Question 8.2: For the system considered in Example 8.1, estimate the motor......

Energy-Efficient Electrical Systems for Buildings [1086323]

For the system considered in Example 8.1, estimate the motor contribution and determine the total short-circuit current at Point A.

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Using Equation 8.6 and the fact that the voltage of the system is $480 \ A$

$I_{SC,M}=4\times \sum{I_M}$ (8.6)

I_{SC,M}=4I_{L,S}=4\times 1202=4808 \ A

Therefore, the final short-circuit current at point A, $I_{SC,A}$ , can be calculated:

I_{SC,A}=24056+4808=28,800 \ A

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