Gas meters - Thermal-mass flow-meter based gas meter

This European Standard specifies requirements and tests for the construction, performance and safety of class 1,5 Capillary Thermal-Mass Flow sensor gas meters (hereinafter referred to as meter(s)). This applies to meters having co-axial single pipe, or two pipe connections, that are used to measure volumes of fuel gases, which are within the limits of the test gases of the 2nd and/or 3rd family according to EN 437.  
These meters have a maximum working pressures not exceeding 0,5 bar and a maximum flowrate not exceeding 160 m3.h−1 over a minimum ambient temperature range of −10 °C to +40 °C and a gas temperature range as specified by the manufacturer with a minimum range of 40 K.

Gaszähler - Thermische Massendurchflussgaszähler

Dieses Dokument legt Anforderungen und Prüfungen für die Konstruktion, Leistung Sicherheit und Herstellung von batteriebetriebenen thermischen Kapillar-Massendurchflusssensor-Gaszählern der Klasse 1,5 (im Nachfolgenden als Zähler bezeichnet) fest. Es gilt für Zähler mit koaxialen Einstutzen- oder Zweistutzenanschlüssen zur Volumenmessung von Brenngasen aus der Gruppe der Prüfgase der 2. und/oder 3. Familie nach EN 437:2018.
Im Allgemeinen gilt der Begriff "thermische Massendurchflusszähler" für durchflussmessende Geräte, die zur Erfassung und Anzeige des Gasdurchflusses, wie in ISO 14511 festgelegt, Wärmeübertragung nutzen.
ANMERKUNG 1   Obwohl der Begriff "Masse" in der Definition des Messprinzips enthalten ist, messen durch dieses Dokument abgedeckte Gaszähler Gas anhand der Basisbedingungen Temperatur und Druck.
Diese Zähler weisen einen maximalen Betriebsdruck bis 0,5 bar und einen maximalen Durchfluss bis 160 m3 ∙ h−1 über einen Umgebungstemperaturbereich von mindestens −10 °C bis +40 °C auf, sowie einen Gastemperaturbereich, der den Spezifikationen des Herstellers entspricht, jedoch mindestens 40 °C umfasst.
Dieses Dokument gilt für Zähler, die das Volumen bei Basisbedingungen anzeigen und an Standorten mit nicht signifikanten Schwingungs- und Stoßbelastungen installiert sind. Es gilt für Zähler an:
-   geschlossenen Standorten (innen oder außen mit dem vom Hersteller vorgeschriebenen Schutz) mit kondensierender Feuchtigkeit oder nicht kondensierender Feuchtigkeit;
oder, bei entsprechender Angabe durch den Hersteller an:
-   offenen Standorten (außen ohne Abdeckung) mit kondensierender Feuchtigkeit oder nicht kondensierender Feuchtigkeit;
und an Standorten mit elektromagnetischen Störungen, wie sie beim Gebrauch in Wohn- und Gewerbegebäuden sowie Gebäuden der Leichtindustrie auftreten können.
Für Zähler, die nicht umgewertete Volumina anzeigen, kann auf Anhang C verwiesen werden.
Soweit in dieser Norm nicht anders angegeben, sind alle dargestellten Drücke als Überdrücke zu verstehen.
Anforderungen an elektronische Zählwerke, Ventile und zusätzliche Anforderungen für in den Zähler integrierte Batterien und andere Zusatzfunktionen sind in EN 16314:2013 angegeben.
Sofern für einen bestimmten Test nicht anderweitig angegeben, werden die Tests mit Zählern durchgeführt, die vom Hersteller vorgesehene Zusatzfunktionsgeräte besitzen.
Abschnitt 1 bis Abschnitt 13 gelten nur für Bauart und Typprüfung.

Compteurs de gaz - Compteur de gaz thermique de débit massique

Le présent document spécifie les exigences et les essais pour la construction, le fonctionnement et la sécurité des compteurs de gaz à capteur massique thermique capillaire de classe 1.5 (ci-après désigné(s) compteur(s)). Il s'applique aux débitmètres à raccordement monotube coaxial ou bitube, utilisés pour mesurer les volumes de gaz combustibles de la 2e et/ou 3e famille, tels que définis dans l'EN 437:2018.
En général, le terme « débitmètre massique thermique » s'applique aux appareils de mesurage de débit qui mesurent et indiquent le débit de gaz à l'aide du transfert thermique, tels que définis dans l'ISO 14511.
NOTE 1   Bien que le mot « masse » soit présent dans la définition du principe de mesure, les compteurs de gaz couverts par le présent document fournissent un mesurage du gaz dans les conditions de base de température et de pression.
Ces débitmètres ont une pression de service maximale ne dépassant pas 0,5 bar et un débit maximal ne dépassant pas 160 m3/h dans une plage de température ambiante minimale comprise entre −10 °C et +40 °C et une plage de température du gaz telle que spécifiée par le fabricant avec une plage minimale de 40°C.
Le présent document s'applique aux débitmètres indiquant le volume dans les conditions de base, installés dans des lieux exposés à des vibrations et des chocs peu importants. Il s'applique aux débitmètres dans :
-   les lieux fermés (intérieurs ou extérieurs avec protection, tel que spécifié par le fabricant) avec humidité de condensation ou une humidité sans condensation ;
ou, si spécifié par le fabricant :
-   les lieux ouverts (extérieurs sans couvercle) avec humidité de condensation ou avec humidité sans condensation ;
et dans les lieux avec des perturbations électromagnétiques susceptibles d'être présentes dans les utilisations résidentielles, commerciales et celle de l'industrie légère.
Pour les débitmètres qui indiquent un volume non converti, on peut se référer à l'Annexe C.
Sauf spécification contraire, toutes les pressions données par le présent document sont des pressions effectives.
Les exigences pour les index électroniques, les vannes et les exigences supplémentaires pour les batteries incorporées dans le débitmètre et toute autre fonctionnalité supplémentaire sont données dans l'EN 16314:2013.
Sauf spécification contraire dans un essai particulier, les essais sont réalisés sur des débitmètres comprenant des appareils à fonctionnalités supplémentaires prévues par le fabricant.
Les Articles 1 à 13 concernent uniquement les essais de conception et de type.

Plinomeri - Plinomer na osnovi termičnega merjenja masnega toka

Ta evropski standard določa zahteve in preskuse za konstrukcijo, delovanje ter varnost plinomerov na osnovi termičnega merjenja masnega toka razreda 1,5 (v nadaljnjem besedilu: merilnik(-i)). To velja za merilnike s koaksialnim enocevnim ali dvocevnim priključkom, ki se uporabljajo za merjenje volumnov gorivnih plinov, ki so v mejah preskusnih plinov 2. in/ali 3. skupine v skladu s standardom EN 437.  
Ti merilniki imajo najvišji delovni tlak, ki ne presega 0,5 bara, in največji pretok, ki ne presega 160 m3.h−1 v najmanjšem razponu temperature okolice od –10 °C do +40 °C in temperaturnem območju plina, kot ga določa proizvajalec, z minimalnim razponom 40 K.

General Information

Status
Published
Public Enquiry End Date
02-Jun-2020
Publication Date
11-Jan-2022
Technical Committee
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
07-Jan-2022
Due Date
14-Mar-2022
Completion Date
12-Jan-2022

Buy Standard

Standard
EN 17526:2022
English language
82 pages
sale 10% off
Preview
sale 10% off
Preview
e-Library read for
1 day
Draft
prEN 17526:2020
English language
88 pages
sale 10% off
Preview
sale 10% off
Preview
e-Library read for
1 day

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN 17526:2022
01-februar-2022
Plinomeri - Plinomer na osnovi termičnega merjenja masnega toka
Gas meters - Thermal-mass flow-meter based gas meter
Gaszähler - Thermische Massendurchflussgaszähler
Compteurs de gaz - Compteur de gaz thermique de débit massique
Ta slovenski standard je istoveten z: EN 17526:2021
ICS:
91.140.40 Sistemi za oskrbo s plinom Gas supply systems
SIST EN 17526:2022 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------
SIST EN 17526:2022

---------------------- Page: 2 ----------------------
SIST EN 17526:2022


EN 17526
EUROPEAN STANDARD

NORME EUROPÉENNE

December 2021
EUROPÄISCHE NORM
ICS 91.140.40
English Version

Gas meter - Thermal-mass flow-meter based gas meter
Compteurs de gaz - Compteur de gaz basé sur un Gaszähler - Thermische Massendurchflussgaszähler
débitmètre massique par effet thermique
This European Standard was approved by CEN on 11 July 2021.

CEN members are bound to comply with the 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 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
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and
United Kingdom.





EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2021 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 17526:2021 E
worldwide for CEN national Members.

---------------------- Page: 3 ----------------------
SIST EN 17526:2022
EN 17526:2021 (E)
Contents Page
European foreword . 4
1 Scope . 5
2 Normative references . 5
3 Terms, definitions and symbols . 8
3.1 Terms and definitions . 8
3.2 Symbols . 12
4 Working conditions . 13
4.1 General . 13
4.2 Base conditions . 13
4.3 Flow range . 13
4.4 Maximum working pressure . 14
4.5 Temperature range . 14
4.6 Range of gases . 15
4.7 Installation orientation . 15
5 Metrological performance . 15
5.1 General . 15
5.2 Test mode comparison . 16
5.3 Permissible errors . 17
5.4 Gas-air relationship . 19
5.5 Pressure absorption . 20
5.6 Metrological stability . 21
5.7 Immunity to contaminants in gas stream (dust test) . 22
5.8 Flow disturbances . 25
5.9 Zero flow . 29
5.10 Reverse flow . 30
5.11 Low flow registration (starting flow rate) . 30
5.12 Overload flow rate . 30
5.13 MM - Pulsed (unsteady) flow . 31
6 Construction and materials . 31
6.1 Mechanical interference . 32
6.2 Unauthorized interference . 32
6.3 Robustness of meter case . 33
6.4 Connections . 37
6.5 Resistance to vibration . 42
6.6 Corrosion protection. 44
6.7 Flame retardance of external surfaces . 45
6.8 Requirements for rubber components in the gas path . 46
6.9 Resistance to storage temperature range . 46
6.10 Resistance to toluene/iso-octane vapour. 46
6.11 Resistance to water vapour . 48
6.12 Ageing . 49
7 Optional features . 50
7.1 Pressure measuring point . 50
7.2 Electrical insulating feet (optional) . 51
7.3 Resistance to high ambient temperatures . 51
2

---------------------- Page: 4 ----------------------
SIST EN 17526:2022
EN 17526:2021 (E)
7.4 Additional functionalities (if fitted) . 53
7.5 Use in hazardous zones . 54
8 Index . 54
8.1 Recording and storage . 54
8.2 Display . 54
8.3 Display functionality . 55
8.4 Non-volatile memory . 56
9 Marking . 57
9.1 All meters. 57
9.2 Two-pipe meters . 57
9.3 Durability and legibility of marking and labels . 58
9.4 Indelibility of marking . 59
10 Software . 59
10.1 Requirements . 59
10.2 Test . 59
11 Communications . 60
11.1 General . 60
11.2 Metrological influence of radio communication function . 60
11.3 Test mode . 61
11.4 Data optical port (optional) . 61
11.5 Galvanic port (optional) . 61
11.6 Diagnostics . 61
12 Battery . 63
12.1 General . 63
12.2 Additional requirements . 63
13 Immunity to electromagnetic disturbances . 63
13.1 General . 63
13.2 Electrostatic discharge . 64
13.3 Radio frequency electromagnetic field . 64
13.4 Electromagnetic induction (power frequency) . 65
13.5 Electromagnetic induction (pulsed field) . 65
13.6 Radio interference suppression . 65
14 Instructions . 66
15 Meters supplied for testing . 66
16 Production requirements . 69
Annex A (informative) Key physical property of gases for meter performance testing . 70
Annex B (normative) Gases for meter performance testing . 72
Annex C (informative) Meters without temperature or pressure conversion . 74
Annex D (normative) Production requirements for gas meters. 75
Annex ZA (informative) Relationship between this European Standard and the Essential
Requirements of EU Directive 2014/32/EU Measuring Instruments Directive aimed
to be covered . 77
Bibliography . 82

3

---------------------- Page: 5 ----------------------
SIST EN 17526:2022
EN 17526:2021 (E)
European foreword
This document (EN 17526:2021) 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 an
identical text or by endorsement, at the latest by June 2022, and conflicting national standards shall be
withdrawn at the latest by June 2022.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document has been prepared under a Standardization Request given to CEN by the European
Commission and the European Free Trade Association, and supports essential requirements of EU
Directive(s) / Regulation(s).
For relationship with EU Directive(s) / Regulation(s), see informative Annex ZA, which is an integral part
of this document.
Any feedback and questions on this document should be directed to the users’ national standards body.
A complete listing of these bodies can be found on the CEN website.
According to the CEN-CENELEC Internal Regulations, the national standards organisations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia,
Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland,
Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of North
Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United
Kingdom.

4

---------------------- Page: 6 ----------------------
SIST EN 17526:2022
EN 17526:2021 (E)
1 Scope
This document specifies requirements and tests for the construction, performance, safety and production
of battery powered class 1,5 Capillary Thermal-Mass Flow sensor gas meters (hereinafter referred to as
meter(s)). This applies to meters having co-axial single pipe, or two pipe connections, which are used to
measure volumes of fuel gases of the 2nd and/or 3rd family, as given in EN 437:2018.
In general, the term “thermal mass flow meters” applies to a flow-measuring device using heat transfer
to measure and indicate gas flowrate, as defined in ISO 14511.
NOTE 1 Although the word “mass” is present in the definition of the measurement principle, gas meters covered
by this document provide measurement of gas at base conditions of temperature and pressure.
These meters have a maximum working pressure not exceeding 0,5 bar and a maximum flowrate not
3
exceeding 160 m /h over a minimum ambient temperature range of −10 °C to +40 °C and a gas
temperature range as specified by the manufacturer with a minimum range of 40 °C.
This document applies to meters indicating volume at base conditions, which are installed in locations
with vibration and shocks of low significance. It applies to meters in:
— closed locations (indoor or outdoor with protection, as specified by the manufacturer) with
condensing humidity or with non-condensing humidity;
or, if specified by the manufacturer:
— open locations (outdoor without any covering) both with condensing humidity or with non-
condensing humidity;
and in locations with electromagnetic disturbances likely to be found in residential, commercial and light
industrial use.
For meters which indicate unconverted volume, reference can be made to Annex C.
Unless otherwise stated, all pressures given in this document are gauge pressures.
Requirements for electronic indexes, valves and additional requirements for batteries incorporated in
the meter and any other additional functionalities are given in EN 16314:2013.
Unless otherwise stated in a particular test, the tests are carried out on meters that include additional
functionality devices intended by the manufacturer.
Clauses 1 to 13 are for design and type testing only.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
EN 437:2018, Test gases — Test pressures — Appliance categories
EN 549:2019, Rubber materials for seals and diaphragms for gas appliances and gas equipment
EN 1092-1:2018, Flanges and their joints — Circular flanges for pipes, valves, fittings and accessories, PN
designated — Part 1: Steel flanges
EN 16314:2013, Gas meters — Additional functionalities
5

---------------------- Page: 7 ----------------------
SIST EN 17526:2022
EN 17526:2021 (E)
EN ISO 228-1:2003, Pipe threads where pressure-tight joints are not made on the threads — Part 1:
Dimensions, tolerances and designation (ISO 228-1:2000)
EN ISO 1518-1:2019, Paints and varnishes — Determination of scratch resistance — Part 1: Constant-
loading method (ISO 1518-1:2019)
EN ISO 2409:2020, Paints and varnishes — Cross-cut test (ISO 2409:2020)
EN ISO 2812-1:2017, Paints and varnishes — Determination of resistance to liquids — Part 1: Immersion
in liquids other than water (ISO 2812-1:2017)
EN ISO 4628-2:2016, Paints and varnishes — Evaluation of degradation of coatings — Designation of
quantity and size of defects, and of intensity of uniform changes in appearance — Part 2: Assessment of
degree of blistering (ISO 4628-2:2016)
EN ISO 4628-3:2016, Paints and varnishes — Evaluation of degradation of coatings — Designation of
quantity and size of defects, and of intensity of uniform changes in appearance — Part 3: Assessment of
degree of rusting (ISO 4628-3:2016)
EN ISO 4892-3:2016, Plastics — Methods of exposure to laboratory light sources — Part 3: Fluorescent UV
lamps (ISO 4892-3:2016)
EN ISO 6270-1:2018, Paints and varnishes — Determination of resistance to humidity — Part 1:
Condensation (single-sided exposure) (ISO 6270-1:2017)
EN ISO 6272-1:2011, Paints and varnishes — Rapid-deformation (impact resistance) tests — Part 1:
Falling-weight test, large-area indenter (ISO 6272-1:2011)
EN ISO 9227:2017, Corrosion tests in artificial atmospheres — Salt spray tests (ISO 9227:2017)
EN ISO/CIE 11664-4:2019, Colorimetry — Part 4: CIE 1976 L*a*b* colour space (ISO/CIE 11664-4:2019)
EN 50561-1:2013, Power line communication apparatus used in low-voltage installations — Radio
disturbance characteristics - Limits and methods of measurement — Part 1: Apparatus for in-home use
EN 55032:2015, Electromagnetic compatibility of multimedia equipment — Emission Requirements
1)
EN IEC 60079-0:2018 , Explosive atmospheres — Part 0: Equipment — General requirements
(IEC 60079-0:2017)
EN 60079-10-1:2015, Explosive atmospheres — Part 10-1: Classification of areas — Explosive gas
atmospheres (IEC 60079-10-1:2015)
EN 60079-11:2012, Explosive atmospheres — Part 11: Equipment protection by intrinsic safety “i”
(IEC 60079-11:2011)
EN IEC 60079-15:2019, Explosive atmospheres — Part 15: Equipment protection by type of protection “n”
(IEC 60079-15:2017)

1) As impacted by EN IEC 60079-0:2018/AC:2020-02.
6

---------------------- Page: 8 ----------------------
SIST EN 17526:2022
EN 17526:2021 (E)
2)
EN 60529:1991 , Degrees of protection provided by enclosures (IP Code) (IEC 60529:1989)
EN 60695-11-5:2017, Fire hazard testing — Part 11-5: Test flames — Needle-flame test method -
Apparatus, confirmatory test arrangement and guidance (IEC 60695-11-5:2016)
3)
EN 60695-11-10:2013 , Fire hazard testing — Part 11-10: Test flames — 50 W horizontal and vertical
flame test methods (IEC 60695-11-10:2013)
4)
EN 60730-1:2016 , Automatic electrical controls — Part 1: General requirements (IEC 60730-1:2013 ,
modified + COR1:2014)
EN 61000-4-2:2009, Electromagnetic compatibility (EMC) — Part 4-2: Testing and measurement
techniques — Electrostatic discharge immunity test (IEC 61000-4-2:2008)
5)
EN 61000-4-3:2006 , Electromagnetic compatibility (EMC) — Part 4-3: Testing and measurement
techniques — Radiated, radio-frequency, electromagnetic field immunity test (IEC 61000-4-3:2006)
EN 61000-4-8:2010, Electromagnetic compatibility (EMC) — Part 4-8: Testing and measurement
techniques — Power frequency magnetic field immunity test (IEC 61000-4-8:2009)
EN 61000-6-1:2007, Electromagnetic compatibility (EMC) — Part 6-1: Generic standards — Immunity for
residential, commercial and light-industrial environments (IEC 61000-6-1:2005)
EN 61000-4-9:2016, Electromagnetic compatibility (EMC) — Part 4-9: Testing and measurement
techniques — Impulse magnetic field immunity test (IEC 61000-4-9:2016)
EN IEC 61000-6-2:2019, Electromagnetic compatibility (EMC) — Part 6-2: Generic standards — Immunity
standard for industrial environments
EN 62056-21:2002, Electricity metering — Data exchange for meter reading, tariff and load control — Part
21: Direct local data exchange (IEC 62056-21:2002)
ISO 834-1:1999, Fire resistance tests — Elements of building construction — Part 1: General requirements
ISO 12213-2:2006, Natural gas — Calculation of compression factor — Part 2: Calculation using molar-
composition analysis
ASTM D 1003-13, Standard Test Method for Haze and Luminous Transmittance of transparent plastics

2) As impacted by EN 60529:1991/AC:2006-12, EN 60529:1991/A1:2000, EN 60529:1991/A2:2013 and
EN 60529:1991/A2:2013/AC:2019-02.
3) As impacted by EN 60695-11-10:2013/AC:2014.
4) As impacted by EN 60730-1:2016/A1:2019.
5) As impacted by EN 61000-4-3:2006/A1:2008, EN 61000-4-3:2006/A2:2010 and EN 61000-4-3:2006/IS1:2009.
7

---------------------- Page: 9 ----------------------
SIST EN 17526:2022
EN 17526:2021 (E)
3 Terms, definitions and symbols
For the purposes of this document, the following terms, definitions and symbols apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— IEC Electropedia: available at https://www.electropedia.org/
— ISO Online browsing platform: available at https://www.iso.org/obp
3.1 Terms and definitions
3.1.1
actual flow rate
flow rate at the gas pressure and gas temperature conditions prevailing in the gas distribution line in
which the meter is fitted, at the meter inlet
3.1.2
additional functionality
functions over and above that within the meter, which can be integral to the meter, or included within a
connected device
3.1.3
additional functionality device
device that carries out additional functionalities
3.1.4
base conditions
fixed conditions to which a volume of gas is converted (e.g.  base  gas temperature 273,15 K plus 15 K
at base gas pressure of 1 013,25 mbar)
3.1.5
class 1,5 meter
accuracy achieved by a meter, which has an error of indication between −3 % and +3 % for flow rates Q,
where Q ≤ Q < Q , and an error of indication between −1,5 % and +1,5 % for flow rates Q, where
min t
Q ≤ Q ≤ Q , where Q to Q > 150 and Q to Q ≥ 10 and Q to Q is 1,2
t max max min max t r max
3.1.6
contaminants
gas borne dust, vapour and other substances that could affect the operation of the meter
3.1.7
display
device which shows information from the meter (e.g. liquid crystal that displays registers, volume or
flags)
3.1.8
distributed gas
locally available gas
8

---------------------- Page: 10 ----------------------
SIST EN 17526:2022
EN 17526:2021 (E)
3.1.9
disturbance
influence quantity having a value within the limits specified but outside the specified rated operating
conditions of the measuring instrument
Note 1 to entry: An influence quantity is a disturbance if the rated operating conditions for that influence quantity
are not specified.
3.1.10
durability
ability of an instrument to maintain its performance characteristics over a specified period of use
3.1.11
error of indication
value which shows the relationship in percentage terms of the difference between the volume indicated
by the meter and the volume which has actually flowed through the meter, to the latter value:
Note 1 to entry:
VV−
ic
ε= 100

V
c
where
V is the indicated volume;
i
V is the volume which has actually flowed through the meter.
c
3.1.12
event
condition requiring action or to log an action
3.1.13
external leak tightness
leak tightness of the gas carrying components of the gas meter with respect to the atmosphere
3.1.14
galvanic connection/interface
hard wired serial connection or pulse output from the meter
3.1.15
gas meter
instrument designed to measure, memorize and display the volume of fuel gas that has passed through it
3.1.16
gauge pressure
absolute pressure minus atmospheric pressure
3.1.17
index
current reading of the total volume passed through the meter
9

---------------------- Page: 11 ----------------------
SIST EN 17526:2022
EN 17526:2021 (E)
3.1.18
maximum operating pressure
maximum pressure at which a system can be operated continuously under normal conditions
Note 1 to entry: Normal conditions are no fault in any device or stream.
3.1.19
maximum error shift
maximum mean error shift at any of the tested flow rates
3.1.20
maximum flow rate
highest flow rate at which the gas meter provides indications that satisfy the requirements regarding
maximum permissible error (M
...

SLOVENSKI STANDARD
oSIST prEN 17526:2020
01-maj-2020
Plinomeri - Plinomer na osnovi termičnega merjenja masnega toka
Gas meters - Thermal-mass flow-meter based gas meter
Gaszähler - Thermische Massendurchflussgaszähler
Ta slovenski standard je istoveten z: prEN 17526
ICS:
91.140.40 Sistemi za oskrbo s plinom Gas supply systems
oSIST prEN 17526:2020 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------
oSIST prEN 17526:2020

---------------------- Page: 2 ----------------------
oSIST prEN 17526:2020


DRAFT
EUROPEAN STANDARD
prEN 17526
NORME EUROPÉENNE

EUROPÄISCHE NORM

May 2020
ICS 91.140.40
English Version

Gas meters - Thermal-mass flow-meter based gas meter
 Gaszähler - Thermische Massendurchflussgaszähler
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee
CEN/TC 237.

If this draft becomes a European Standard, CEN members are bound to comply with the CEN/CENELEC Internal Regulations
which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.

This draft European Standard was established by CEN 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 as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and
United Kingdom.

Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are
aware and to provide supporting documentation.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without
notice and shall not be referred to as a European Standard.


EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2020 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 17526:2020 E
worldwide for CEN national Members.

---------------------- Page: 3 ----------------------
oSIST prEN 17526:2020
prEN 17526:2020 (E)
Contents Page
European foreword . 7
1 Scope . 8
2 Normative references . 8
3 Terms, definitions and symbols . 10
3.1 Terms and definitions . 11
3.2 Symbols . 15
4 Working conditions . 17
4.1 General . 17
4.2 Base conditions . 17
4.3 Flow range . 17
4.4 Maximum working pressure . 18
4.5 Temperature range . 18
4.5.1 General . 18
4.5.2 Ambient temperature range . 18
4.5.3 Gas temperature range . 18
4.5.4 Storage temperature range . 19
4.6 Range of gases . 19
4.7 Installation orientation . 19
5 Metrological performance . 19
5.1 General . 19
5.2 Test mode comparison . 20
5.2.1 General . 20
5.2.2 Requirements . 20
5.2.3 Test . 20
5.2.4 Test mode in flow (optional) . 20
5.3 Permissible errors . 21
5.3.1 Requirements . 21
5.3.2 Test . 22
5.4 Gas-air relationship . 23
5.4.1 General . 23
5.4.2 Requirements . 23
5.4.3 Test . 23
5.5 Pressure absorption . 24
5.5.1 Requirements . 24
5.5.2 Test . 24
5.6 Metrological stability . 25
5.7 Immunity to contaminants in gas stream (dust test) . 25
5.7.1 Requirements . 25
5.7.2 Specification of contamination dust to be used in test 5.7.3 . 27
5.7.3 Test . 27
5.8 Flow disturbances . 29
5.8.1 Requirements . 29
5.8.2 Test . 29
5.9 Zero flow . 33
5.9.1 Requirements . 33
5.9.2 Test . 33
2

---------------------- Page: 4 ----------------------
oSIST prEN 17526:2020
prEN 17526:2020 (E)
5.10 Reverse flow . 34
5.10.1 Requirements . 34
5.10.2 Test . 34
5.11 Low flow registration (starting flow rate) . 34
5.11.1 Requirements . 34
5.11.2 Test . 34
5.12 Overload flow rate . 34
5.12.1 Requirements . 34
5.12.2 Test . 34
5.13 Pulsed (unsteady) flow . 35
5.13.1 General . 35
5.13.2 Requirements . 35
5.13.3 Test . 35
6 Construction and materials . 35
6.1 Mechanical interference . 35
6.1.1 Requirements . 35
6.1.2 Test . 36
6.2 Unauthorized interference . 36
6.2.1 Requirements . 36
6.2.2 Test . 36
6.3 Robustness of meter case . 36
6.3.1 Meter case. 36
6.3.2 Protection against penetration of dust and water . 36
6.3.3 External leak tightness . 37
6.3.4 Resistance to internal pressure. 37
6.3.5 Heat resistance . 38
6.3.6 Resistance to impact . 38
6.3.7 Resistance to mishandling . 41
6.4 Connections . 41
6.4.1 Orientation . 41
6.4.2 Threads and flanges for single and two pipe meters . 42
6.4.3 Strength . 45
6.5 Resistance to vibration . 46
6.5.1 Requirements . 46
6.5.2 Apparatus . 46
6.5.3 Test . 47
6.6 Corrosion protection . 48
6.6.1 General . 48
6.6.2 External corrosion . 48
6.7 Flame retardance of external surfaces . 49
6.7.1 Requirements . 49
6.7.2 Test . 49
6.8 Requirements for rubber components in the gas path . 50
6.8.1 Requirements . 50
6.8.2 Test . 50
6.9 Resistance to storage temperature range . 50
6.9.1 Requirements . 50
6.9.2 Test . 50
6.10 Resistance to toluene/iso-octane vapour . 50
6.10.1 Requirements . 50
6.10.2 Test . 50
6.11 Resistance to water vapour . 52
3

---------------------- Page: 5 ----------------------
oSIST prEN 17526:2020
prEN 17526:2020 (E)
6.11.1 Requirements . 52
6.11.2 Test . 52
6.11.3 Example of a typical apparatus . 52
6.12 Ageing . 53
6.12.1 Requirements . 53
6.12.2 Test . 53
7 Optional features . 54
7.1 Pressure measuring point . 54
7.1.1 Requirements . 54
7.1.2 Test . 54
7.2 Electrical insulating feet (optional) . 55
7.2.1 Requirements . 55
7.2.2 Test . 55
7.3 Resistance to high ambient temperatures . 55
7.3.1 Requirements . 55
7.3.2 Test . 56
7.3.3 Example of a typical resistance to high ambient temperature test apparatus . 56
7.4 Additional functionalities (if fitted) . 57
7.4.1 Requirements . 57
7.4.2 Test . 57
7.5 Use in hazardous zones . 58
7.5.1 Requirement . 58
7.5.2 Test . 58
8 Index . 58
8.1 Recording and storage . 58
8.1.1 Requirement . 58
8.1.2 Test . 58
8.2 Display . 58
8.2.1 Requirements . 58
8.2.2 Test . 59
8.3 Display functionality . 59
8.3.1 Requirements . 59
8.3.2 Test . 59
8.4 Non-volatile memory . 60
8.4.1 Requirements . 60
8.4.2 Test . 60
9 Marking . 61
9.1 All meters . 61
9.2 Two-pipe meters . 61
9.2.1 Requirements . 61
9.2.2 Test . 61
9.3 Durability and legibility of marking and labels . 62
9.3.1 Requirements . 62
9.3.2 Tests . 62
9.4 Indelibility of marking . 63
9.4.1 Requirement . 63
9.4.2 Tests . 63
10 Software . 63
10.1 Requirements . 63
10.2 Test . 63
11 Communications . 64
4

---------------------- Page: 6 ----------------------
oSIST prEN 17526:2020
prEN 17526:2020 (E)
11.1 General . 64
11.1.1 Requirements . 64
11.1.2 Test . 64
11.2 Metrological influence of radio communication function . 64
11.2.1 Requirements . 64
11.2.2 Test . 64
11.3 Test mode . 65
11.3.1 Requirements . 65
11.3.2 Test . 65
11.4 Data optical port (optional) . 65
11.5 Galvanic port (optional) . 65
11.6 Diagnostics . 65
11.6.1 Requirements .
...

Questions, Comments and Discussion

Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.