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NEMA connectors are power plugs and receptacles used for AC mains electricity in North America and other countries that use the standards set by the US National Electrical Manufacturers Association. NEMA wiring devices are made in current ratings from 15 to 60 amperes, with voltage ratings from 125 to 600 volts. Different combinations of contact blade widths, shapes, orientation, and dimensions create non-interchangeable connectors that are unique for each combination of voltage, electric current carrying capacity, and grounding system. NEMA 1 (two-prong, no DC safety ground) and NEMA 5 (three-prong, with safety ground pin) connectors are used for commonplace domestic electrical equipment; the others are for heavy duty or special purposes. NEMA 5–15R is the standard 15 amp capacity electric receptacle (outlet) found in the United States. Similar and interchangeable connectors are used in Canada and Mexico. The dimensional standard for electrical connectors is ANSI/NEMA WD–6 and is available from the NEMA website.〔 ==NEMA nomenclature== There are two basic classifications of NEMA device: straight-blade and locking. The straight-blade 5–15 and 5–20 are found nearly everywhere in countries using the NEMA standards, and are intended for supplying lighter-duty, general-purpose electrical devices. Twist-locking types are used for heavy industrial and commercial equipment, where increased protection against accidental disconnection is required. Numbers prefixed by "L" are curved-blade, twist-locking connectors; others are straight blade and non-locking. The metal conductive blades are sometimes informally called "prongs" (as in "3-prong plug"). The numeral preceding the hyphen in NEMA nomenclature indicates the configuration, that is, the number of poles, number of wires, voltage, and whether single- or three-phase. A grounding type of device is described as two-pole, three-wire; or four-pole, five-wire; etc. A non-grounding device may be two-pole, two-wire; or three-pole, three-wire; etc. The numeral following the hyphen is the rating of the device in amperes. The number is followed by the letter R to indicate a receptacle (female connector) or the letter P to indicate a plug (male connector). As an example, the 5–15R is the common 125 V two-pole, three-wire receptacle. The L5–15R, while sharing the same electrical rating, is a locking design that is not physically compatible with the straight-blade 5–15 design. The 5–30 has the same two-pole, three-wire configuration and 125 V rating, but is rated 30 A. Although there are several non-grounding device types in the NEMA standards, only three of them are in widespread use today. These are the two-pole 1-15, still in use in millions of buildings built before the 1960s, and the three-pole 10–30 and 10–50. The small hole near the end of the power (non-ground) blades of some NEMA plugs is used for convenience in manufacturing; if present, it must be of specified diameter and position.〔(ANSI/NEMA WD–6 ''Wiring Devices Dimensional Specifications'' )〕 Small specialized padlocks are available to fit these holes, allowing "lockout" of hazardous equipment, by physically preventing insertion of locked plugs into a power receptacle. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「NEMA connector」の詳細全文を読む スポンサード リンク
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