Gas meters - Turbine gas meters

This Standard specifies the range of application, the requirements and tests for the design, performance and safety of turbine gas meters having in line pipe connections for gas flow measurement. This standard applies to turbine gas meters used to measure the volume of fuel gases of the 1st and 2nd gas families at maximum working pressures up to 25 000 m3/h over a temperature range of at least -5 °C to +35 °C.

Gaszähler - Turbinenradgaszähler

Die vorliegende Norm legt die Messbedingungen fest, Anforderungen und Prüfungen hinsichtlich Konstruktion, Leistung und Sicherheit der axialen und radialen Turbinenradgaszähler mit mechanischen Anzeigegeräten, im Folgenden Zähler genannt, mit in einer Flucht liegenden Rohranschlüssen zur Gasdurchflussmessung.
Die vorliegende Norm gilt für Turbinenradgaszähler, die zur Volumenmessung von Brenngasen der 1. und 2. Gas-familie, deren Zusammensetzung in EN 437 angegeben ist, bei maximalen Betriebsdrücken bis zu 420 bar, Betriebsdurchflüssen bis zu 25 000 m3/h über einem Gastemperaturbereich von mindestens - 10 °C bis + 40 °C benutzt werden.
Soweit in dieser Norm nicht anders angegeben, sind alle dargestellten Drücke als Überdrücke zu verstehen.
Die Abschnitte 1 bis 7 sowie Anhang B gelten nur für Auslegung und Typprüfung mit Ausnahme von 6.2.2.3, 6.2.3.3, 6.6.1.1.2 und 6.6.2.2.2. Anhang C darf als Anleitung während der Durchführung der periodischen Prüfungen verwendet werden. Abschnitt 8 sowie die Anhänge D und E gelten für jeden Zähler vor Versand. Anhang A muss bei beiden, sowohl der Typ- als auch bei der Einzelprüfung, Anwendung finden.

Compteurs de gaz - Compteurs de gaz à turbine

La présente Norme européenne définit les conditions de mesure, les exigences et les essais applicables à la construction, à la performance et à la sécurité des compteurs de gaz à turbine axiale et radiale munis d'indicateurs mécaniques, désignés ci-après sous l'appellation « compteurs », ayant des raccordements sur des canalisations en ligne pour mesure de débit des gaz.
La présente Norme européenne s'applique aux compteurs de gaz à turbine utilisés pour mesurer le volume des gaz combustibles des première et deuxième familles de gaz, dont la composition est spécifiée dans l'EN 437, à des pressions maximales de service allant jusqu'à 420 bar, à des débits réels allant jusqu'à 25 000 m3/h sur une plage de températures du gaz d'au moins ­ 10 °C à + 40 °C.
Sauf indication contraire, toutes les pressions utilisées dans la norme sont relatives.
Les articles 1 à 7 et l'annexe B concernent uniquement la conception et les essais de modèle, à l'exception de 6.2.2.3, 6.2.3.3, 6.6.1.1.2 et 6.6.2.2.2. L'annexe C peut servir de guide pour les essais périodiques lors de l'utilisation. L'article 8 ainsi que les annexes D et E concernent les essais individuels avant livraison. L'annexe A doit être utilisée aussi bien pour les essais de modèle que pour les essais individuels.

Plinomeri - Turbinski plinomeri

General Information

Status
Withdrawn
Publication Date
16-Apr-2002
Withdrawal Date
27-Mar-2018
Technical Committee
Current Stage
9960 - Withdrawal effective - Withdrawal
Completion Date
28-Mar-2018

RELATIONS

Effective Date
22-Dec-2008
Effective Date
01-Feb-2017
Effective Date
04-Apr-2018

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2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Plinomeri - Turbinski plinomeriGaszähler - TurbinenradgaszählerCompteurs de gaz - Compteurs de gaz a turbineGas meters - Turbine gas meters91.140.40Sistemi za oskrbo s plinomGas supply systemsICS:Ta slovenski standard je istoveten z:EN 12261:2002SIST EN 12261:2004en01-februar-2004SIST EN 12261:2004SLOVENSKI

STANDARD
SIST EN 12261:2004

EUROPEAN STANDARDNORME EUROPÉENNEEUROPÄISCHE NORMEN 12261April 2002ICS 17.120.10English versionGas meters - Turbine gas metersCompteurs de gaz - Compteurs de gaz à turbineGaszähler - TurbinenradgaszählerThis European Standard was approved by CEN on 2 September 2001.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards may be obtained on application to the Management 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 translationunder the responsibility of a CEN member into its own language and notified to the Management Centre has the same status as the officialversions.CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece,Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMITÉ EUROPÉEN DE NORMALISATIONEUROPÄISCHES KOMITEE FÜR NORMUNGManagement Centre: rue de Stassart, 36

B-1050 Brussels© 2002 CENAll rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 12261:2002 ESIST EN 12261:2004

EN 12261:2002 (E)2Contents1Scope..............................................................................................................................................................32Normative references....................................................................................................................................33Terms, definitions and symbols...................................................................................................................53.1Terms and definitions...................................................................................................................................53.2Symbols..........................................................................................................................................................84Meter classification.......................................................................................................................................94.1Flange pressure ratings................................................................................................................................94.2Gas meter sizes, rangeability and connection diameter sizes.................................................................94.3Connections and dimensions.....................................................................................................................104.4Temperature ranges....................................................................................................................................115Metrological performance requirements...................................................................................................115.1General..........................................................................................................................................................115.2Type testing..................................................................................................................................................116Design and material requirements.............................................................................................................176.1General..........................................................................................................................................................176.2Robustness..................................................................................................................................................176.3Resistance to environmental conditions..................................................................................................226.4Removable meter mechanisms..................................................................................................................246.5Indicating devices and accessories..........................................................................................................256.6Pressure and temperature tappings..........................................................................................................266.7Lubrication...................................................................................................................................................277Meter output.................................................................................................................................................287.1General..........................................................................................................................................................287.2Indicating device..........................................................................................................................................287.3Pulse generator............................................................................................................................................297.4Output shaft.................................................................................................................................................307.5Test element.................................................................................................................................................318Marking.........................................................................................................................................................318.1General..........................................................................................................................................................318.2Data plate......................................................................................................................................................318.3Direction of flow...........................................................................................................................................328.4Working position.........................................................................................................................................328.5Other connections.......................................................................................................................................32Annex A (normative)

Test facility specifications...................................................................................................33Annex B (normative)

Perturbation testing..............................................................................................................34Annex C (informative)

Recommendations for use.................................................................................................40Annex D (normative)

Individual factory testing.....................................................................................................41Annex E (normative)

Metrological requirements and tests for each meter prior to dispatch(Individual meter testing)............................................................................................................................42SIST EN 12261:2004

EN 12261:2002 (E)3ForewordThis document (EN 12261:2002) has been prepared by Technical Committee CEN/TC 237 "Gas meters",the secretariat of which is held by BSI.This European Standard shall be given the status of a national standard, either by publication of anidentical text or by endorsement, at the latest by October 2002, and conflicting national standards shallbe withdrawn at the latest by October 2002.In the preparation of this European Standard, the content of ISO 9951, the content of OIML Publication,"International Recommendation 6" and "International Recommendation 32" and the content of memberbodies national standards on turbine meters have been taken into account.The metrological aspects of this European Standard may be subject to amendments to bring it into linewith the proposed Measuring Instruments Directive (MID).Electronic Indexes are not specifically covered by this Standard, however, work to produce a Standardcovering these devices is in progress under CEN/TC 237.Annexes A, B, D and E are normative. Annex C is informative.This standard includes a Bibliography.According to the CEN/CENELEC Internal Regulations, the national standards organizations of thefollowing countries are bound to implement this European Standard: Austria, Belgium, Czech Republic,Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands,Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom.1 ScopeThis European Standard specifies the measuring conditions, requirements and tests for the construction,performance and safety of axial and radial turbine gas meters with mechanical indicating devices, hereinafter referred to as a meter(s), having in-line pipe connections for gas flow measurement.This European Standard applies to turbine gas meters used to measure the volume of fuel gases of the1st and 2nd gas families, the composition of which is specified in EN 437, at maximum working pressuresup to 420 bar, actual flow rates up to 25 000 m3/h over a gas temperature range of at least –10 °C to+40 °C.Unless otherwise specified in this standard, all pressures used are gauge.Clauses 1 to 7 and annex B are for design and type testing only, with the exception of 6.2.2.3, 6.2.3.3,6.6.1.1.2 and 6.6.2.2.2. Annex C may be used to provide guidance on periodic tests during use. Clause 8and annexes D and E are for each meter prior to dispatch. Annex A shall be used for both type andindividual testing.2 Normative referencesThis European Standard incorporates by dated or undated references provisions from other publications.These normative references are cited at the appropriate places in the text and the publications are listedhereafter. For dated references subsequent amendments to or revisions of any of these publicationsapply to this European standard only when incorporated in it by amendment or revision. For undatedreferences the latest edition of the publication referred to applies (including amendments).EN 437, Test gases — Test pressures — Appliance categoriesSIST EN 12261:2004

EN 12261:2002 (E)4EN 10204, Metallic products — Types of inspection documentsEN 50014, Electrical apparatus for potentially explosive atmospheres — General requirementsEN 50020, Electrical apparatus for potentially explosive atmospheres — Intrinsic safety "I"EN 60529, Degrees of protection provided by enclosures (IP code) (IEC 60529:1989)EN 60947-5-6, Low-voltage switchgear and controlgear — Part 5-6: Control circuit devices and switchingelements — DC interface for proximity sensors and switching amplifier (NAMUR) (IEC 60947-5-6:1999)EN ISO 5167-1:1995, Measurement of fluid flow by means of pressure differential devices —Part 1: Orifice plates, nozzles and Venturi tubes inserted in circular cross-section conduits running full(ISO 5167-1:1991)EN ISO 9001, Quality management systems — Requirements (ISO 9001:2000)ISO 3, Preferred numbers — Series of preferred numbersISO 2768-1:1989, General tolerances — Part 1: Tolerances for linear and angular dimensions withoutindividual tolerance indicationsISO guide to the expression of uncertainty in measurementEN 119000, Generic specification — Dry and mercury wetted reed contact unitsSIST EN 12261:2004

EN 12261:2002 (E)53 Terms, definitions and symbols3.1 Terms and definitionsFor the purposes of this European Standard, the following terms and definitions apply.3.1.1turbine gas metermeasuring device in which the dynamic forces of the flowing gas cause a turbine wheel to rotate with aspeed as a function of the volume flow rate. The number of revolutions of the turbine wheel is the basisfor the indication of the volume passed through the meter3.1.2measured quantityvolume in cubic metres, at metering conditions3.1.3volume flow ratevolume at metering conditions divided by time3.1.4rangeabilitythe ratio between Qmin and Qmax, i.e. the minimum and maximum flow rate respectively for which themeter performs within the maximum permissible errors3.1.5average velocityvolume flow rate divided by the cross-sectional area of the meter connections3.1.6casingpressure containing structure of the meter3.1.7 pressures and temperatures3.1.7.1metering pressure

(pm)absolute gas pressure to which the indicated volume of gas is related3.1.7.2operating pressuregas pressure within the piping containing the meter3.1.7.3working pressure rangeallowable pressure range over which the meter is calibrated and performs within the metrologicalrequirements3.1.7.4working temperature rangerange of metering temperatures over which the meter operates within the metrological requirements3.1.7.5maximum design pressure (pmax)pressure on which design calculations are basedSIST EN 12261:2004

EN 12261:2002 (E)63.1.8designation3.1.8.1DN-designationnumerical designation of size for components of a pipework system, which is used for referencepurposes. It comprises the letters DN followed by a dimensionless whole number which is indirectlyrelated to the physical size, in millimetres, of the bore or outside diameter of the end connections3.1.8.2PN-designationalphanumeric term used for reference purposes related to a combination of mechanical and dimensionalcharacteristics of a component of a pipework system with regard to pressure. It comprises the letters PNfollowed by a dimensionless whole number3.1.9metering conditionsconditions of the gas prevailing at the point of the measurement (e.g.: temperature and pressure of themeasured gas in the meter)3.1.10Reynolds number (Re)number referring to the flow conditions:v

= R´´35370,ewhere the value of D is given by the internal pipe diameter. The parameters (variables) in the aboveequation and their units are defined in Table 13.1.11error of

indicationindication of a turbine meter minus the reference value of the measurandErrors (E) are expressed as relative values (as a percentage) by the ratio of the difference between theindicated volume (Vi) and a reference volume (Vc) of the gas which has passed through the gas meter tothis latter value: 100

V = Ecci´-3.1.12pressure lossnon-recoverable pressure drop caused by the presence of the turbine meter in the conduit3.1.13pulse valuenumber of pulses per cubic metre indicated3.1.14gas families3.1.14.11st familya gas having a Wobbe index between:23,8 MJ × m-3 and 31,4 MJ × m-3according to EN 437 related on gross calorific valueSIST EN 12261:2004

EN 12261:2002 (E)73.1.14.22nd familya gas having a Wobbe index between:41,3 MJ × m-3 and 57,9 MJ × m-3according to EN 437 related on gross calorific valueSIST EN 12261:2004

EN 12261:2002 (E)83.2 SymbolsThe symbols and subscripts used hereafter in this European Standard are specified in Table 1.Table 1 — SymbolsSymbolsRepresented quantityUnitcPressure loss coefficient depending on meter typemm-4dRelative density of the gas (air = 1)-DInside diameter meter outlet/inletmmD1Inside diameter pipemmEError%FForce (bending moment)NF´Force (torsional moment)NICurrentALLength of the lever arm (bending moment)mmL´Length of the lever arm (torsional moment)mmMTorqueNmpPressurePa, barQVolume flow ratem3/hReReynolds number-tTemperature°CUBBattery voltageVVVolumem3Kinematic viscositym2

s -1Density of the gaskg

m –3Subscripts:iSummation indexmMetering conditions of the gasmaxMaximum valueminMinimum valuesSpecified conditionstTransitionalSIST EN 12261:2004

EN 12261:2002 (E)94 Meter classification4.1 Flange pressure ratingsFlanges shall be designed according to PN Designation or ANSI class rating (see Table 2).Table 2 — Flange pressure ratingsPN DesignationANSI class rating1012516-2015025-40-5030064-100-110600150900250-26015004202500This table is based on EN 1333 resp. ISO 7005-1.The use of the following pressure ratings is recommended:10 - 16 - 20 - 25 - 40 - 50 - 100 - 150 - 250 - 420.4.2 Gas meter sizes, rangeability and connection diameter sizesGas meters shall be classified according to maximum and minimum flow rates and nominal diameters asshown in Table 3.The maximum and minimum flow rates shall be specified for the gas density for which the meter willoperate within the specifications of meter performance defined in clause 5.NOTEThe maximum flow rate in cubic meters per hour (m3/h) is a number in R 5 of the sets of preferrednumbers listed in ISO 3 (the value of 63 has been rounded to 65).SIST EN 12261:2004

EN 12261:2002 (E)10Table 3 — Authorized values of maximum flow rates, corresponding minimum flow rates andnominal diametersRangeabilityNominal diameters DN1:101:201:301:50Qmin (m3/h)QmaxABC(m3/h)40421,30,82550656321,35010010532508016016853508010025025138580100400402013880100150650653220131001501 0001005032201502001 6001608050321502002502 50025013080502002503004 000400200130802503004006 50065032020013030040010 0001 00050032020040050016 0001 60080050032050060025 0002 5001 300800500600750Ahigh speed versionBnormal speed version (preferred)Clow speed version4.3 Connections and dimensionsThe inlet and outlet of the meter shall have the same nominal diameter and connection type.The preferred overall length in millimetres of the meter between inlet and outlet connections is 3 DN.Tolerances are given in ISO 2768-1:1989, “Designation C“.The preferred length in millimetres of 3 DN for the meter shall not be exceeded. For shorter meters themanufacturer shall be able to provide a “make up spool piece“ to bring their body lengths up to thepreferred length, where requested.The maximum overall distance in millimetres measured from the extremity of the protruding parts to themeter axis should not exceed 150 plus 1,5 DN.For flange connections refer to Table 2.SIST EN 12261:2004

EN 12261:2002 (E)114.4 Temperature rangesThe gas and the ambient temperature ranges for which the meter is designed to perform within thestandard performance specification shall be stated.5 Metrological performance requirements5.1 GeneralEach type of meter shall be subjected to the series of tests specified in 5.2 to establish the metrologicalperformance of the type of meter. If one type of meter comprises a range of sizes of the same basicdesign and a range of metering conditions, the type test may be performed on a limited number ofsample meters (1 to 6 samples irrespective of size) being representative for that range of meter sizes andmetering conditions.Each meter conforming to an approved type shall be tested individually according to annex E. The resultsof the tests obtained in 5.2 and annex E shall be available on request together with a statement of theconditions under which the test took place.The meter shall be fitted with all components which may affect the metrological performance.General requirements for the test facility to be used for the type test are given in annex A.Where the text refers to a gas for flow tests this means air or a gas from the 1st or 2nd gas family or anyother gas provided it is yielding similar metrological results at a Reynolds number within ± 5 % of theReynolds number at the foreseen metering conditions.The total uncertainty of the equipment used to measure the error of indication shall be calculatedaccording to ISO Guide.5.2 Type testing5.2.1 Error of indication5.2.1.1 RequirementsThe error of indication of the meter shall be in absolute values

less

than the maximum permissibleerrors specified in Table 4, taking account of Table 5.Table 4 — Maximum permissible errorsFlow rate QMaximum permissible errorsQmin £ Q < Qt± 2 %Qt £ Q £ Qmax± 1 %Table 5 — Transitional flow rate QtRangeabilityQt1 : 100,20 × Qmax1 : 200,20 × Qmax1 : 300,15 × Qmax³1 : 500,10 × QmaxSIST EN 12261:2004

EN 12261:2002 (E)12If tests at more than one pressure are carried out, the difference between the results of the tests between0,25 × Qmax and Qmax shall not exceed 0,5 % for meters with DN > 100 or 1,0 % for meters with DN £ 100.If a meter has been certified for one working pressure range it is deemed to be certified for any smallerworking pressure range.If a meter is certified for one rangeability it is deemed to be certified for any lower rangeability.5.2.1.2 TestBefore type testing, a meter shall undergo a run-in-period of 50 hours at a flow rate of at least0,5 × Qmax.The test consists of determining the error of indication of the complete meter at the flow rates given inTable 6.For a meter type specified for measurement in a pressure range below or equal to 4 bar the error ofindication test shall be carried out with a gas at atmospheric conditions (± 100 mbar).For a meter type specified for measurement in a pressure range extended above 4 bar the error ofindication test shall be carried out with a gas in the range of the specified metering conditions. The testsshall be carried out at least at the lowest and the highest working pressure specified by the manufacturer.However, for specified maximum pressures above 50 bar a test at 50 bar is deemed acceptable.Table 6 — Test flow rates in % of QmaxRangeability1 : 101 : 201 : 301 : 5023555101010152525252540404040707070701001001001005.2.2 Stability5.2.2.1 RequirementsIn the flow rate range from 0,25 × Qmax to Qmax the variation of the error of indication of the meter at eachflow rate shall stay within a span of 0,2 %.SIST EN 12261:2004

EN 12261:2002 (E)135.2.2.2 TestThe error of indication of the meter shall be determined at various flow rates in the following order: 0,25 ×Qmax, 0,70 × Qmax, 0,40 × Qmax, Qmax, where the change from 0,4 × Qmax to Qmax is done via1,10 × Qmax, in order to approach Qmax from a higher flow rate. At each flow rate the error shall bedetermined three times without changing the flow rate. The cycle shall be repeated three

times. The testshall be carried out with a gas at atmospheric conditions (± 100 mbar) or at the lowest pressuredesignated on the meter.The nine resulting errors of indication at each flow rate shall be within a span of 0,2 %.5.2.3 Linearity5.2.3.1 RequirementsFor the test flow rates from 0,25 × Qmax to Qmax at each test pressure the differences between the highestand the lowest error of indication shall not exceed the values specified in Table 7.Table 7 — Allowable differences between the highest and lowest error of indication at each testpressurePressureSize< 4 bar> 4 bar< DN 1001,0 %0,5 %> DN 1001,0 %0,3 %5.2.3.2TestIn order to determine if the linearity requirement is fulfilled the value of the errors found at each flow rateaccording to 5.2.1.2 shall be taken.5.2.4 Endurance5.2.4.1 RequirementsMeters shall retain the accuracy of their metrological characteristics, within defined limits, over theirexpected life. To prove this the meters shall undergo an endurance test.The difference in error of indication between the start and end of the test shall be less than one third ofthe maximum permissible error given in Table 4.5.2.4.2 TestOne to six sample meters of each type irrespective of size shall be used for the endurance test.Meters shall be tested with their indicating devices fitted.The duration of the test shall be such that each meter measures a volume corresponding to 1 000 h ofoperation of the meter at the maximum flow rate; the test shall be completed within 2 months.For a meter type intended for operation in a pressure range below or equal to 4 bar the test shall becarried out with a gas at a

pressure of 4 bar or its maximum working pressure whichever is the lower.For a meter type intended for operation in a pressure range extended above 4 bar, the test shall becarried out with a gas at a minimum pressure of 8 bar or at its maximum working pressure whichever islower.SIST EN 12261:2004

EN 12261:2002 (E)14At the start of the test all meters shall conform to 5.2.1.1 and 5.2.2.1.At the end of the test the error of indication of the meters shall be determined again under the sameconditions and at the same test facility as at the start of the test.5.2.5 Meter position5.2.5.1 RequirementsUnless it is specified on the meter that it is to be used only for certain mounting positions in the line, foreach type of meter it shall be established whether the position of the meter influences the measuringbehaviour of the meter. The following positions shall be considered: horizontal, vertical flow-up, verticalflow-down.5.2.5.2 TestThe test consists of 2 parts.a) The meter shall be tested in each position to be considered according to the procedure in 5.2.1. Thetest shall take place at the lowest working pressure of the meter. The difference in test results shallbe less

than one third of the maximum permissible error limits for the flow rates above and below Qt.b) A sample meter shall be subjected to the endurance test specified in 5.2.4 in each position.NOTEDifferent sample meters may be used for each test position.5.2.6 Temporary overload5.2.6.1 RequirementsThe meter shall be designed to be capable of occasionally running 20 % above the maximum flow ratewithin the range of pressure and temperature for which it is rated without influence on the error ofindication of the meter.5.2.6.2 TestThe meter shall run at a flow rate of 1,2 × Qmax for a time period of 1 h. The test shall be carried out at thesame pressures as the error of indication test in 5.2.1.After this 1 hour test, the error of indication in the flow rate range from 0,25 × Qmax to Qmax shall remainwithin the span specified for the stability test in 5.2.2.5.2.7 Temperature range5.2.7.1 RequirementsThe working temperature ranges over which the meter is designed to perform within the standardperformance specification shall be stated by the manufacturer.This temperature range shall be at least from –1 °C to +40 °C.SIST EN 12261:2004

EN 12261:2002 (E)155.2.7.2 TestThe test consists of three parts.a) MaterialsThe manufacturer shall demonstrate that all materials of which the meter is designed are capable ofwithstanding the extreme temperatures of the specified temperature range.b) Test on the indicating deviceThe indicating device, including as many parts of the gear train as possible from the design of the meter,shall be taken from the meter and placed in a temperature cabinet. It shall be connected to a drive unitcapable of operating the indicating device.The indicating device shall then be exposed to a 24 hour cyclic temperature variation between the upperand lower temperature limit, maintaining the relative humidity above 95 % during the temperature changeand low temperature phases, and at 93 % at the upper temperature phase.NOTECondensation will occur during the temperature rise.The 24 hour cycle consists of:¾ temperature rise during 3 hours;¾ temperature maintained at the upper value until 12 hours from the start of the cycle;¾ temperature lowered to lower value within 3 hours;¾ temperature maintained at the lower value until 24 hour cycle is completed.During and after the temperature cycle the indicating device shall operate without problems.c) Test of the complete meterThe error of indication of the meter shall be determined at least at one gas temperature differing by aminimum of 15 K higher and one differing by a minimum of 15 K lower from the gas temperature at whichthe test given in 5.2.1.2 took place. Care shall be taken that the meter temperature has been stabilized atthis test temperature. The difference between the errors of indication from this test and from the testgiven in 5.2.1.2 shall be less than one half the maximum permissible error given in Table 4.The test shall be carried out at the flow

rates Qmin or 0,05 × Qmax, whichever is greater, and at0,40 × Qmax.Two sample meters of each type, the size of which does not exceed DN 150, shall be used for the test.The test shall be carried out at atmospheric conditions (± 100 mbar).5.2.8 Installation conditions5.2.8.1 RequirementsIn order to assess the sensitivity of the meter performance to upstream installation conditions, each typeof meter shall be subjected to the standard tests described in annex B „Perturbation testing“.The errors of indication obtained during disturbed flow conditions downstream of the pertubation unitsshall not differ by more than one third of the maximum permissible error limits given in Table 4, from theerror of indication obtained with an undisturbed upstream flow condition as obtained in 5.2.1.Any additional pipe inlet lengths and/or flow conditioners necessary to meet this requirement shall bespecified by the manufacturer. These components together with the meter consitute a “meter package”.SIST EN 12261:2004

EN 12261:2002 (E)165.2.8.2 TestThe test is specified in annex B.5.2.9 Maximum permissible pressure loss5.2.9.1 RequirementsPressure loss data for the meter type and size or meter package, as appropriate, shall be provided by themanufacturer.The pressure loss of a new turbine meter shall, with air at atmospheric conditions (± 100 mbar) as testmedium, and at flow rate Qmax be less than the values specified in Table 8.Table 8 — Maximum pressure loss values across the meter at Qmax with atmospheric air as testmediumNominal diametersPressure loss (Pa)according to C1 000according to B1 500according to A2 500Definitions A, B, C see Table 35.2.9.2 TestThe pressure loss across the meter, including an

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