Answer / a.bala

Hai Ramya
The formula for I= KW/ 1.732x pf x Applied voltage in kv
So
KW =30
pf=0.8
Applied voltage = 440 v =440/1000=.440
30/ 1.732x0.8x.440=49.2 A

Answer / dinesh raj

Voltage =440 V
Power Facter (cos@) = 0.8
Power P = 30kW = 30000W
Formula for 3phase power P = sqr(3)*V*I*cos@
So Current I = P/sqr(3)*V*cos@

I = 30000/1.732*440*0.8
So Required amper = 49.2 A

Answer / a.bala

30 / Rt3xpfx voltage i KV
30/Rt3 x.8x.440= 49.2 A
Consider starter current 1.2 Time from running current
so 49.2 * 1.2= 59 A
sO you will selecte cable and breaker for 60 A.

Answer / ramya

MR bala i con't understand your answer at(30/Rt3 x.8x.440=
49.2 A)
plz clear me this equvation

Answer / ramya

THANKS MR.BALA

Answer / sidhu.k

Mr, bala your answer is correct i dont repeat it
again,thank you, i think ramyas dout is clear.

Answer / ramendra shukla

Hi Dinesh you are correct but you have made a mistake- in
place of sqr(3) there will be root squre(3)

so Power,P = under root(3) VI Cos@

or P = 1.732 VI cos@

then you are correct while your calculation are correct.

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