Theory & Safety第 113 / 120 题
A balanced delta-connected load has a phase current of 20 amperes. What is the line current?
a.20 amperes
b.Approximately 34.6 amperes
c.Approximately 11.5 amperes
d.60 amperes
解析
In a delta connection each line conductor feeds two phase windings, so line current equals 1.732 times phase current: 20 x 1.732 = 34.6 amperes. The 20-ampere answer describes a wye connection, 11.5 amperes divides instead of multiplying, and 60 amperes triples the value rather than applying the square root of three.
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