Kiểm tra & Khắc phục sự cốCâu 512 / 521
A single-phase load operates at 240 V and draws 20 A at unity power factor. What is its power in kilowatts?
a.12 kW
b.0.083 kW
c.4.8 kW
d.48 kW
Giải thích
P = V x I = 240 V x 20 A = 4,800 W = 4.8 kW at unity power factor. Option a inverts, b divides V by I, and d misplaces the decimal. Confirming measured watts against the nameplate is part of functional commissioning.
Luyện miễn phí toàn bộ 521 câu hỏi — không cần đăng ký.
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