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.
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Famous quotes containing the words breaking and/or capacities:
“There’s kind of a Sleeping Beauty magic about the kid. I thought I’d done something toward breaking the spell. Seems not. Prince Charmless, that’s me.”
—Dodie Smith, and Lewis Allen. Roderick Fitzgerald (Ray Milland)
“Mothers who have little sense of their own minds and voices are unable to imagine such capacities in their children. Not being fully aware of the power of words for communicating meaning, they expect their children to know what is on their minds without the benefit of words. These parents do not tell their children what they mean by “good” much less why. Nor do they ask the children to explain themselves.”
—Mary Field Belenky (20th century)