how to claculate earth strip size for 1500kVA transformer
for neutral and body

Answer Posted / bala.a

you will follow as per State electricity board norms - 50
x 6 mm Cu for Nu and 50 x 6 mm GI FOR body 0r
you will calculate as per short circuit calculation
Formula 0.0054 x root t x I
Where
t =1 second
I = SHORT CIRCUIT CURRENT
example
Fault current- 33kA( assumed )
0.0054 x root 1 x 33000= 178.2 mm
so you will recommended 50 x 4 mm Cu

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