# Factor $h_1$ for emergency load

This factor $h_1$ is used to calculate $I_2$.

It is the factor between the constant current applied to the cable prior to the emergency loading $I_1$ (= $I_c$) to the sustained (100% load factor) rated current $I_R$ for the conductor to attain, but not exceed, the standard maximum permissible temperature $\theta_{max}$.

Symbol
$h_1$
Formulae
$\frac{I_1}{I_R}$
Related
$I_R$
$\theta_{max}$
Used in
$I_2$