A balanced 480-volt three-phase feeder supplies 49,883 volt-amperes. Using 1.732 for the square root of three, approximately what line current is required?

Texas Journeyman exam practice question · Feeder Calculations

A balanced 480-volt three-phase feeder supplies 49,883 volt-amperes. Using 1.732 for the square root of three, approximately what line current is required?

60 amperes
B104 amperes
C34.6 amperes
D23,944 amperes

Why A is correct

Three-phase apparent power equals 1.732 times line voltage times line current. Dividing 49,883 by 1.732 and then by 480 gives approximately 60 amperes.

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A balanced 480-volt three-phase feeder supplies 49,883 volt-amperes. Using 1.732 for the square root of three, approximately what line current is required?

A balanced 480-volt three-phase feeder supplies 49,883 volt-amperes. Using 1.732 for the square root of three, approximately what line current is required?

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