ENV 14236:2002

SLOVENSKI STANDARD
01-februar-2004
8OWUD]YRþQLSOLQRPHUL]DJRVSRGLQMVWYD
Ultrasonic domestic gas meters
Ultraschall-Haushaltsgaszähler
Compteurs a gaz domestiques a ultrasons
Ta slovenski standard je istoveten z: ENV 14236:2002
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.

EUROPEAN PRESTANDARD
ENV 14236
PRÉNORME EUROPÉENNE
EUROPÄISCHE VORNORM
July 2002
ICS 91.140.40
English version
Ultrasonic domestic gas meters
This European Prestandard (ENV) was approved by CEN on 25 March 2002 as a prospective standard for provisional application.
The period of validity of this ENV is limited initially to three years. After two years the members of CEN will be requested to submit their
comments, particularly on the question whether the ENV can be converted into a European Standard.
CEN members are required to announce the existence of this ENV in the same way as for an EN and to make the ENV available promptly
at national level in an appropriate form. It is permissible to keep conflicting national standards in force (in parallel to the ENV) until the final
decision about the possible conversion of the ENV into an EN is reached.
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 STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36  B-1050 Brussels
© 2002 CEN All rights of exploitation in any form and by any means reserved Ref. No. ENV 14236:2002 E
worldwide for CEN national Members.

Contents
page
Foreword .6
1 Scope.7
2 Normative references.7
3 Terms, definitions and symbols .9
3.1 Terms and definitions.9
3.2 Symbols .12
4 Normal operating conditions .12
4.1 Flow range .12
4.2 Maximum working pressure.13
4.3 Temperature range.13
4.4 Range of gases.13
4.4.1 General .13
4.4.2 Test gases.13
4.4.3 Test gas properties .14
5 Metrological performance .15
5.1 General .15
5.2 Mode comparison.15
5.2.1 General .15
5.2.2 Requirements .16
5.2.3 Test .16
5.3 Permissible errors.16
5.3.1 Requirements .16
5.3.2 Test .16
5.4 Gas — air relationship .17
5.4.1 General .17
5.4.2 Requirements .17
5.4.3 Test .19
5.5 Pressure absorption .19
5.5.1 Requirements .19
5.5.2 Test .19
5.6 Metrological stability.19
5.6.1 Requirements .19
5.6.2 Test .19
5.7 Immunity to contaminants in gas stream .19
5.7.1 Requirements .19
5.7.2 Test .19
5.7.3 Specification of contamination dust .21
5.8 Installation effects.21
5.8.1 Requirements .21
5.8.2 Test .21
5.9 Zero flow .21
5.9.1 Requirements .21
5.9.2 Test .22
5.10 Reverse flow .22
5.10.1 Requirements .22
5.10.2 Test .22
5.11 Low flow registration .22
5.11.1 Requirement .22
5.11.2 Test .22
5.12 High flow registration .22
5.12.1 Requirement .22
5.12.2 Test .22
5.13 Pulsed (unsteady) flow .22
5.13.1 General .22
5.13.2 Requirements .23
5.13.3 Test .23
5.14 Temperature sensitivity.24
5.14.1 Requirements .24
5.14.2 Test .24
6 Construction and materials.24
6.1 General .24
6.2 Robustness of meter case .24
6.2.1 General .24
6.2.2 Protection against penetration of dust and water .24
6.2.3 Resistance to internal pressure.25
6.2.4 External leak tightness .25
6.2.5 Heat resistance.25
6.2.6 Connections.25
6.2.7 Resistance to vibration.29
6.2.8 Resistance to impact .31
6.2.9 Resistance to mishandling.33
6.3 Corrosion protection.34
6.3.1 General .34
6.3.2 Protection against external corrosion for material which is not corrosion resistant.34
6.3.3 Protection against external corrosion for corrosion resistant material.36
6.3.4 Protection against internal corrosion for material which is not corrosion resistant.37
6.3.5 Protection against internal corrosion for corrosion resistant material.39
6.4 Casework decorative finish.39
6.4.1 Scratch test.39
6.4.2 Humidity.40
6.5 Ageing of non-metallic casework.40
6.5.1 Requirements .40
6.5.2 Test .40
6.6 Ageing of external surfaces of the meter, including index windows and adhesion
of the index window.40
6.6.1 Requirements .40
6.6.2 Test .41
6.7 Protection against solar radiation.41
6.7.1 Requirements .41
6.7.2 Test .41
6.8 Resistance to external relative humidity .41
6.8.1 Requirements .41
6.8.2 Test .41
6.9 Flame retardance of external surfaces .42
6.9.1 Requirements .42
6.9.2 Test .42
6.10 Resistance to storage temperature range .42
6.10.1 Requirement .42
6.10.2 Test .42
6.11 Resistance to the effects of toluene/iso-octane vapour .42
6.11.1 Requirements .42
6.11.2 Test .43
6.12 Resistance to water vapour .46
6.12.1 Requirements .46
6.12.2 Test .46
6.13 Ageing .48
6.13.1 Requirements .48
6.13.2 Test .48
7 Optional features.48
7.1 Pressure measuring point.48
7.1.1 Requirements .48
7.1.2 Test .48
7.2 Resistance to high ambient temperature.49
7.2.1 Requirements .49
7.2.2 Test .49
7.2.3 Meter fitted with a thermal shut-off valve .51
7.3 Meters with temperature conversion .51
7.4 Ancillary devices.51
7.5 Use in hazardous zones .51
8 Index .51
8.1 Recording and storage .51
8.1.1 Requirement .51
8.1.2 Test .51
8.2 Display.51
8.2.1 Requirement .51
8.2.2 Test .52
8.3 Segmental display.52
8.3.1 Requirements .52
8.3.2 Test .52
8.4 Non-volatile memory.52
8.4.1 Requirements .52
8.4.2 Test .52
9 Marking.53
9.1 All meters .53
9.2 Two-pipe meters.53
9.3 Durability and legibility of marking .53
9.3.1 Requirements .53
9.3.2 Ultraviolet exposure test .54
9.3.3 Indelibility test .54
10 Software .54
10.1 Requirements .54
10.2 Test .54
11 Communications .54
11.1 General .54
11.2 Character transmission .55
11.3 Communications protocol.55
11.3.1 Wakeup.55
11.3.2 Sign-off.57
11.3.3 Security .57
11.3.4 Time-outs .57
11.4 Data.57
11.4.1 General .57
11.4.2 Data read-out mode.57
11.4.3 Data identifiers .57
11.4.4 Data set structure.58
11.5 Test-mode .58
11.5.1 General .58
11.5.2 Test-mode commands .58
11.5.3 Response of meter to test commands.59
11.6 Optical port .60
11.7 Galvanic port (optional).60
11.8 Diagnostics .60
11.8.1 General .60
11.8.2 Displayed flags.61
12 Battery .62
12.1 General .62
12.2 Voltage interruptions .62
12.2.1 Requirements .62
12.2.2 Test .62
12.3 Minimum operating voltage .62
12.3.1 Requirements .62
12.3.2 Test .62
12.4 Battery life.62
13 Immunity to electromagnetic disturbances.63
13.1 General .63
13.2 Electrostatic discharge.63
13.2.1 Requirements .63
13.2.2 Test .63
13.3 Radio frequency electromagnetic field.63
13.3.1 Requirements .63
13.3.2 Test .63
13.4 Electromagnetic induction (power frequency).64
13.4.1 Requirements .64
13.4.2 Test .64
13.5 Electromagnetic induction (pulsed field) .64
13.5.1 Requirements .64
13.5.2 Test .65
13.6 Radio interference suppression .65
13.6.1 Requirements .65
13.6.2 Test .65
14 Ultrasonic (acoustic) noise interference.65
14.1 Requirements .65
14.2 Test .65
14.2.1 Test sequence .65
14.2.2 White noise test.65
14.2.3 Scanning frequency test .66
15 Meters supplied for testing .66
Annex A (normative)  Production requirements for gas meters .69
A.1 Specification.69
A.2 Technical requirements.69
A.3 Certificates of conformity.69
(normative)
Annex B Meters with gas temperature conversion devices.71
B.1 Scope.71
B.2 Metrological performance .71
B.2.1 Errors of indication .71
Gas and ambient temperature .71
Gas and ambient temperature .71
B.2.2 Gas air relationship.74
Gas and ambient temperature .74
Gas and ambient temperature .74
B.2.3 Temperature sensitivity.74
Bibliography .75
Foreword
This document ENV 14236:2002 has been prepared by Technical Committee CEN/TC 237 "Gas
meters", the secretariat of which is held by BSI.
The metrological aspects of this Pre-standard may be subject to amendments to bring it into line with
the proposed Measuring Instruments Directive.
In this standard the annexes A and B are normative.
This standard includes a Bibliography.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to announce this European Prestandard: 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 Scope
This European Prestandard specifies requirements and tests for the construction, performance and
safety of battery powered ultrasonic gas meters (hereinafter referred to as meters), having co-axial
single pipe, or two pipe connections, used to measure volumes of distributed fuel gases of the first
and/or second and/or third family, as given in EN 437, at maximum working pressures of up to
1)
0,5 bar and maximum actual flow rates of up to 10 m³/h over a minimum ambient and gas
temperature range of -10 °C to +40 °C, for domestic applications. This prestandard applies to meters
where the measuring element and the register(s) are enclosed in the same case.
Unless otherwise stated, all pressures given in this document are gauge pressures.
Clauses 1 to 15 and annex B are for design and type testing only.
NOTE See annex A for production requirements.
2 Normative references
This European Prestandard incorporates by dated or undated reference provisions from other
publications. These normative references are cited at the appropriate places in the text, and the
publications are listed hereafter. For dated references, subsequent amendments to or revisions of any
of these publications apply to this European Prestandard only when incorporated in it by amendment
or revision. For undated references the latest edition of the publication referred to applies (including
amendments).
EN 437, Test gases — Test pressures — Appliance categories.
EN 50014, Electrical apparatus for potentially explosive atmospheres — General requirements.
EN 50020, Electrical apparatus for potentially explosive atmospheres — Intrinsic safety ‘i’.
EN 50021, Electrical apparatus for potentially explosive atmospheres —Type of protection ‘n’.
EN 50082-1, Electromagnetic compatibility — Generic immunity standard — Part 1: Residential,
commercial and light industry.
EN 55022, Information technology equipment – Radio disturbance characteristics – Limits and
methods of measurement (CISPR 22:1997, modified).
EN 60068-2-5, Environmental testing – Part 2: Tests – Test Sa: Simulated solar radiation at ground
level (IEC 60068-2-5:1975).
EN 60068-2-30, Environmental testing – Part 2: Tests – Test Db and guidance : Damp heat, cyclic (12
+ 12 hour cycle) (IEC 60068-2-30:1980 + A1:1985).
EN 60079-10, Electrical apparatus for explosive gas atmospheres — Part 10: Classification of
hazardous areas (IEC 60079-10:1995).
EN 60086-1, Primary batteries — Part 1: General (IEC 60086-1:2000).
EN 60086-4, Primary batteries — Part 4: Safety standard for lithium batteries (IEC 60086-4:2000).

1) 1 bar = 1 000 mbar = 10 Pa.
EN 60529, Degrees of protection provided by enclosure (IP code) (IEC 60529:1989).
EN 60695-2, Fire hazard testing — Part 2: Test methods.
EN 60707, Flammability of solid non-metallic materials when exposed to flame sources — List of test
methods (IEC 60707:1999).
EN 60730-1:2000, Automatic electrical controls for household and similar use — Part 1: General
requirements (IEC 60730-1:1999, modified).
EN 61000-4-2, Electromagnetic compatibility (EMC) — Part 4: Testing and measurement
techniques — Section 2: Electrostatic discharge immunity test — Basic EMC publication (IEC 61000-
4-2:1995).
EN 61000-4-3, Electromagnetic compatibility (EMC) — Part 4: Testing and measurement
techniques — Section 3: Radiated, radio frequency electromagnetic field immunity test — (IEC 61000-
4-3:1995, modified).
EN 61000-4-8, Electromagnetic compatibility (EMC) — Part 4: Testing and measurement
techniques — Section 8: Power frequency magnetic field immunity test — Basic EMC publication (IEC
61000-4-8:1993).
EN 61000-4-9, Electromagnetic compatibility (EMC) — Part 4: Testing and measurement
techniques — Section 9: Pulse magnetic field immunity test — Basic EMC publication (IEC 61000-4-
9:1993).
EN 61000-6-2, Electromagnetic compatibility (EMC) – Part 6-2: Generic standards – Immunity for
industrial environments (IEC 61006-2-2:1999).
EN 61107: 1996, Data exchange for meter reading, tariff and load control — Direct local data
exchange (IEC 61107:1996).
EN ISO 2409, Paints and varnishes — Cross-cut test (ISO 2409:1992).
EN ISO 2812-1:1994, Paints and varnishes — Determination of resistance to liquids — Part 1:
General methods (ISO 2812-1:1993).
EN ISO 6270-1, Paints and varnishes — Determination of resistance to humidity — Part 1: Continuous
condensation (ISO 6270-1:1998).
EN ISO 6272, Paints and varnishes — Falling-weight test (ISO 6272:1993).
ISO 228-1, Pipe threads where pressure-tight joints are not made on the threads — Part 1: Dimensions,
tolerances and designation.
ISO 834-1, Fire resistance tests — Elements of building construction – Part 1: General requirements.
ISO 1518, Paints and varnishes — Scratch test.
ISO 4628-2, Paints and varnishes — Evaluation of degradation of paint coatings — Designation of
intensity, quantity and size of common types of defect — Part 2: Designation of degree of blistering.
ISO 4628-3:1982, Paints and varnishes — Evaluation of degradation of paint coatings — Designation
of intensity, quantity and size of common types of defect — Part 3: Designation of degree of rusting.
ISO/TR 5168, Measurement of fluid flow — Evaluation of uncertainties.
ASTM D 471, Test method for rubber property — Effect of liquids.
3 Terms, definitions and symbols
3.1 Terms and definitions
For the purposes of this European Prestandard, the following terms and definitions apply.
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
base conditions
fixed conditions to which a volume of gas is converted. (i.e. base gas temperature 15 °C, base gas
pressure 1 013,25 mbar)
3.1.3
contaminants
gas borne dust, vapour, and other substances that could affect the operation of the meter
3.1.4
communications port
galvanic or optical serial data port
3.1.5
display
device (e.g. liquid crystal display) which shows the contents of a memory (e.g. registered volume or
flags)
3.1.6
distributed gas
gas locally available
3.1.7
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
volume:
Vi-Vc
˛= ⋅100
Vc
where
3 3
V is the indicated volume in cubic metres (m ) and V is the volume in cubic metres (m ) that
i c
has actually flowed through the meter.
3.1.8
external leak tightness
leak tightness of the gas carrying components of the gas meter with respect to the atmosphere
3.1.9
flag
single alphabetic character on the index giving a visual signal of significant events and/or change(s) in
the operation of the meter
3.1.10
galvanic connection/interface
hard wired serial connection or pulse output from the meter
3.1.11
index
all that which is viewed through the index window, including the display
3.1.12
index window(s)
area(s) of transparent material through which the index can be read
3.1.13
maximum error shift
maximum mean error shift at any of the tested flow rates
3.1.14
maximum working pressure
upper limit of the working pressure for which the meter has been designed, as declared by the
manufacturer and marked on the index or the data plate
3.1.15
mean error
arithmetic mean of consecutive errors of indication at a flow rate
3.1.16
measuring element
part of the meter which produces an electrical signal proportional to the gas flow rate
3.1.17
memory
element which stores digital information
3.1.18
meter case
meter complete with any meter cover
3.1.19
meter cover
rigid enclosure on the front of the meter made either wholly of transparent material, or of opaque
material provided with index window(s)
3.1.20
normal conditions of operation
conditions referring to the meter operating:
 at a pressure up to the maximum working pressure (with or without a flow of gas);
 within the range of flow rates;
 within the ambient temperature range;
 with the distributed gas.
3.1.21
operating mode
method (sample frequency and timing) of obtaining volume flow measurements
3.1.22
optical port
serial data port using an infra-red transmitter and receiver
3.1.23
pressure absorption
difference between the pressure measured at the inlet and outlet connections of the meter whilst the
meter is operating
3.1.24
pressure measuring point
permanent fitting on the meter outlet enabling a direct measurement of the outlet pressure to be
obtained
3.1.25
range of mean errors
difference between the minimum and maximum mean errors over a specified flow range
3.1.26
regression line
straight line, generated using a statistical method, to give a graphical representation of a set of results
3.1.27
register
electronic device comprising both memory and display, which stores and displays information
3.1.28
segment
individual Part of a display which is able to show a portion of a character
3.1.29
starting flow rate
lowest flow rate at which the meter is able to indicate a volume of gas passed
3.1.30
temperature conversion device
device which converts the measured volume to a corresponding volume at base gas temperature
3.1.31
thermal cut-off valve
heat sensitive valve used to cut off the flow of gas to the meter if the ambient temperature rises above
a predetermined level for a specified time
3.1.32
ultrasonic gas meter
gas meter that uses ultrasound to determine the volume of gas passing through it
3.1.33
ultrasonic transducer
device used to generate and detect the ultrasound signals within the meter
3.1.34
working pressure
difference between the pressure of the gas at the inlet of the meter and the atmospheric pressure
3.2 Symbols
3.2.1
Q
min
minimum flow rate, specified in cubic metres per hour (m /h) for which the meter has been designed
3.2.2
Q
max
maximum flow rate, specified in cubic metres per hour (m /h) for which the meter has been designed
3.2.3
Q
t
transitional flow rate, occurring between the maximum and minimum flow rates at which the flow rate
range is divided into two zones, the ‘upper zone’ and the ‘lower zone’. Each zone has a characteristic
maximum permissible error
3.2.4
t
m
gas and ambient temperature range of the meter
3.2.5
D
outside diameter of the pipe in millimetres (mm)
3.2.6
MPE
maximum permissible error, in percent (%)
3.2.7
g
-2
acceleration due to gravity, in metres per square second (m⋅s )
4 Normal operating conditions
4.1 Flow range
The values of maximum flow rates and those corresponding values of the upper limits of the minimum
flow rates shall be those given in Table 1.
Table 1 — Flow range
Q Upper limits of Q
max min
3 3
m /h m /h
10,016
1,6 0,016
2,5 0,016
40,025
60,040
10 0,060
Q shall not exceed 0,1 Q
t max
4.2 Maximum working pressure
The manufacturer shall declare the maximum working pressure of the meter and this pressure shall
be marked on the index or data plate of the meter. This pressure shall not exceed 0,5 bar.
4.3 Temperature range
Unless otherwise stated, all temperatures given in this document are to ± 1 °C.
All meters shall be capable of meeting the requirements for a minimum ambient temperature range
and a minimum gas temperature range of -10 °C to +40 °C (see 5.14) and minimum storage
temperature range of -20 °C to +60 °C.
If the manufacturer declares a wider ambient and gas temperature range and/or a wider storage
temperature range, the meter shall be capable of meeting the requirements over this declared wider
range.
If the manufacturer declares th
...