Breaking Capacities
Miniature circuit breakers and fuses may be rated to interrupt as little as 75 amperes and are intended for supplementary protection of equipment, not the primary protection of a building wiring system. In North American practice, approved general-purpose low-voltage fuses must interrupt at least 10,000 amperes and certain types useful for large commercial and industrial low-voltage distribution systems are rated to safely interrupt 200,000 amperes. The rating of power circuit breakers varies according to the application voltage; a circuit breaker that interrupts 50,000 amperes at 208 volts might only be rated to interrupt 10,000 amperes at 600 volts, for example. Direct-current systems such as used with batteries present a special problem because current does not naturally reverse on each half-cycle, making interrupting of faults more difficult.
Read more about this topic: Breaking Capacity
Famous quotes containing the words breaking and/or capacities:
“The defects and faults of the mind are like wounds in the body; after all imaginable care has been taken to heal them up, still there will be a scar left behind, and they are in continual danger of breaking the skin and bursting out again.”
—François, Duc De La Rochefoucauld (1613–1680)
“If the children and youth of a nation are afforded opportunity to develop their capacities to the fullest, if they are given the knowledge to understand the world and the wisdom to change it, then the prospects for the future are bright. In contrast, a society which neglects its children, however well it may function in other respects, risks eventual disorganization and demise.”
—Urie Bronfenbrenner (b. 1917)