It is the factor between the resulting emergency load current $I_2$ and the sustained (100% load factor) rated current $I_R$.

The method for calculation of emergency rating $I_2$ only holds for values of $h_2$ ≤ 2.5.

Symbol
$h_{\mathrm{2}}$
Unit
-
Formulae
$\frac{I_{\mathrm{2}}}{I_{\mathrm{R}}}$
Related
$I_{\mathrm{2}}$