How do you select a cable size(Cu&Al) for a particular load
Answer Posted / gulderaiym
Factors like the length of the cable, resistance, current
being carried by the cable , short circuit current, voltage
drop all come into play when selecting cable to be used.
First calculate the load current
I = P / x V x pf
pf =0,9 according to TCO Standard P-ST-2035, point 9.9
Then find apparent power
For three phase: S = x V x I
For single phase: S = V x I
Then I find the resistance by Ohm's law:
Z = V / I
V - is particular Load
Then find the short circuit current
I short circuit = S / Z
Then find cable size
S = I sh.circuit x / k k = 143, t = 1
And then select the cable according to the cable catalogs
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