EN ISO 6416:2005

SLOVENSKI STANDARD
01-november-2005
+LGURPHWULMD±0HUMHQMHSUHWRND]XOWUD]YRþQRDNXVWLþQRPHWRGR,62
Hydrometry - Measurement of discharge by the ultrasonic (acoustic) method (ISO
6416:2004)
Hydrometrie - Messung des Abflusses mit dem Ultraschallverfahren (akustisches
Verfahren) (ISO 6416:2004)
Hydrométrie - Mesure du débit a l'aide de la méthode ultrasonique (acoustique) (ISO
6416:2004)
Ta slovenski standard je istoveten z: EN ISO 6416:2005
ICS:
17.120.20 Pretok v odprtih kanalih Flow in open channels
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN ISO 6416
NORME EUROPÉENNE
EUROPÄISCHE NORM
August 2005
ICS 17.120.20
English Version
Hydrometry - Measurement of discharge by the ultrasonic
(acoustic) method (ISO 6416:2004)
Hydrométrie - Mesure du débit à l'aide de la méthode Hydrometrie - Messung des Abflusses mit dem
ultrasonique (acoustique) (ISO 6416:2004) Ultraschallverfahren (akustisches Verfahren) (ISO
6416:2004)
This European Standard was approved by CEN on 11 July 2005.
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 Central Secretariat 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 Central Secretariat has the same status as the official
versions.
CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,
Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia,
Slovenia, Spain, Sweden, Switzerland and United Kingdom.
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© 2005 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 6416:2005: E
worldwide for CEN national Members.

Foreword
The text of ISO 6416:2004 has been prepared by Technical Committee ISO/TC 113 "Hydrometric
determinations" of the International Organization for Standardization (ISO) and has been taken
over as EN ISO 6416:2005 by Technical Committee CEN/TC 318 "Hydrometry", 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 February 2006, and conflicting national
standards shall be withdrawn at the latest by February 2006.

According to the CEN/CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Cyprus,
Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,
Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.

Endorsement notice
The text of ISO 6416:2004 has been approved by CEN as EN ISO 6416:2005 without any
modifications.
INTERNATIONAL ISO
STANDARD 6416
Third edition
2004-07-01
Hydrometry — Measurement of discharge
by the ultrasonic (acoustic) method
Hydrométrie — Mesure du débit à l'aide de la méthode ultrasonique
(acoustique)
Reference number
ISO 6416:2004(E)
©
ISO 2004
ISO 6416:2004(E)
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ISO 6416:2004(E)
Contents Page
Foreword. v
1 Scope. 1
2 Normative references . 1
3 Terms and definitions. 1
4 Applications. 1
4.1 Open channels . 1
4.2 Multiple channels . 2
4.3 Closed conduits . 2
5 Method of measurement. 3
5.1 Discharge. 3
5.2 Calculation of discharge from the transit-time measurement. 3
6 Flow velocity determination by the ultrasonic (transit time) method. 3
6.1 Principle . 3
6.2 Sound propagation in water. 6
7 Gauge configuration . 10
7.1 General. 10
7.2 Single-path systems . 11
7.3 Multi-path systems. 12
7.4 Crossed path systems. 12
7.5 Reflected-path systems. 14
7.6 Systems using transponders. 15
7.7 Systems using divided cross-sections. 16
7.8 Sloping paths . 17
8 Calculation of discharge . 17
8.1 Single-path systems . 17
8.2 Multi-path systems. 17
8.3 Systems with transducers in the channel . 21
9 System calibration . 21
9.1 General. 21
9.2 Single-path systems . 22
10 Site selection . 24
10.1 Practical constraints. 24
10.2 Physical constraints of the measurement site. 25
10.3 Physical constraints which are distant from the measurement site . 25
11 Site survey — Before design and construction. 26
11.1 General. 26
11.2 Visual survey . 26
11.3 Survey of the cross-section. 27
11.4 Survey of velocity distribution . 27
11.5 Survey of signal propagation. 28
11.6 Other survey activities. 28
12 Operational measurement requirements. 28
12.1 General. 28
12.2 Basic components of flow determination. 29
12.3 Water velocity determination. 29
12.4 Determination of water stage or depth . 29
ISO 6416:2004(E)
12.5 Channel width.30
13 Gauging station equipment.30
13.1 General .30
13.2 Design and construction of equipment.31
13.3 Reflectors .32
13.4 Civil engineering works .35
13.5 Signal timing and processing .35
13.6 System self-checking.37
13.7 Site-specific data (or site parameters) .38
13.8 Clock and calendar.38
13.9 System performance criteria.38
13.10 System output.40
13.11 Installation.40
13.12 Commissioning.41
13.13 Operati
...