METROLOGY STANDARDS

METROLOGY STANDARDS: 

METROLOGY STANDARDS Electrical and Electronic Metrology Miguel Deogracias Sánchez

WHAT IS A NORM?: 

WHAT IS A NORM? It is a national, regional or international publication where there are unified parameters to which the products, processes and/or services must fit. They serve to prepare mistakes repetitive in the processes. They encourage the protection to the consumer across the quality of products and services.

HISTORY OF THE FIRST TIME: 

HISTORY OF THE FIRST TIME The history of the electrical norms begins with the activities realized by American Institute of Electric Engineers (AIEE). In 1884, the institute began to develop with big activity specifications normalized for the growth of the electrical industry. In 1890, it proposed that to be called Henry to the practical self-induction unit. At the same time, the institute named to his first committee of standardization, the Committee on Units and Standards . In 1893, as results of the congress that took place in Chicago, units were adopted for the force magnetomotriz (gilbert), for the flow (weber), for the reluctancia ( oersted ) and for the flow thickness (gauss). Later, the term was adopted " inductancia ", to represent the induction coefficient (with the symbol L) and Steinmetz proposed the current definition of the term " reactancia ", which was adopted.

THE FIRST ELECTRICAL NORMS: 

THE FIRST ELECTRICAL NORMS In 1896 a conference took place with the name of “National Conference of Standard Electrical Rules”. The conference was presided by teacher F. B. Crocker and in cooperation with other national organizations (E.U), the conference promulgated called "Underwriters Rules" or rules for insurers, who finally turned into National Electrical Code. At the beginning of 1898, a discussion was organized on the topic of “standardization of Generators, Engines and Transformers”. This one gave like turned out the formation of the first committee of the AIEE on norms of products.

NATIONAL BUREAU OF STANDARDS: 

NATIONAL BUREAU OF STANDARDS The institute was the first one in promoting the project of a law before the Congress of The United States, in 1901, to establish a national standardization department in Washington, “for the construction, care and comparison of norms or standards for use in scientific and technical work”. National Bureau of Standards went so far as to know this department like and it has had pronounced influence in the growth of the technology in the United States.

INTERNATIONAL ELECTRICAL NORMS: 

INTERNATIONAL ELECTRICAL NORMS In 1904 an international electrical congress was celebrated in St. Louis, that one sat precedent for later international congresses related to the units and electrical norms. The congress recommended in an unanimous way the establishment of two committees. The Committee 1 was formed by representatives of the government and was responsible for the legal conversation of the units and standards. This committee has evolved now to turn into the International Conference on Weights and Measures (GPMU). The Committee 2, of which it was elected president to Lord Kelvin, was responsible for the norms related to the commercial products used in the electrical industry and it turned later into International Electrotechnical Comisión (IEC). Another international body, the International Committee on Illumination (CIE) had his first meeting in 1913. The CIE establishes units, norms and nomenclature of international character, in the science and the technology of the light and the lighting

AMERICAN NATIONAL STANDARDS INSTITUTE (ANSI): 

AMERICAN NATIONAL STANDARDS INSTITUTE (ANSI) American Engineering Standards Committee (AESC) was organize in 1919 like result of the action of five organizations headed by the AIEE. This organization has been described correctly as a “national compensations camera for the industrial standardization” and has turned now into American National Standards Institute. In his first times this body was organized with 12 divisions. Few of these became active. The electrical engineering division, it became really more strongly, up to the point of having its own particular laws. In 1926 known then like American Standards Association (ASA), the abbreviations and symbols of engineering normalized. The AIEE, in cooperation with the ASA, sponsored in 1928 the making of a glossary of terms used in electrical engineering. This work was coordinated by the IEC .

STANDARDIZATION DURING THE SECOND WORLD WAR: 

STANDARDIZATION DURING THE SECOND WORLD WAR The needs for uniformity that were observed during the First World war, served as stimulus for the foundation of the AESC and accentuated the advantages of the standardization. This drove to the establishment of the Office of Industries of War. The pressure of the postwar period that developed towards the activities in norms and standards, took place for serious economic problems observed in the industry of the offices of the construction. This led to the development of diverse codes of construction and to the transfer of the responsibility of the Electrical National Code to National Bureau of Standards to the AESC, which had been reorganized by that time like American Standards Association (ASA). In 1921 there was created a Federal Office of Specifications to unify the specifications of the dependencies on the government. For 1942, already there was working a Joint Army-Navy Committee on Specifications and was responsible for the documents of military supplying known like “JAN Specs ”.

THE STANDARDIZATION IN THE CURRENT TIMES: 

THE STANDARDIZATION IN THE CURRENT TIMES The activities of international standardization, they were coordinated by the Organization of United Nations. This activity came to result in 1947 in the foundation of the ISO or International Organization for Standards. To this body he was made responsible for the standardization in all the fields that the IEC had not already covered. Two organizations, although separated and different, coordinate his activities and share a few common facilities placed in Switzerland . In the United States, the system of voluntary norms is developed and most of the organizations coordinate his activities through ANSI, American National Standards, organization that happened to the ASA.

ELECTRICAL STANDARDIZATION: 

ELECTRICAL STANDARDIZATION To be able to standardize the electrical equipment construction the Technical Norms have been created. In electrical projects, the norms indicate from the way how the graphic representations must be done, up to specifying the forms of assembly and test to which the teams must put. Every country possesses its own norms developed in accordance with the needs and experiences accumulated by the specialists. Between the most used electrical norms they can arrange to meet: National Electrical Code (NEC) American National Standards Institute (ANSI) National Electrical Manufacturers Association (NEMA) The Institute of Electrical and Electronics Engineeres Inc. (IEEE) Inside the European, most well-known norms they are: DIN, general German norms, inside which the norms VDE devote themselves to the electrical equipment ( Verband Deutscher Elektrotechnoker ) British Standard (BS) Union Technique d'Electricité (UTE) International Electrotechnical Commission (IEC)

ELECTRICAL UNITS: 

ELECTRICAL UNITS Coulomb (C, unit of electrical load) The introduction of the electrical magnitudes needs to add a new fundamental unit to the physicist: that of electrical load. This unit, which cannot stem from the units of the mechanics, was named Coulomb (C ) in honor to Charles- Augustin de Coulomb, first that measured straight the force between electrical charges. Due to the big difficulty of measuring straight the electrical charges exactly, there has taken as a basic unit, the unit of electric current, which in the International System of Units is the ampere . The load unit turns out to be then a derivative unit, which is defined as the quantity of electrical load that flows during 1 second across the section of a driver who transports a constant intensity of electric current of 1 ampere : C = A ∙ s

ELECTRICAL UNITS: 

ELECTRICAL UNITS Volt (V, unit of electrical potential and electromotive force ) The volt is defined as the potential difference along a driver when a current with an intensity of an ampere uses one watt of potency: V = J / C = m 2 ∙ kg / s 3 ∙ A Ohm (Ω, unit of electrical resistance) An ohm is the electrical resistance that exists between two points of a driver when a 1 volt constant potential difference applied between these two points produces, in the above mentioned driver, a current of intensity 1 ampere, when there is no electromotive force in the driver: Ω = V / A = m 2 ∙ kg / s 3 ∙ A 2

ELECTRICAL UNITS: 

ELECTRICAL UNITS Siemens (S, unit of conductancia electricity company ) A siemens is the electrical conductancia that exists between two points of a driver who has a resistance ohm : S = 1 / Ω Farad (F, unit of electrical capacity) One farad is the capacity of a condenser between whose armors there appears a difference of 1 volt electrical potential when it is loaded with a quantity of equal electricity on one culombio:40 F = A ∙ s / V = C / V = C 2 / J = = C 2 / N ∙ m = s 2 ∙ C 2 / m 2 ∙ kg = s 4 ∙ A 2 / m 2 ∙ kg

ELECTRICAL UNITS: 

ELECTRICAL UNITS Tesla ( T, unit of thickness of magnetic flux and inductividad magnetic) A tesla is a uniform magnetic induction that distributed normally on an one square meter surface, produces across this surface an entire magnetic flux of a weber : T = Wb / m 2 = V ∙ s 2 / m = kg / s 2 ∙ A Weber ( Wb , magnetic flux unit) A weber is the magnetic flux that, on having crossed a circuit of only one, it exhales, he produces in the same 1 volt electromotive force if the above mentioned flow is annulled in 1 second by uniform decrease: Wb = V ∙ s = T ∙ m 2 = m 2 ∙ kg / s 2 ∙ A

ELECTRICAL UNITS: 

ELECTRICAL UNITS Henrio (H, inductancia unit ) A henrio is the inductancia of a circuit in which a current that changes because of an ampere per second gives like turned out an one volt autoinduced electromotive force : H = V ∙ s / A = m 2 ∙ kg / s 2 ∙ A 2

PowerPoint Presentation: 

Thank you very much for your attention