National Standard for Flow and Volume of Water Passed

National Standard for Flow and Volume of Water Passed

The National Standard for Flow and Volume of Water Passed consists of a set of devices designed to maintain and transfer the units of liquid volume, mass flow, volumetric flow, and mass flow rate of liquids. It belongs to the group of technical quantity standards.

A characteristic feature of volume and mass flow quantities is that they are among the most widely used measuring instruments in commercial transactions.

The field of water flow measurement encompasses various measuring principles applied to water at different temperatures and over a wide range of flow rates. It includes:

• Measuring instruments and systems used in long-distance water pipelines and district heating systems, with flow rates in the range of hundreds to thousands of cubic meters per hour (m³/h).
• Industrial water supply networks, building heating systems, and dispensing stations for liquid beverages, with flow rates ranging from tens to hundreds of cubic meters per hour (m³/h).
• Residential water meters and heat meters installed in apartments, measuring flow rates in the range of tens of deciliters per hour (dm³/h) to cubic meters per hour (m³/h).

Scope and Parameters of the National Standard

The scope and parameters of the National Standard are selected to cover the most commonly used flow ranges and measured media temperatures.

The National Standard for Flow and Volume of Water Passed is a gravimetric reference system with:

• Two measuring lines,
• Three mass measurement systems,
• Six flow measurement branches,
• A flow source based on an open overflow tank principle.

The design and spatial arrangement of the National Standard for Flow and Volume of Water Passed allow for testing of measuring instruments based on various measurement principles and the use of different measurement methods while ensuring compliance with the integrated quality system (STN EN ISO/IEC 17025 and STN ISO 9001).

From a testing methodology perspective, the flying start method and the fixed start method can be used. The system supports the connection of measuring instruments with a mechanical counter or a passive pulse output.

 

Documents for download

• Osvedčenie (certifikát) (pdf, 1.3 MB)