Engineering Board Exam Reviewer · Three-Phase Systems in Power Applications · easy

In a balanced delta-connected load, the relationship between the line current IL and the phase current Iph is

  1. IL=Iph
  2. IL=Iph/ 3
  3. IL= 3,Iph
  4. IL=3Iph

Answer

C. IL= 3,Iph

Solution

At each corner of the delta the line current is the phasor difference of two phase currents 120° apart, giving IL= 3,Iph. The line voltage equals the phase voltage.

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