Core TradesQuestion 83 of 700
CALCULATION: A branch circuit is protected by a 20-ampere breaker. Applying the common rule that a continuous load should not exceed 80 percent of the breaker rating, what is the maximum continuous load in amperes?
a.12 amperes
b.16 amperes
c.18 amperes
d.20 amperes
Explanation
Maximum continuous load = 20 A x 0.80 = 16 amperes. The 80 percent rule keeps continuous loads from overheating the overcurrent device. 12 A uses 60 percent, 18 A uses 90 percent, and 20 A ignores the derating.
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