Definition
An arc flash is an electric arc supplied with sufficient electrical energy to cause substantial damage or harm, fire or injury.
- Electrical arcs, however, fed by limited energy and well controlled, produce very bright light (as in arc lamps—enclosed, or with open electrodes), and are also used for welding and other industrial applications.
Arc flash temperatures can reach or exceed 35,000 °F or approx 20,000 °C at the arc terminals. The massive energy released in the fault rapidly vaporizes the metal conductors involved, blasting molten metal and expanding plasma outward with extreme force. A typical arc flash incident can be inconsequential but could conceivably easily produce a more severe explosion (see calculation below). The result of the violent event can cause destruction of equipment involved, fire, and injury not only to the worker but also to nearby people.
In addition to the explosive blast of such a fault, destruction also arises from the intense radiant heat produced by the arc. The metal plasma arc produces tremendous amounts of light energy from far infrared to ultraviolet. Surfaces of nearby objects, including people absorb this energy and are instantly heated to vaporizing temperatures. The effects of this can be seen on adjacent walls and equipment - they are often ablated and eroded from the radiant effects.
Read more about this topic: Arc Flash
Famous quotes containing the word definition:
“I’m beginning to think that the proper definition of “Man” is “an animal that writes letters.””
—Lewis Carroll [Charles Lutwidge Dodgson] (1832–1898)
“... we all know the wag’s definition of a philanthropist: a man whose charity increases directly as the square of the distance.”
—George Eliot [Mary Ann (or Marian)
“It is very hard to give a just definition of love. The most we can say of it is this: that in the soul, it is a desire to rule; in the spirit, it is a sympathy; and in the body, it is but a hidden and subtle desire to possess—after many mysteries—what one loves.”
—François, Duc De La Rochefoucauld (1613–1680)