of India has set out to provide a practical regime of right to information for citizens to secure access to information under the control of public authorities, in order to promote transparency and accountability in the working of every public authority, and whereas the attached publication of the Bureau of Indian Standards is of particular interest to the public, particularly disadvantaged communities and those engaged in the pursuit of education and knowledge, the attached public safety standard is made available to promote the timely dissemination of this information in an accurate manner to the public. “जान1 का अ+धकार, जी1 का अ+धकार” “प0रा1 को छोड न’ 5 तरफ” Mazdoor Kisan Shakti Sangathan Jawaharlal Nehru “The Right to Information, The Right to Live” “Step Out From the Old to the New” IS 12933-3 (2003): Solar Flat Plate Collector, Part 3: Measuring Instruments [MED 4: Non-Conventional Energy Sources] “!ान $ एक न’ भारत का +नम-ण” Satyanarayan Gangaram Pitroda ““IInnvveenntt aa NNeeww IInnddiiaa UUssiinngg KKnnoowwlleeddggee”” “!ान एक ऐसा खजाना > जो कभी च0राया नहB जा सकता हहहहै””ै” Bhartṛhari—Nītiśatakam “Knowledge is such a treasure which cannot be stolen” REAFFIRMED 2003 IS 12933 (Part 3) : 2003 'J-f7'?rf)2/ JWfF1C/? mx"WTIC ~ ~-~ pm-erur ) ( 4E5(YJ! Indian Standard SOLAR FLAT PLATE COLLECTOR-SPECIFICATION PART 3 MEASURING INSTRUMENTS ( First Revision) ICS 27.160 ©BIS2003 BUREAU OF INDIAN STANDARDS MANAK BHAVAN, 9 BAHADUR SHAH ZAFAR MARG NEW DELHI 110002 June 2003 PriceGroup 2 AMENDMENT NO. 1 JUNE 2005 TO IS 12933(PART 3): 2003 SOLAR FLAT PLATE COLLECTOR - SPECIFICATION PART 3 MEASURING INSTRUMENTS ( First Revision ) ( Page I, clause 4.1, second sentence) - Substitute the following for the existing: 'For thermal performance test only, the instrument shall have the following minimum characteristics. which are consistent with or superior to those of a pyranometeraccordingtoIS 8336.' (ME04) ReprographyUnit.illS.NewDelhi, India ·Non-conventionalEnergySources SectionalCommittee,ME 04 FOREWORD This Indian Standard (Part 3) (FirstRevision) was adopted by the Bureau ofIndian Standards, after the draft finalized by the Non-conventional Energy Sources SectionalCommitteehad been approved by the Mechanical EngineeringDivisionCouncil. This standardwas publishedin 1990. Inthis revision attempthas been madeto align the measuring instruments requirementsfor measuringsolarradiation,temperature liquid flow, pressuretime, mass and wind velocitywith those given in ISO 9060-1990 'Solar Energy- Specification and classification of instruments for measuring hemisphericalysolarand directsolar radiation' as faraspossible. In orderto facilitate the reference and use, this standard is one ofa series ofsolar flat plate collector standards. Otherstandardsare as follows: IS No. Title IS 12933 Solarflat plate collectcr-s-Specification: (Part 1):2003 Requirements (secondrevision) (Part2) :2003 Components(secondrevision) (Part5) :2003 Test methods(secondrevision) Part4ofthisstandardwhichcoveredperformancerequirementsandacceptancecriteriaforsolarflat.platecollectors was subsequentlywithdrawnand itscontentsincorporated inPart 1. For the purpose ofdeciding whethera particularrequirementofthis standard is compliedwith, the final value, observed or calculated, expressing the result of a test or analysis, shall be rounded off in accordance with IS2:1960 'Rules for rounding offnumerical values (revised)'. The numberofsignificantplacesretained inthe rounded offvalueshouldbethe same asthat ofthe specifiedvalue inthis standard. IS 12933 (part 3) :2003 Indian Standard SOLAR FLAT PLATE COLLECTOR-SPECIFICATION PART 3 MEASURING INSTRUMENTS ( First Revision) 1 SCOPE 4 MEASUREMENTOF SOLARRADIATION 1.1 This standard (Part 3) specifies the measuring 4.1 A pyranometer shall be used to carry out instruments for solar flat plate collector for water measurementofglobalshortwaveradiationfrom both heating. the sun and the sky. The instrument shall have the following minimum characteristics, which are 1.2 This standarddoes not applyto the following: consistent with or superior to those of a first class a) Collector in whom heat transfer fluid may pyranometer as classified in IS 8336, except where changephase,thatis,thecollectorsdesignedfor noted. normal fluid temperature above 100°C with waterasthe heattransferfluid; 4.1.1 Change ofResponseDueto VariationinAmbient Temperature b) Concentrating collectors, used in a system designed to generate mechanical energy/ The change in the instrument's response due to electricity; variations in ambient temperature shall be less than c) Collectors in which the thermal storageunit is ±1percentduringthe test. an integral part of the collector so that the collection and the storage processes cannot be 4.1.2 Variation inSpectralResponse separated; Pyranometersshallhave aconstantsensitivitytowithin d) Unglazed flat plate collector; ± 2 percent over the spectral range from 0.3 to 2.5 e) Installationormountingofsolarcollectors;and microns.. f) Tracking mechanism of the sun following 4.1.3 Non-linearityofResponse collectorsystem. The responseofthe pyranometerinrespectoflinearity 2 REFERENCES over the range of irradiance during the test shall be The following standards contain provisions, which within±1percent. If it ismore, then the pyranometer through reference in this text, constitute provision of shall be used with acalibration curve inthis respect. this standard. At the timeofpublication,the editions 4.1.4 TimeResponse indicated were valid. All standards are subject to revision, and parties to agreements based on this The time constant ofthe pyranometer, defined as the standard are encouraged to investigatethe possibility time required for the instrument to achieve a reading ofapplying the most recent editions ofthe standards of63.2percent[thatis(I-lie)]ofitsfinal readingafter indicated below: astep change insolarirradiance,shall be lessthan 5s. IS No. Title 4.1.5 Variation ofResponsewithAngleofIncidence 2806 1992 Guide to electrical resistance thermometry(first revision) Ideally, theresponseofthe pyranometerisproportional to the cosine ofthe incident angle ofthe direct solar 3636 1966 Method of test for temperature radiation and is constant at all azimuth angles. The coefficient of precision resistor deviation ofthepyranometer reading for the incident wires angles encountered during the tests shall be less than 8336 1977 Thermoelectric pyranometer ±1percentfrom atrue cosineresponse 12934 1990 Solarenergy- thermalapplications - Vocabulary 4.1.6 Variation ofResponsewith Tilt 3 TERMINOLOGY The variation in response ofthe pyranometer for tiIts ranging from horizontal to the largesttilt encountered For the purpose ofthis standard, the terminologyand duringthe testshall not be greaterthan ±1percent. definitions given in IS 12934 shall apply. IS 12933 (Part3) :2003 4,2 Precautions for Effects of Humidity and that itssensorisco-planerwiththeplaneofthecollector Moisture aperture. Itshall not cast a shadow onto the collector aperture atany time during the test period. The The pyranometer shall be provided with means of pyranometershall bemountedatthe mid-heightofthe preventingaccumulationofmoisturethatmaycondense collector so as to receive the same levels of solar onsurfaceswithinthe instrumentandaffectitsreading. radiationas are received bythe collector. An instrumentwith a desiccatorthat can be inspected is required. The condition ofthe desiccator shall be 5 TEMPERATUREMEASUREMENTS observedpriortoandfollowingeachdailymeasurement 5.1 Temperature measurements shall be made in sequence. accordancewith IS2806 and IS3636. 4.3 PrecautionsforEffectsofTemperatureGradient 5.2 MeasurementoflnletandOutletTemperatures The pyranometer used during the test shall be placed ofthe HeatTransferFluid inatypical test position and allowed to equilibratefor Theaccuracy of the instruments (including their at least 30 min beforedata-takingcommences. associatedreadoutdevices)employedformeasurement 4.4 Calibration ofPyranometer ofinletandoutlettemperaturesoftheheattransferfluid shall be± 0.1DC. For ensuringthat the temperatureis The pyranometershall becalibratedfor solarresponse not driftingwith time, a resolution ofthe temperature within 12months preceding the collector test against signalbetterthan± O.02°e isrequired. other pyranometers whose calibration uncertainty relativetorecognizedmeasurementstandardsisknown. 5.2.1 Mounting ofSensors Any changeofmorethan±1percentoverayearperiod The transducer shall be mounted at no more than shall warrant the use ofmore frequent calibration or 200 mm from thecollectorarea and insulationshall be replacement ofthe instrument. If the instrument is placed both upstream and downstream of the damaged in any significant manner, it shall be transducers. To ensure mixing ofthe fluid at the recalibratedor replaced. positionofthe temperaturemeasurement,abentinthe 4.5 MountingofPyranometerOutdoors pipe work, anorificeor afluid mixingdeviceshall be placed upstream ofthe transducer and the transducer The pyranometer shall be mounted in such a manner probeshall point upstream as shown in Fig. 1. TEMPERATURE TRANSDUCER T e ....----.....;- / LJ TEMPERATUR~~'j'!·:'·C!( PIPEWORK BEND TRANSDUCER Ti OR MIXING DEVICE SOLAR COLLECTOR PIPEWORK BEND OR MIXING DEVICE All dimensions inmillimetres. FIG. 1 RECOMMENDED TRANSDUCER POSITIONS FOR MEASURING THE HEAT TRANSFER FLUID IN LETAND OUTLET TEMPERATURES 2 IS 12933 (Part3) :2003 5.2.2 Calibration ofSensors arithmetic average of sample values or by a time integration overthe test period. The sensors used for measuring inlet and outlet temperaturesoftheheattransferfluidshallbecalibrated 7.3 The anemometer used for wind velocity at least at yearly intervals. measurementoverthefrontsurfaceofthecollectorshall be calibrated at "regular intervals as per 5.3 MeasurementofAmbientAir Temperature recommendationsofmanufacturerofthe anemometer. The ambient air temperature shall be measured to an 8 PRESSURE MEASUREMENTS accuracyof±0.5°C. Adequatecare shall be takenfor mounting ofsensor so as to ensure that it is shaded 8.1 The inletpressuretothecollectorshall bemeasured from directand reflectedsolarradiation bymeansofa with adevice havingan accuracy of ± 3.5 kPa. white painted, well ventilated shelter, such as 8.2 The pressure drop across the solarcollector shall ~ meteorological screen, or by two concentric vertical be measured with a manometer havingan accuracy of metal pipes. The shelter itself shall be shaded and 0.25 mm ofwater/liquid column. placed at the mid height ofthe collector but at least one metreabovethe groundsurfaceto ensurethat itis 9 INSTRUMENTATIONIDATA RECORDERS awayfromthe influencesofgroundheating. Theshelter shall be placed on one side ofthe solar collector and 9.1 The smallest scale division ofthe instrument or within 10metresofit. instrument system shall not exceed two times the specified precision. For example, if the specified Ifair isforced overthe collectorby awindgenerator, precision is ±0.1DC,the smallestscaledivision shall the air temperatureshall be measured inthe outlet of not exceed 0.2°C. the wind generatoraridcheckswill be madeto ensure that this temperature does not deviate from the 9.2 Data Recorders surroundingair temperature by more than ± 1°C. Analogueand digital recordersshall have an accuracy 6 MEASUREMENTOF LIQUID FLOW RATE equal to or better than ± 0.5 percent ofthe full scale readingand haveatimeconstantofone secondor less. 6.1 The measurementaccuracyofthe liquid flow rate The peaksignalindicationshall bebetween50 and 100 shall be equal to or better than ± 1 percent ofthe percentoffull scale. measured value inmass units per unit time.: 9.3 Integrators 6.2 The flow metershall be calibratedoverthe range offluid flow rates and temperaturesto beused during Digitaltechniquesand electronicintegratorsshallhave collectortestingat least annually. an accuracy equal to or betterthan ± 1percent ofthe measured value. 7 MEASUREMENTOFWIND VELOCITY 9.4 InputImpedance 7.1 The wind velocity over the front surface ofthe solar collector shall be measured with an instrument The input impedance ofthe recorder shall be greater and associated readout device that can determine the than 1 000 times the impedance of the sensors or integrated average wind velocity for each test period IOmega-ohmswhich ever ishigher. to an accuracyof± 0.5 m/s. 10 ELAPSEDTIME 7.2 As the surrounding air speed outdoors is seldom Elapsed time measurements shall be made to an constant, an averageair speed isobtainedeitherbyan accuracy of± 0.2 percent. 3 Bureau of Indian Standards BIS isastatutory institution established underthe Bureau ofIndian Standards Act, 1986topromote harmonious development ofthe activities ofstandardization, marking and quality certification ofgoods and attending to connected matters in the country.. Copyright BIS has the copyright ofall its publications. No part ofthese publications may be reproduced in any form withoutthe priorpermission inwritingofBIS. Thisdoesnotprecludethefreeuse,inthecourseofimplementing the standard, ofnecessary details, such as symbols and sizes, type or grade designations. Enquiries relating to copyright be addressed to the Director (Publication), BIS. Review of Indian Standards Amendments are issued to standardsasthe need arises on the basis ofcomments. Standards are also reviewed periodically; a standard alongwith amendments isreaffirmed when such review indicates that no changes are needed; if the review indicates that changes are needed, itis taken up for revision. Users ofIndian Standards should ascertain that they are inpossession ofthe latestamendmentsoredition byreferringtothe latest issue of 'BIS Catalogue' and 'Standards: Monthly Additions'. This Indian Standard has been developed from Doc: No.ME 04 (0550). AmendmentsIssuedSince Publication' Amend No. DateofIssue Text Affected BUREAUOFINDIAN STANDARDS Headquarters: Manak Bhavan, 9BahadurShahZafar Marg,New Delhi 110002 Telegrams: Manaksanstha Telephones: 2323 0131,23233375,23239402 (Common toalloffices) Regional Offices: Telephone Central : Manak Bhavan, 9Bahadur ShahZafar Marg 23237617 { NEW DELHI 110002 23233841 Eastern .JtH.G.J.T. SchemeVIIM,V.J.P.Road,Kankurgachi 2337 8499,2337 8561 KOLKATA700054 . { 23378626,23379120 Northern : SCO 335-336, Sector34-A,CHANDIGARH 160022 603843 { 609285 Southern : C.IT Campus, IVCrossRoad,CHENNAI600113 2254 1216,22541442 { 22542519,22542315 Western : Manakalaya, E9MIDC,Marol,Andheri(East) {2832 9295, 2832 7858 MUMBAI400093 28327891,28327892 Branches : AHMEDABAD. BANGALORE.BHOPAL.BHUBANESHWAR.COIMBATORE.FARIDABAD. GHAZIABAD. GUWAHATI. HYDERABAD. JAIPUR. KANPUR. LUCKNOW. NAGPUR. NALAGARH. PATNA. PUNE. RAJKOT. THIRUVANANTHAPURAM. VISAKHAPATNAM. Printed at Simco Printing Press, Delhi

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