Services & DistributionQuestion 27 of 521
A conductor has an allowable ampacity of 115 A that does not match a standard fuse size. The load is 112 A. What is the largest standard OCPD permitted?
a.110 A
b.125 A
c.115 A
d.150 A
Explanation
Per 240.4(B), when the conductor ampacity does not correspond to a standard rating and is 800 A or less, the next higher standard device (125 A) is permitted. 115 A is not a standard size, 110 A is unnecessarily lower, and 150 A skips past the next standard.
Law Reference: 2023 NEC §240.4(B)Practice all 521 questions free — no signup required.
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