Answer Posted / engr.muhammad younas khan

SINGLE PHASE FORMULA FOR CABLE SIZING.

REQUIRED DATA:-
I :- AMPERES
L :- LENGTH OF CABLE.
K :- CONDUCTIVITY OF COPPER(58)
:- CONDUCTIVITY OF ALUMINUM (36)
Vd:- VOLTAGE DROP.

GIVEN DATA:
I:- 50 AMPERES.
L:- 100 METERS.
Vd:- 3% ACCEPTABLE OF 230 VOLTS

FORMULA:-
AREA (mm2)= 2*I*L/(K*Vd)
= 2*50*100/(58*6.9)
= 24.98 mm2
= ALMOST 25 mm2
FOR THREE PHASE:
AREA(mm2) = 1.732*50*100/(58*12)
= 12.44 mm2
= ALMOST 15 mm2
3% voltage drop of 400 volts =12 volts.

ABOVE EXPLAINED FOR IS PROPERLT CORRECT.USE AND ENJOY.

ENGR.MUHAMMAD YOUNAS KHAN
M.SC.ENGG.MIEE(UK)
WAZIRABAD CITY,PUNJAB, PAKISTAN
DATE:- 24/3/2014

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