Electrical standards

Each country still tends to maintain local standards classifications but these are directly equivalent to the European Norms. For instance an electrical design and manufacture applicable to process chromatographs is British Standard BS 2771 [6] (Electrical Equipment of Industrial Machines) which is equivalent to European Norm EN 6024. 

In addition the nature of the environment in which chromatographs are installed, and their use with the potential for liquid leaks or wash down will necessitate that enclosures meet the appropriate standards for dust and water protection (Table l-I). Most installations will utilize IP54 protection. 

Protection against solid bodies Protection against liquids  

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NFPA 79 Electrical Standard for Industrial Machinery. National Fire Protection Association, Quincy, MA. 

An advantage of the technique is the use of an electrical standard to replace chemical standards and the problems associated with their preparation and stability. The coulometric titration also permits the generation of reagents such as copper(I) or bromine, which are difficult to employ as standard solution, or others such as silver(II) or chlorine, which are virtually impossible to use in any other way. A disadvantage of the coulometric titration is its lack of specificity. 

The desk top computer network is shown in Figure 1. The liquid scintillation counters which we routinely use to generate metabolism data include two Beckman LS-200 series liquid scintillation counters and two Tracor Mark III liquid scintillation counters, however, other LSC makes and models may be interfaced. The Tracor counters are equipped with two standard communications output connectors. One is used to drive the printer, the other is available to the user. The Beckman counters use a unique teletype driver but an interface produced by William Palmer Industries can split the signal and provide a standard communication output. Therefore, all data output from the liquid scintillation counters are available in an electrical standard format, RS-232C. Hardware interfacing was therefore simplified and data collection was a matter of software development. 

The fine structure constant a can be determined with the help of several methods. The most accurate test of QED involves the anomalous magnetic moment of the electron [40] and provides the most accurate way to determine a value for the fine structure constant. Recent progress in calculations of the helium fine structure has allowed one to expect that the comparison of experiment [23,24] and ongoing theoretical prediction [23] will provide us with a precise value of a. Since the values of the fundamental constants and, in particular, of the fine structure constant, can be reached in a number of different ways it is necessary to compare them. Some experiments can be correlated and the comparison is not trivial. A procedure to find the most precise value is called the adjustment of fundamental constants [39]. A more important target of the adjustment is to check the consistency of different precision experiments and to check if e.g. the bound state QED agrees with the electrical standards and solid state physics. 

In the course of the integration of European states and the removal of trade barriers, national standardization loses importance considerably. The majority of electrical standards comes into existence by international cooperation with IEC, International Electrotechnical Commission, Geneva/Switzerland. On the basis of IEC Standards many European Standards have been developed in the past. This work has been done by CENELEC, Comite Europeen de Normalisation Electrotechnique, Brussels/Belgium. European Standards or Norms (EN) often deviate from their IEC origins in their technical content. To avoid double action and to ensure a more effective standardization procedure, IEC and CENELEC are now working in closer cooperation. CENELEC is a private organization and does not act as an institution of the European Union at all. This fact indicates that European Standards need a legal act to come into force. Members of CENELEC are the national committees for standardization of the member states (not identical with the European Union). 

Mercury has a high density (13.546 g cm" at 20 °C) and a wide liquid range (mp -38.9 °C bp 357) over most of which its volume expands uniformly. In addition, the high surface tension of mercury keeps it from sticking to glass surfaces. These properties have contributed to its use in an impressive number of laboratory applications. For a metal, mercury has an unusually high electrical resistivity or specific resistance (95.8 J,S2 cm), and this property enables it to be used as an electrical standard. Of all the common metals, only bismuth has a higher resistivity. 

Within this classical picture a kind of electric standard atmosphere may be constructed as shown in Table 1. 

IEC61089 Round wire concentric lay overhead electrical standard conductors. 

National Fire Protection Association (NFPA)—A non-governmental professional association whose members specialize in safety and health standards related to fire protection, including the electrical standards in the National Electrical Code. Online at http //www.nfpa.org/index.asp. 

Electrical Parameters of the Clear (Fair-Weather) Atmosphere, Pertinent to the Classical Picture of Atm. Electridty (Electric Standard Atmosphere)... 

Equip motor-driven electrical equipment used in a laboratory where volatile flammable materials may be present (e.g., a hydrogenation room) with either nonsparking induction motors that meet Class 1, Division 2, Group C-D electrical standards (U.S. DOC, 1993) or air motors instead of series-wound motors that use carbon brushes, such as those generally used in vacuum pumps, mechanical shakers, stirring motors,... 

Comite Europeen de Normalisation Electrotechnique (CENELEC), for electrical standards. 

International electrical standards) lEE The Institution of Electrical Engineers... 

Arnold, H.J. Sanctions and rewards Organizational perspectives. In Sanctions and Rewards in the Legal System A Multidisciplinary Approach. Toronto, Ontario, Canada University of Toronto Press, 1989. ASHE Electrical Standard Compendium, 1999 ed. Chicago, IL American Society of Healthcare Engineering. ASHRAE Handbook 2003, HVAC Applications. 

Criteria for determining whether shop-made cord sets meet existing electrical standards include ... 

No specific training requirements is mentioned in the electrical standard. However, you must always instruct each employee in the recognition and avoidance of unsafe conditions and the regulations applicable to his work environment to control or eliminate any hazards or other exposure to iUness or injury. ... 

The OSHA electrical standard requires your employer to provide either (1) GFCIs for receptacle outlets in use and not part of the permanent wiring of the structure or (2) an assured equipment grounding conductor program covering all cord sets, receptacles that are not part of the permanent wiring of the structiore, and equipment connected by cord and plug that are for use by employees. 

Normally, electrical equipment must be approved as an assembly by a nationally-recognized testing laboratory to be acceptable under the General Industry or Construction Electrical Standards (Part 1910, Subpart S and Part 1926, Subpart K, respectively). 

National Electrical Manufacturers Association (NEMA) (Electrical Standards and Product Guide, ESPG)... 

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