On 12/14/2010 10:18 AM, art davis wrote:
Yes they do, but you have to look past the marketing and look at the data sheet. According to the trip
curve for their "instant" breakers, the typical operating time for current of 2X the breaker
rating is just over 100 milliseconds, where the "non-instant breakers can hang in for over a second
at the same current. Definitely faster, but far from "instant". In fact the fastest time they
are guaranteed to operate is 10 milliseconds and that's at currents at least 8 X the breaker rating
(i.e. 160A for a 20A breaker).
So would you accept "instant" as being correct, if the breaker tripped
within a nanosecond of the short occurring for each foot the short was
from the breaker? (speed of light in wire)?
73, Jerry, K0CQ
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