Engineering Board Exam Reviewer · Three-Phase Systems in Power Applications · hard
A balanced delta load has Z =60+j45, in each phase and is supplied from a 400 V line. Replace the delta with its equivalent wye and find the line current.
- 9.24 A
- 5.33 A
- 3.08 A
- 18.5 A
Answer
A. 9.24 A
Solution
ZY=Z /3=20+j15, , so |ZY|=25, . IL=VL/ 3/|ZY|= 231 V25, =9.24 A. (Check: delta phase current 400 V75, times 3 gives the same 9.24 A.)
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