Engineering Board Exam Reviewer · Three-Phase Systems in Power Applications · hard
The balanced load shown has Z=30+j40, in each phase and is wye-connected to a 400 V line. If the same three impedances are reconnected in delta across the same line, what is the new line current?
- 4.62 A
- 8 A
- 13.9 A
- 41.6 A
Answer
C. 13.9 A
Solution
Wye: IL=400/ 3/50=4.62 A. Delta: Iph=400/50=8 A and IL= 3(8)=13.9 A. The delta line current is 3 times the wye line current.
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