Equipment & SystemsQuestion 283 of 521
A rooftop A/C unit has one compressor at 30 A rated-load and a condenser fan at 1.5 A. What is the minimum circuit ampacity (MCA), using 125% of the largest motor plus other loads?
a.37.5 A
b.31.5 A
c.39 A
d.40.5 A
Explanation
MCA = (30 x 1.25) + 1.5 = 37.5 + 1.5 = 39 A. 37.5 A forgets the fan, 31.5 A applies 125% to a wrong base, and 40.5 A applies 125% to both loads.
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