EN IEC 61207-2-2019 pdf download.Expression of performance of gas analyzers – Part 2: Measuring oxygen in gas utilizing high-temperature electrochemical sensors (IEC 61207-2:2019).
This part of IEC 61 207 applies to all aspects of analyzers using high-temperature electrochemical sensors for the measurement of oxygen in gas.
It applies to in-situ and extractive analyzers and to analyzers installed indoors and outdoors.
The object of this part is:
– to specify the terminology and definitions related to the functional performance of gas analyzers, utilizing a high-temperature electrochemical sensor, for the continuous measurement of oxygen concentration in a sample of gas;
– to unify methods used in making and verifying statements on the functional performance of such analyzers;
– to specify what tests are performed to determine the functional performance and how such tests are carried out;
– to provide basic documents to support the application of internationally recognized quality management standards.
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.
IEC 61 207-1 :201 0, Expression of performance of gas analyzers – Part 1: General
3 Terms, definitions, and concepts
3.1 Terms and definitions
No terms and definitions are listed in this document.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.2 Concepts
3.2.1 High-temperature electrochemical sensor
3.2.1 .1 General The sensor is usually controlled at a stable, high temperature, typically in excess of 500 ° C. This high temperature is normally maintained by an electric heater, however, in some high- temperature in-situ applications, the sensor may require cooling to be applied. The sensor may also be run in passive mode with temperature sensing, where the heating is provided by the sample environment and the measured temperature is used in the calculation of the oxygen concentration. The high-temperature electrochemical sensor can be constructed in two basic forms: a) galvanic concentration cell; b) ion pump cell.
3.2.1 .2 Galvanic concentration cell (gauge cell)
3.2.1 .2.1 General Most commercially available analyzers employ the galvanic concentration cell consisting of two gas volumes or chambers, separated by an oxygen ion conducting solid electrolyte, and provided with a porous electrode on each side. The two sides are filled with sample gas on the one side and a fixed oxygen partial pressure reference gas on the other side. The reference gas shall contain some oxygen. The reference gas is usually air, but could be another constant oxygen partial pressure mixture or even a sealed reference where the oxygen partial pressure is maintained by a metal/metal oxide mixture. The electrodes are catalytic and the electrode/solid electrolyte interface at elevated temperature allows the formation of oxygen ions (O 2- ) which can then diffuse across the solid electrolyte interface. This interface remains an impenetrable barrier for the other gases present and thus provides a selective means of determining the partial pressure of oxygen present in the sample gas. The solid electrolyte is typically yttrium oxide (yttria)-stabilized zirconium oxide (zirconia), and the porous electrode is platinum based, although other materials may be used. The signal magnitude is temperature dependent and thus requires a low uncertainty of temperature measurement of the solid electrolyte interface by employing temperature sensors as given in IEC 60584 and IEC 60751 , and stability of heating provided to achieve the high temperatures required for efficient and sensitive operation.EN IEC 61207-2 pdf download.