The Overload Myth An "overload" occurs when a conductor has to carry much more current than it was designed for; it may get so hot that it will burn or melt off its protective insulation and cause a fire by igniting nearby combustibles. An overload of this severity is quite uncommon, though - especially in home wiring. An image which may spring to many people's minds is the overburdened electrical outlet covered with multi-adapters and half a dozen appliances plugged in to them. The outlet and the house wiring, under most normal household situations, are usually quite capable of handling the extra current required by the devices plugged in, and the circuit breaker provides added protection. A fire is far more apt to begin here because of mechanical damage (abuse) or a poor connection (which can produce abnormal heating) than an overload of current. Extension cords, often
accused as overload culprits, can carry at least twice their rated current amounts without
getting warm to the touch, and are difficult to overload in the average house. Common
failings of these cords include poor connections or arcing or "short circuits"
caused by damage to the cord's insulation. Extension cords are frequently abused and used
incorrectly, and do cause fires as a result. In addition, the construction quality of some
imported extension cords can be questionable. |
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