Planning & EstimatingQuestion 370 of 521
A 1,500 ft² dwelling's standard-method calculation yields 13,100 VA on 240 V (about 55 A). What is the minimum service disconnect rating required?
a.60 A
b.90 A
c.100 A
d.70 A
Explanation
Even though the calculated demand is only about 55 A, a one-family dwelling service disconnect must be rated at least 100 A. The calculated load does not override the 100 A minimum, so the smaller ratings are not permitted.
Law Reference: 2023 NEC §230.79(C)Practice all 521 questions free — no signup required.
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