Evaluation of Natural Gas Electronic Corrector’s Software Performance According AGA NX-19

As the definition, Reliability is the degree of consistency of a measure. A test will be reliable when it gives the same repeated result under the same conditions. Reliability and validity are often confused; the terms describe two inter-related but completely different concepts. Very simply Validity is Does the test actually measure what it’s supposed to but Reliability defines as Does the test consistently give the same result under the same conditions . Every metric or method we use, including things like methods for uncovering usability problems in an interface and expert judgment, must be assessed for reliability. In fact, before you can establish validity, you need to establish reliability. Reliability is a property of any measure, tool, test or sometimes of a whole experiment. It’s an estimation of how much random error might be in the scores around the true score. Instrument reliability is a way of ensuring that any instrument used for measuring experimental variables gives the same results every time.Fiscal Measurement must not be confused with Custody Transfer; in fact, fiscal measurement is a more general term meaning measurement for money that includes both allocation and custody transfer flow measurement. Gas custody transfer flow measurement can take place anywhere along the process value chain from the wellhead to delivery or sale location. The dynamics of where these transactions are actually located can be influenced by a number of factors with the two primary ones being regulation and commercial arrangement. However for the lowest uncertainty in measurement, custody transfergenerally takes place at stable, predictable single phaselocations or physical discrete hand-over points (e.g. platform/production exit location, pipeline entry/exit, terminal entry etc.). These locations generally provide the favorable conditions that flow measurement devices can operate predictablyand repeatability.The measurement standards are one of the most accessible methods for calculating the correction factor, and the NX-19 method is one of the simplest and easiest methods, because it has the lower dependence on measurement parameters, such as the components of natural gas compounds. Therefore, this method has been considered in measurements of gas consumption by major customers at the National Iranian Gas Company. In this research we try to compare 10 different brands of Electronic Correctors that using in natural gas metering stations. We gave 20 different data for different condition of using these correctors for each one, and then compare the results of statistical values. Finally we present the research results.

Keywords:

Natural Gas , Metering systems , Gas Electronic Correctors , Reliability , Software Performance , AGA NX-19