Earth conductor

Ground conductor calculation

Earth fault current

\[ I^2 \cdot \frac{t_F}{\ln \left( \dfrac{\theta_F + \beta}{\theta_I + \beta} \right) } = K^2 · S^2 \]

· I: Admissible current, A

· S: Grounding conductor cross-section, mm²

· t_F: Fault current duration (less than 5 s), s

· θ_I: Initial temperatura earth conductor, ºC

· θ_F: Final temperatura earth conductor, ºC

· K: Constant (depends on the conductor material), A·s

· β: It is the reciprocal of the temperature coefficient of the conductor resistance to 0ºC