Answer Posted / sujata wagh

Generally current carrying capacity of Al. is 0.8A per
sqmm and Copper is 1.6A per Sqmm.

Suppose we need bus bar for 630A, and we are going with
Aluminium bus bar

= 80*10*.8=640A
where 80*10 is size if bus bar usually available is the
market.
so we can use 80x10sqmm al. busbar per phase for 630A.

for TPN- (3.5)x80x10


If we are going with Copper bus bar
than we will use = 40x10sqmm per phase

= 40x10x1.6=640A
where 40*10 is size if bus bar usually available is the
market.
so we can use 40x10sqmm copper busbar per phase for 630A.

for TPN- (3.5)x40x10

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