What will be cable size & CB rating for 50KW motor at 30m distance from panel?

Question

Accepted Answer

The cable size and circuit breaker rating for a 50KW motor at 30m distance from the panel depend on factors like voltage, current, and installation conditions.

Calculate the full load current (FLC) of the motor using the formula: FLC = (Power (kW) * 1000) / (sqrt(3) * Voltage)
Select a cable size based on the FLC, voltage drop considerations, and installation conditions
Choose a circuit breaker rating based on the FLC and the motor's starting current requirements
Consider factors like ambient temperature, cable grouping, and installation method when determining the cable size and circuit breaker rating

Accepted Answer

Zsc = 5% Impedance(Z) of the transformer
Zsc x V^2 / Sn = 0.05 X 400^2 / 1000*1000 = 0.008 Ω
Isc = V / root(3) / Z
Isc = 400 / 1.732

Accepted Answer

As per my knowledge some informations are missing hence I have to assume as follows to get the result. 
50kW, 3 phase, 415V, AC induction motor, operating at a power factor of 0.85
Using the expression P= 1.732*V*i* p.f
Current comes out to be 82A. Considering a de-rating factor of 0.75, the current comes out to be,

i = 82/(0.75)= 110A

So we need to choose a cable size which can safely carry 110A.

Referring to standard cable sizes,

3C*25 sq. mm XLPE armored copper cable or 3C* 25 sq. mm XLPE armored aluminium cable.

Kindly note that, for motors, it is a common practice to use 3 core cables.

This is the cable size provided the the distance between the panel and the motor is such that voltage drop is less than 4% of system voltage. if voltage drop exceeds a given value, the next higher size of the cable has to be used.

What will be cable size & CB rating for 50KW motor at 30m distance from panel?

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What will be cable size &amp; CB rating for 50KW motor at 30m distance from panel?

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What will be cable size & CB rating for 50KW motor at 30m distance from panel?