ISO 6416:2017 ハイドロメトリ — 超音波通過時間（飛行時間）法による放電の測定 | ページ 2

Foreword

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This document was prepared by Technical Committee ISO/TC 113, Hydrometry, Subcommittee SC 1, Velocity area methods.

This fourth edition cancels and replaces the third edition (ISO 6416:2004), which has been technically revised. The main changes from the previous edition are:

• the title has been changed;
• a new subclause (7.7) on wireless systems has been added;
• former subclauses 9.2 and 11.6 have been removed;
• Clause 10 on site selection has been revised;
• Annex A (Principle of measurement uncertainty) and Annex B (Performance guide for hydrometric equipment for use in technical standards) have been added.

1 Scope

This document describes the establishment and operation of an ultrasonic (transit-time) gauging station for the continuous measurement of discharge in a river, an open channel or a closed conduit. It also describes the basic principles on which the method is based, the operation and performance of associated instrumentation and procedures for commissioning.

It is limited to the “transit time of ultrasonic pulses” technique, and is not applicable to systems that make use of the “Doppler shift” or “correlation” or “level-to-flow” techniques.

This document is not applicable to measurement in rivers with ice.

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.

3 Terms and definitions

For the purposes of this document, the terms and definitions given in ISO 772 apply.

ISO and IEC maintain terminological databases for use in standardization at the following addresses:

Bibliography