Calculation — Formula For Cable Size

For a , the approximate voltage drop ($V_d$) is:

However, the rated ampacity ($I_{rated}$) of a cable depends on several correction factors. The practical formula for selecting a cable based on heating is: formula for cable size calculation

$$ I_{table} \ge \frac{I_{load}}{k_1 \times k_2 \times k_3 \times \dots} $$ For a , the approximate voltage drop ($V_d$)

A more accurate form for incorporates reactance ($X$): formula for cable size calculation

$$ A = \frac{2 \times \rho \times L \times I}{V_{drop_allowed}} $$