Kiểm tra & Khắc phục sự cốCâu 510 / 521
Three parallel loads on a 120 V circuit draw 4 A, 6 A, and 5 A respectively. What total current should a clamp meter read on the feeder conductor?
a.5 A
b.15 A
c.120 A
d.1.6 A
Giải thích
Currents in parallel branches add: 4 + 6 + 5 = 15 A on the common feeder. Option a is only one branch, c confuses voltage with current, and d inverts the sum. This is why the feeder must be sized for the combined load.
Luyện miễn phí toàn bộ 521 câu hỏi — không cần đăng ký.
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