Solving Delta Connected Load: Find Phase Current in PU and SI Units

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SUMMARY

The discussion focuses on calculating the phase current for a balanced delta-connected load rated at 10 KVA and 500V, operating at 90% nominal voltage and 100% line current. The correct per unit line current is established as 0.58 pu, while the phase current in SI units is calculated to be 6.7A. The confusion arises from the relationship between line current and phase current in a delta configuration, specifically that the phase current is derived from the line current divided by the square root of three (Iphase = Iline/√3). Additionally, it is clarified that delta connections yield one-third of the instantaneous power due to the distribution of current across phases.

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vvl92
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A balanced 3 phase load is rated at S=10KVA and 500V. The device is operating at 90% nominal voltage and 100 % line current.

The question is:
if the load is delta connected, find the phase current in per unit and SI units.

I calculated correctly that the per unit line current value is 0.58 pu, but the answer given for Ip=6.7A and I don't see why.

I calculated S=VI* S/V=I*=20A and 6.7 is 20/3...I thought that for delta connected load, you Iphase=Iline/√3... I am out by a factor of 1/√3 please explain!
 
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Also can anyone explain why delta connection produces 1/3 of the instantaneous power given the same Z and V?
 

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