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Q$2$

Calculate the sate of three core XLPL insulated copper cable required to:

$(5$ marks$)$

Supply a $2\mathrm{.}5$ MVA $11$ kV transformer from a utility supply which is $5$ km away

$11$ kV $3-$core XupE$-$insulated copper cable is to be used.

The depth of burial of the cable is $1\mathrm{.}25$ m $.$ Ground thermal resistance is $2K\frac{m}{W}.$ The ground temperature is $25C.$ There are no other cables in the trench.

Short$-$circuit level is assumed to be $150$ MVA $,$ consider the fault will be cleared in half a second.

Use the derated value of current for voltage drop calculations.

Ensure the chosen size meets the voltage drop limit of $5\%.$

De$-$rating factor for depth of burial at $1\mathrm{.}25$ m is $0\mathrm{.}96.($Section $3\mathrm{.}8.$ in DEE$\_$DEEPCA$609\_$Readings$\_$v$2)$

De$-$rating factor for soil thermal resistivity at $2K\frac{m}{W}$ is $0\mathrm{.}84.$

De$-$rating factor for ground temperature of $25C$ is $1\mathrm{.}00.$

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Note: You can use the data from the cable table below or any other source $($manufacturers data sheet$).$ Please supply the manufacturer data sheet with your answer if you are using another source.

$\backslash$table$[[$Copper Conductors$],[\backslash$table$[[$Cable$],[$size$],[($min$\text{'})]],$Current rating $($er ound$)($A$),\backslash$table$[[$Impedance$],[(\frac{}{k}m)$