IEC 60746-1-2003 pdf – Expression of performance of electrochemical analyzers – Part 1: General.
1 Scope This standard is intended: – to specify the terminology and definitions of terms related to the performance charac- teristics of electrochemical analyzers used for the continuous determination of certain aspects of (generally aqueous) solutions; – to specify uniform methods to be used in making statements on the performance characteristics of such analyzers; – to specify general test procedures to determine and verify the performance characteristics of electrochemical analyzers, taking into account the differences of approach in IEC documents specifying test methods (IEC 60359, IEC 60770, IEC 61298); – to provide basic documents to support the application of standards of quality assurance: ISO 9001, ISO 9002 and ISO 9003. 2 Normative references The following referenced documents are indispensable for the application 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 60068-1, Environmental testing – Part 1: General and guidance IEC 60359:2001, Electrical and electronic measurement equipment – Expression of performance IEC 60381-1, Analogue signals for process control systems – Part 1: Direct current signals IEC 60382, Analogue pneumatic signal for process control systems IEC 60654-1, Industrial-process measurement and control equipment – Operating conditions – Part 1: Climatic conditions IEC 60770-1, Transmitters for use in industrial-process control systems – Part 1: Methods for performance evaluation IEC 61298, (all parts): Process measurement and control devices – General methods and procedures for evaluating performance ISO 9001, Quality management systems – Requirements ISO 9002, Quality systems – Model for quality assurance in production, installation and servicing ISO 9003, Quality systems – Model for quality assurance in final inspection and test
3 Terms and definitions For the purposes of this standard, the following definitions apply. These definitions are based on those in IEC 60359. Additional definitions from IEC 60770 are included for performance characteristics appropriate to electrochemical analyzers. The definitions have, in some cases, been clarified and directed towards relevance to electrochemical analyzers. The reconciliation of the quantities used to define performance characteristics in this document with those referred to in IEC 60359, IEC 60770 and IEC 61298 is discussed in clause 4. 3.1 electrochemical analyzer measuring instrument that provides an indication of a specific property of a medium by use of a sensor which responds to ions from electrolytes (or ions generated from reactions with non-electrolytes) in that medium NOTE The analyzer may comprise of separate parts, see below. 3.2 sensor that part of the electrochemical analyzer (which may be a separate unit) which is in contact with the medium in which the property is to be measured NOTE In general an electrical output related to that property of the sample which is to be measured is derived from this part of the analyzer. Examples of electrochemical sensors are: pH, ion-sensitive and redox potentiometric cells, dissolved oxygen cells, conductance cells. 3.3 electronic unit device converting the electrical signal from the sensor to a defined, scaled, output signal 3.4 simulator device which provides well-defined electrical properties similar to a specific type of sensor NOTE It may therefore be used to determine the performance characteristics of the electronic unit alone. It must exhibit uncertainties that are negligible in comparison with the specifications of performance characteristics to be determined. 3.5 calibration solution solution of known value of the property being measured, used for periodic calibration and for various performance tests. NOTE 1 The value should be expressed in SI units compatible with ISO 31.
3.8 conventional true value value approximating to the true value of a quantity such that, for the purpose for which that value is used, the difference between the two will be regarded as negligible NOTE 1 Since the “true value” cannot be known exactly, for the sake of simplicity and where no ambiguity exists, the term “true value” may be used where the term “conventional true value” is meant. NOTE 2 See 3.1.13 of IEC 60359. 3.9 performance characteristic one of the quantities assigned to an apparatus in order to define its performance by values, tolerances, ranges, etc. 3.10 influence quantity any quantity, which is not the subject of the measurement but which influences the indication of the measuring equipment NOTE Influence quantities may interact in their effect on the measuring equipment. 3.11 variation difference between the values indicated by an analyzer for the same value of the property being measured when a single influence quantity assumes successively two different values 3.12 rated value value assigned to a performance characteristic of the analyzer by the manufacturer NOTE See 3.3.8 of IEC 60359. 3.13 range domain between the upper and lower limits of the quantity under consideration NOTE 1 The term “range” is usually used with a modifier. It may apply to a performance characteristic or an influence quantity, etc. For example, the Rated Measuring Range is the set of values of the property to be measured, corresponding to the Output Signal Range of the analyzer (for example 4 mA – 20 mA, etc). NOTE 2 See 3.3.2 of IE 60359.