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A power cord, line cord, or mains cable is a cable that temporarily connects an appliance to the mains electricity supply via a wall socket or extension cord. The terms are generally used for cables using a power plug to connect to a single-phase alternating current power source at the local line voltage—(generally 100 to 240 volts, depending on the location). The terms power cable, mains lead, flex or kettle lead are also used. A lamp cord (also known as a zip cord) is a light-weight, ungrounded, single-insulated two-wire cord used for small loads such as a table or floor lamp. A cord set includes connectors molded to the cord at each end (see Appliance coupler). Cord sets are detachable from both the power supply and the electrical equipment, and consist of a flexible cord with electrical connectors at either end, one male, and one female. One end of the cord set is attached to a molded electrical plug; the other is typically a molded electrical receptacle to prevent the possibility of having an exposed live prong or pin which would cause electric shock. The female connector attaches to the piece of equipment or appliance while the male plug connects to the electrical receptacle or outlet. ==Features== Power cables may be either fixed or detachable from the appliance. In the case of detachable leads, the appliance end of the power cord has a female connector to link it to the appliance, to avoid the dangers from having a live protruding pin. Cords may also have twist-locking features, or other attachments to prevent accidental disconnection at one or both ends. A cord set may include accessories such as fuses for overcurrent protection, a pilot lamp to indicate voltage is present, or a leakage current detector. Power cords for sensitive instruments, or audio/video equipment may also include a shield over the power conductors to minimize electromagnetic interference. A power cord or appliance coupler may have a retaining clamp, a mechanical device that prevents it from inadvertently being pulled or shaken loose. Typical application areas with stricter safety requirements include medical technology, stage and lighting technology, and computing equipment. For specialty equipment such as construction machinery, sound and lighting equipment, emergency medical defibrillators and electrical power tools, used in locations without a convenient power source, extension cords are used to carry the electric current up to hundreds of feet away from an outlet. In North America, the National Electrical Manufacturers Association develops standards for electrical plugs and receptacles and cables.〔(NEMA - Flexible Cords Section )〕 International power cords and plug adapters are used in conjunction with electrical appliances in countries different from those in which they were designed to operate. Besides a cord with one end compatible to receptacles or a device from one country and the other end compatible with receptacles or devices from another country, a voltage converter is usually necessary, as well, to protect travelers' electronic devices, such as laptops, from the differing voltages between the United States and places like Europe or Africa. North American lamp cords have two single-insulated conductors designed for low-current applications. The insulator covering one of the conductors is ribbed (parallel to wire) for the entire length of the cord, while the other conductor's insulator is smooth. The smooth one is hot and the ribbed one is neutral.〔Merle Henkenius; Popular Mechanics Dec 1987 How to Repair an Incandescent Lamp:Installing an in-line switch; p.130; () (retrieved 3/23/12)〕 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「power cord」の詳細全文を読む スポンサード リンク
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