Answer / vaibhav v t

You can use 3 core x 1.5 sqmm copper cable.Upto 5 hp three
phase or single phase your can use this cable.

Answer / abokamal

cable design.
first we have to choose CB.
(I)load=P/(V*PF)......... assume pf=0.8
(I)=746/(230*0.8)=4.1 Ampere
(I)cb=(I)load *s.f (FASETY FACTOR)=4.1*1.25=5.1 Ampere
(I)cable=(I)cb/D.F (DERATING FACTOR)=5.1/0.8=6.33 Ampere
from catalouge you can select the cable according to the
current.
you have to see (volt/ampere/meter) to see the voltage drop
limit which according to +-5%

Answer / kumar

Mr.vaibhav your answer is standard or you find out by using
formula ?

Answer / vipin

kamal is right ,after deciding the load current you ll have to consider the starting condition....
as per the IEEE regulations you ll have to consider 3 to 4 times the rated current as the starting current...as the rated current is coming around 6 amperes you can select a CB of 20A DP or SP. A 4sqmm cable will be std for the 1 hp pump.. you will have to verify with your supply company rules for the size of cable to be used for the designed value of circuit breaker.

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