IEC 61207-3:2019 pdf free download

IEC 61207-3:2019 pdf free download

IEC 61207-3:2019 pdf free download Gas analyzers – Expression of performance – Part 3: Paramagnetic oxygen analyzers
This part of lEC 61207 applies to the three main methods for measuring oxygen by its
paramagnetic property, which are outlined in the introduction. Ilt considers essential ancillaryunits and applies to analyzers installed indoors and outdoors.
Safety-critical applications can require additional requirements from system and analyzerspecifications not covered in this document.
This document is intended
to specify terminology and definitions related to the functional performance of para-magnetic gas analyzers for the measurement of oxygen in a source gas;
to unify methods used in making and verifying statements on the functional performance ofsuch analyzers;
to specify what tests are performed to determine the functional performance and how suchtests are carried out;
to provide basic documents to support the application of internationally recognized qualitymanagement standards.
Normative references
The following documents are referred to in the text in such a way that some or all of theircontent constitutes requirements of this document. For dated references, only the edition
cited applies. For undated references, the latest edition of the referenced document (includingany amendments) applies.
IEC 61207-1, Expression of performance of gas analyzers – Part 1: General
3Terms and definitions
For the purposes of this document, the following terms and definitions apply.
NOTE Although cgs (centimetre-gram-second)units have been used in this document, sl (Systeme International)units (such as defined in lUPAC[1] 1) can also be used.
lSO and IEC maintain terminological databases for use in standardization at the followingaddresses:
IEC Electropedia: available at http://www.electropedia.orgl
Iso Online browsing platform: available at
Note 1 to entry:
See Figure 1 .
Note 2 to entry: The measuring cell typically employs a glass dumb-bell, with the spheres containing nitrogen, suspended on a torsion strip between magnetic pole pieces or magnets that produce a very strong magnetic field gradient around the dumb-bell. The dumb-bell is then deflected when oxygen molecules enter the measuring cell, a force being exerted on the dumb-bell by the oxygen molecules which are attracted to the strongest part of the magnetic field. By use of an optical lever, a magnetic actuation coil, and suitable electronics to generate a feedback signal that nulls the magnetic susceptibility force, an output that is directly proportional to the partial pressure of oxygen can be achieved. The transducer can be maintained at a constant temperature to prevent the variations in magnetic susceptibility to temperature from introducing uncertainties. Alternatively, built-in temperature sensors may be used to provide temperature compensation of the oxygen reading. Additionally, the elevated temperature helps in applications where the sample is not particularly dry. Some analyzers are designed so that the transducer operates at a temperature in excess of 373,1 5 K (1 00 °C) to further facilitate applications where condensates would form at a lower temperature. Paramagnetic sensor orientation may also affect the oxygen measurement uncertainty and this may be corrected by using a compensation algorithm using, for example, a three-dimensional accelerometer to determine the sensor orientation relative to its orientation during calibration. Due to the mechanical nature of this type of device, there is some inherent susceptibility to vibrational and gyroscopic motion, potentially resulting in increased measurement uncertainty.