Equipment & SystemsQuestion 286 of 521
For the 75 kVA transformer with a 208 A secondary, what is the maximum secondary overcurrent protective device using the 125% value of Table 450.3(B)?
a.208 A
b.260 A
c.347 A
d.416 A
Explanation
Table 450.3(B) allows secondary protection at 125% of rated secondary current (currents >=9 A): 208 x 1.25 = 260 A. 208 A omits the factor, 347 A is about 167%, and 416 A is 200%.
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