NEMA National Electric Manufacturers specifications

Each segment of the insulated wire and cable industry has its own set of standards, and cables are built to conform to specifications provided by a large variety of technical associations such as The Institute of Electrical Electronic Engineers (IEEE), The Insulated Cable Engineers Association, (ICEA), National Electrical Manufacturers Association (NEMA), Underwriters Laboratories (UL), Rural Electrification Administration of the U.S. Department of Agriculture (REA), Association of Edison Illumination Companies (AEIC), MiUtary Specifications of the Department of Defense (MIL), American Society for Testing and Materials (ASTM), National Electrical Code (NEC), etc. 

Electrical Laminates. A significant use for epoxy resins is in the manufacture of copper-clad epoxy-glass printed circuit boards. Systems are available that meet the National Electrical Manufacturers Association (NEMA), GIO, Gil, FR3, FR4, FR5 specifications. Currently the majority of boards are manufactured to the fiame-retardant FR4 specification. The flame retardance is achieved by the use of a soHd epoxy resin based on... 

Environmental Enclosures Enclosures for valve accessories are sometimes required to provide protection from specific environmental conditions. The National Electrical Manufacturers Association (NEMA) provides descriptions and test methods for equipment used in specific environmental conditions in NEMA 250. Protection against rain, windblown dust, hose-directed water, and external ice formation are examples of environmental conditions that are covered by NEMA standards. 

National Electrical Code (NEC), 21 847 National Electrical Manufacturers Association (NEMA), 17 843 specifications, 10 453-454 National Emission Standard for Hazardous Air Pollutants (NESHAP), 1 812 21 585... 

In the USA the National Electrical Manufacturing Association (NEMA) places certain standards on electrical products. This organisation has established a NEMA type coding system for enclosures. Each type, numbered from 1 to 13, describes a specific type of protection, see ANSI/NEMA standard 250. 

Standard test methods for plastics are provided by many different agencies including, American Society of Testing and Materials (ASTM), the US Government (Military and Federal Specifications), National Electrical Manufacturers Association (NEMA), Society of Automotive Engineers (SAE), etc. 

The most commonly referenced specification for base materials is IPC-4101, Specification for Base Materials for Rigid and Multilayer Printed Boards. Historically, the National Electrical Manufacturers Association, NEMA, has also been used in specifying base materials. 

One of the first classifications of base materials for printed drcnits (and other electrical components) was completed by the National Electrical Manufacturers Association (NEMA). NEMA s industrial laminating thermosetting products standard documents many of the materials used in printed circuits as well as specifications for some of their properties. Historical NEMA grades are outlined in Table 6.1 and cross-referenced with IPC-4101 in Table 6.2. Some of the commonly used materials have been FR-2, CEM-1, CEM-3, and, of course, FR-4. 

National Electrical Manufacturers Association Standards. National Electrical Manufacturers Association (NEMA) standards establish dimensions, ratings, and performance requirements for electric equipment, regardless of manufacturer. NEMA standards are used widely in specifications. 

Practical considerations almost always play a role in choosing a near-IR spectrometer, reflecting specific demands that may be placed by a specific application. Among these considerations are size and/or portability speed susceptibility to extreme (e.g. industrial) environments cost measurement type and flexibility (e.g. can the spectrometer be used only for transmittance measurements, or are reflectance and/ or fibre optic measurements feasible ). Manufacturers consider all of these factors. For example, it is common to find commercial instrumentation housed in enclosures that are ruggedized to meet specific industry standards (National Electrical Manufacturers Association - NEMA). 

In addition to ASTM, several other groups, such as the National Electrical Manufacturers Association (NEMA), the Underwriters Laboratories (UL), the Institute of Electrical and Electronics Engineers (IEEE), and several US. government agencies issue plastics specifications, as do German (VDE and DIN) and British (BSD agencies. International standards are coordinated and written by the International Electrotechnical Commission (lEC). Despite such extensive and useful standardization activity, relatively little emphasis has been placed on the... 

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