if we want ot select cable size with reference to load current it take than wh

if we want ot select cable size with reference to load
current it take than what is the formula and it is same for
aluminium or copper?

Question Posted / jay pandya

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if we want ot select cable size with reference to load current it take than what is the formula an..

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

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if we want ot select cable size with reference to load current it take than what is the formula an..

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

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if we want ot select cable size with reference to load current it take than what is the formula an..

Answer / naveen perugu

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

Is This Answer Correct ?

4 Yes

8 No

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