Question 13009 of 790 · California General Electrician Exam
A three-phase 480 volt motor draws 40 amperes per line at a power factor of 0.85. What is the true power input?
Exactly one answer is correct.
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Correct answer to question 13009
- A: 28.3 kW
Explanation
True power is P = E x I x 1.732 x PF = 480 x 40 x 1.732 x 0.85 = about 28,265 W, or 28.3 kW. Leaving out the power factor gives 33.3 kVA (apparent power), and leaving out 1.732 gives 16.3 kW.
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