ISO 16399:2014

INTERNATIONAL ISO
STANDARD 16399
First edition
2014-05-01
Meters for irrigation water
Compteurs pour l’eau d’irrigation
Reference number
©
ISO 2014
© ISO 2014
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ii © ISO 2014 – All rights reserved

Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Metrological characteristics . 5
4.1 Maximum permissible error (MPE) . 5
4.2 Metrological characteristics . 5
5 Technical characteristics . 6
5.1 General specifications . 6
5.2 Rated operating conditions . 7
5.3 Materials . 7
5.4 Indicating device . 7
5.5 Reverse flow . 8
5.6 Sealing and security . 8
5.7 Other devices . 9
6 Metrological requirements . 9
6.1 Indicating error . 9
6.2 Internal pressure . 9
6.3 Flow profile sensitivity classes . 9
6.4 Pressure loss .10
7 Performance tests .11
7.1 General conditions for the tests .11
7.2 Static pressure test .12
7.3 Determination of errors .12
7.4 Pressure loss test .14
7.5 Flow disturbance tests .14
7.6 Reverse flow test .17
7.7 Endurance tests .18
8 Tests related to the influence quantities and perturbations .24
9 Marking .24
Annex A (informative) Pulse input solutions .26
Annex B (normative) Flow disturbers .33
Bibliography .47
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation on the meaning of ISO specific terms and expressions related to conformity
assessment, as well as information about ISO’s adherence to the WTO principles in the Technical Barriers
to Trade (TBT) see the following URL: Foreword - Supplementary information
The committee responsible for this document is ISO/TC 23, Tractors and machinery for agriculture and
forestry, Subcommittee SC 18, Irrigation and drainage equipment and systems.
iv © ISO 2014 – All rights reserved

INTERNATIONAL STANDARD ISO 16399:2014(E)
Meters for irrigation water
1 Scope
This International Standard applies to water meters intended for irrigation use (herein after referred to
as water meters), regardless of the water quality used for this purpose, and specifies the requirements
and certification procedures for water meters, irrespective of the design technologies used to meter the
actual volume of cold water or heated water flowing through a fully charged closed conduit. These water
meters incorporate devices which indicate the integrated volume.
This International Standard also applies to water meters based on electrical or electronic principles
and to water meters based on mechanical principles, incorporating electronic devices used to meter
the actual volume flow of cold water. It provides metrological requirements for electronic ancillary
devices when they are subject to metrological control. As a rule, the ancillary devices are optional.
However national or international regulations make some ancillary devices mandatory in relation to
the utilization of the water meter.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.
ISO 4064-1:2005, Measurement of water flow in fully charged closed conduits — Meters for cold potable
water and hot water — Part 1: Specifications
ISO 4064-2:2005, Measurement of water flow in fully charged closed conduits — Meters for cold potable
water and hot water — Part 2: Installation requirements
ISO 9644, Agricultural irrigation equipment — Pressure losses in irrigation valves — Test method
ISO 286-2, Geometrical product specifications (GPS) — ISO code system for tolerances on linear sizes —
Part 2: Tables of standard tolerance classes and limit deviations for holes and shafts
ISO 228-1, Pipe threads where pressure-tight joints are not made on the threads — Part 1: Dimensions,
tolerances and designation
ISO/IEC Guide 98-3, Uncertainty of measurement — Part 3: Guide to the expression of uncertainty in
measurement (GUM:1995)
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
water meter
instrument intended to measure continuously, store, and display the volume of water passing through
the measurement transducer at metering conditions
Note 1 to entry: A water meter includes at least a measurement transducer, a calculator (including adjustment or
correction devices, if present), and an indicating device. These three devices may be in different housings.
[SOURCE: OIML R49-1:2006, 2.1.1, modified — The second note is not included here.]
3.2
indicating device
part of the meter that provides an indication corresponding to the volume of water passing through the
meter
3.3
actual volume
V
a
total volume of water passing through the meter
Note 1 to entry: The actual volume is calculated from a reference volume as determined by a suitable measurement
standard taking into account differences in metering conditions, as appropriate.
[SOURCE: OIML R49-1:2006, 2.2.1, modified — The phrases “disregarding the time taken” and “This is
the measurand” have been removed from the definition.]
3.4
indicated volume
V
i
volume of water indicated by the meter, corresponding to the actual volume
[SOURCE: OIML R49-1:2006]
3.5
flow rate
Q
volume of water flowing through a device per unit time
3.6
minimum flow rate
Q
lowest flow rate at which the meter is required to operate within the maximum permissible error
3.7
transitional flow rate
Q
flow rate between the permanent flow rate ≥ 100 ≥ 10 and the minimum flow rate ≥5 that divides the
flow rate range into two zones, the “upper zone” and the “lower zone”, each characterized by its own
maximum permissible error
3.8
permanent flow rate
Q
highest flow rate under normal service conditions at which the meter is required to operate in a
satisfactory manner within the maximum permissible error
3.9
overload flow rate
Q
highest flow rate at which the water meter is designed to operate for a short period of time within its
maximum permissible error, whilst maintaining its metrological performance when it is subsequently
operated under normal service conditions
3.10
test flow rate
mean flow rate during a test, calculated from the indications of a calibrated reference device
2 © ISO 2014 – All rights reserved

3.11
error
measured quantity value minus a reference quantity value
VV−
ia
×100(%)
V
a
3.12
maximum permissible error
MPE
extreme value of error permitted by this International Standard
3.13
working pressure
P
w
average water pressure in the pipe measured upstream of the meter
3.14
durability
ability of a meter to maintain its performance characteristics over a per
...