The so-called “arc-in-a-box” has a focusing effect in which radiated energy strikes the back and sides of the box, reflecting out in a higher concentration of energy than would be obtained in open air. Your distribution box, the unsung hero of your home's electrical infrastructure, has just suffered an arc fault. It happens in a fraction of a second – even faster that you can blink your eye and can have devastating consequences for anyone exposed. When it occurs, equipment damage is already underway, and the probability of escalation into arc flash conditions. An arc is created by ionization of a gas (normally air) by means of an electric discharge between electrodes of different potential or phase angle, or between an electrode and earth. The term "arc discharge" is also common. If this effect is caused by a fault, such as a short circuit inside a.
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