how to calculate size of cable from motor current given and
how to calculate full load current of a induction motor.

Answer Posted / raviteja vaka

First the simple one: IM Full Load Current
I=W/root(3)*V(L-L)*PF*Efficiency of Motor

PF and Efficiency will be available from name plate data of
IM. In general u can consider PF=0.8 and Efficiency=0.85

Ex: FLC of 37 KW motor having 415V, 0.8 pf and efficiency as
0.85

I= 37000/Root(3)*1.732*0.8*0.85
I=75A

For calculating the cable size they are many factors to be
considered
* Load Current
* Voltage Level
* Length
* Voltage Drop
* Temperature Factor
* Grouping Factor

Is This Answer Correct ?    5 Yes 2 No



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