Answer / mahesh sali

while selection of cable u should followed the below steps ;

1) cal. the full load current If.L= ( kw / 1.732 x v x
p.f. )

Assume the voltage drop of system as per application says
for motor it should be 10% Vd = 10%

2) Vd = ( 10/100) * v

3) Vd/ph. = ( Vd/1.732 )

4) R = vd/ph./IF.L

5) R-Rho*L/A

Assume , for Copper cable Rho = 1.72 e-8 Ohm-m
L = Length of cable
Base on the above assumation u can easily cal. the size of
cable.

After cal. the cable size , add. 25% extra in ur cal. the
cable size .

Thanking u

Answer / k.prakashchandra

In case of transformers, for copper cable 2.5A/sq mm and Al
i.5A/sq mm ,for generators 1.5A/sq mm and 1 A/sq mm
respectively.For others 4A & 2.5A per sq mm

Answer / naveen perugu

for copper cable 4Amps/Sqmm is the standard practice and
for alluminium 3Amps/sqmm is the standard practice for
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