At Fault 3:
R_f3=R_f2+R_c2

R_f3=0.0018 + 0.012

R_f3=0.0138

X_f2=X_f2+X_c2

X_f2=0.00711+0.00725

X_f2=0.01436

Z_f3=sqrt{{R_f3}^2+{X_f3}^2}

Z_f3=sqrt{0.0138^2+0.01436^2}

Z_f3=0.01992

S_f3=(kV_s)^2/Z_f3

S_f3=0.48^2/0.01992

S_f3=11.57~MVA

I_f3=1000*S_f3/{sqrt{3}*{kV_s}}

I_f3=1000*11.57/{sqrt{3}*{0.48}}

I_f3=underline{13,914}~A Fault current at Fault 3

(X/R)_f3={X_f3}/{R_f3}=0.0138/0.01436

(X/R)_f3=underline{1.04}

You can download the Impedance Method worksheet to help you better understand this method of short circuit calculation.

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