SIST EN 17526:2022/oprA1:2024

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

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 exceeding 160 m3/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.

Gaszähler - Thermische Massendurchflussgaszähler

Compteurs de gaz - Compteur de gaz basé sur un débitmètre massique par effet thermique

Plinomeri - Plinomer na osnovi termičnega merjenja masnega toka - Dopolnilo A1

General Information

• Status: Not Published
• Public Enquiry End Date: 01-Nov-2024
• ICS: 91.140.40 - Gas supply systems
• Technical Committee: DPL - Gas supply
• Current Stage: 98 - Abandoned project (Adopted Project)
• Start Date: 09-May-2025
• Due Date: 14-May-2025
• Completion Date: 12-May-2025
• Directive: 2014/32/EU - Directive 2014/32/EU of the European Parliament and of the Council of 26 February 2014 on the harmonisation of the laws of the Member States relating to the making available on the market of measuring instruments
• Mandate: M/541 - [C(2015)8558] Standardization request in support of the implementation of Directive 2014/32/EU on measuring instruments
• Ref Project: EN 17526:2021/prA1 - Gas meter - Thermal-mass flow-meter based gas meter

Relations

• Consolidated By: SIST EN 17526:2022+A1:2025 - Gas meter - Thermal-mass flow-meter based gas meter
• Effective Date: 01-Jul-2025
• Revises: SIST EN 17526:2022 - Gas meters - Thermal-mass flow-meter based gas meter
• Effective Date: 01-Oct-2024

Overview

The SIST EN 17526:2022/oprA1:2024 standard, issued by CEN, defines rigorous requirements and testing protocols for battery-powered thermal-mass flow meter gas meters. These class 1.5 meters utilize the capillary thermal-mass flow sensor principle to measure volumes of fuel gases belonging to the 2nd and/or 3rd family as classified in EN 437:2018. Thermal mass flow meters operate based on heat transfer principles and provide gas volume measurements corrected to base conditions of temperature and pressure, ensuring high accuracy and reliability.

This amendment A1, supplementing EN 17526:2021, introduces updated requirements and testing procedures especially focused on label durability, weathering resistance, and suitability for both closed and open location installations. The standard addresses environmental considerations such as vibration, shock, electromagnetic disturbances, and humidity conditions applicable to residential, commercial, and light industrial settings.

Key Topics

• Thermal-mass flow measurement principle: Heat transfer technology for accurate gas flowrate measurement at base reference conditions.
• Scope of application: Suitable for meter installations with maximum working pressure of up to 0.5 bar and flowrates not exceeding 160 m³/h within ambient temperatures from −10 °C to +40 °C.
• Construction and performance: Specifies design and type testing clauses ensuring safety, metrological performance, and durability.
• Label adhesion and durability: New stringent tests for metrology label adhesion, visual legibility, and resistance to UV exposure and weathering in both open and closed locations.
• Environmental suitability: Meters tested for use in closed protected environments as well as open outdoor locations exposed to weather, temperature fluctuations, and electromagnetic interference.
• Testing protocols: Detailed exposure cycles to ultraviolet radiation, immersion in ionized water, artificial weathering per EN ISO 4892-3:2016, and adhesion force measurement methods.

Applications

• Residential gas metering: Accurate volume measurement for fuel gases in homes, ensuring reliable billing and consumption monitoring.
• Commercial and light industrial use: Suitable for installations requiring robust, maintenance-light gas flow meters able to withstand moderate environmental challenges.
• Utility and energy providers: Use in gas supply systems for real-time flow monitoring with battery-powered devices that meet European safety and performance standards.
• Outdoor and indoor installations: Compliance with environmental durability criteria facilitates flexible site placement including unprotected outdoor setups as specified by manufacturers.
• Integration with electronic devices: Compatibility with indexes, valves, batteries, and additional functionalities governed by related standards promotes enhanced metering system solutions.

Related Standards

• EN 437:2018 – Classification of fuel gases relevant for defining gas families measured by these meters.
• ISO 14511 – Defines the thermal mass flow measurement principle applied in gas meter technology.
• EN 16314:2013 – Covers additional requirements for electronic indexes, valves, battery incorporation, and other functionalities within gas meters.
• EN ISO 4892-3:2016 – Provides guidelines for artificial weathering tests applicable in evaluating meter label endurance under UV exposure.
• EN ISO/CIE 11664-4:2019 – Specifies color measurement standards ensuring label legibility after environmental tests.
• ASTM D 1003-13 – Sets requirements for haze and light transmission properties vital for meter window visibility.

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SIST EN 17526:2022/oprA1:2024 ensures that thermal-mass flow-meter based gas meters meet stringent quality, safety, and environmental durability standards. Its comprehensive testing framework and clear guidelines facilitate manufacturing of reliable, accurate, and robust gas meters suitable for diverse installations while maintaining compliance with European regulations. This standard is essential for manufacturers, testing laboratories, and utility companies focused on advanced gas metering technologies.

Standards Content (Sample)

SLOVENSKI STANDARD
01-oktober-2024
Plinomeri - Plinomer na osnovi termičnega merjenja masnega toka - Dopolnilo A1
Gas meter - Thermal-mass flow-meter based gas meter
Gaszähler - Thermische Massendurchflussgaszähler
Compteurs de gaz - Compteur de gaz basé sur un débitmètre massique par effet
thermique
Ta slovenski standard je istoveten z: EN 17526:2021/prA1
ICS:
91.140.40 Sistemi za oskrbo s plinom Gas supply systems
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

DRAFT
EUROPEAN STANDARD
EN 17526:2021
NORME EUROPÉENNE
EUROPÄISCHE NORM
prA1
August 2024
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 draft amendment is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee CEN/TC 237.

This draft amendment A1, if approved, will modify the European Standard EN 17526:2021. If this draft becomes an amendment,
CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for inclusion of
this amendment into the relevant national standard without any alteration.

This draft amendment 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, Türkiye 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
© 2024 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 17526:2021/prA1:2024 E
worldwide for CEN national Members.

Contents Page
European foreword . 3
1 Modification to subclause 9.3.1, “Requirements” . 4
2 Modification to subclause 9.3.2, “Tests” . 4
3 Addition of subclause 9.3.3, “Open location test” . 4
European foreword
This document (EN 17526:2021/prA1:2024) has been prepared by Technical Committee CEN/TC 237
“Gas meters”, the secretariat of which is held by BSI.
This document is currently submitted to the CEN Enquiry.
This document has been prepared under a standardization request addressed to CEN by
...