How to select the cable size for the given load ?Pls
explain the Formulae

Answer Posted / sree

presuming, the unit of load is in HP(It is out put power)
output in KW= 735.5xHP(A).
Input in KW= A/Effy.(B).
Current= B/((1.732 * V * 0.7) (for 3 Phase star connected
load)(C)
Starting current= (1.5 to 2 times of full load current
(approx.)(D)

Based on cable catalague the size of cable will be chosen
as per above current rating(D).

or

Presuming the load is in KW(It is input power)
current=KW/((1.732 * V * 0.7) (for 3 Phase star connected
load)(A).
Starting current= (1.5 to 2 times of full load current
(approx.)(B)

Based on cable catalague, the size of cable will be chosen
as per above current rating(B).

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