Substitution coefficient $\beta_1$ for eddy-currents

Symbol
$\beta_1$
Formulas
$\sqrt{\frac{4\pi \omega}{{10}^7\rho_{sh}}}$Cables, $\rho_{sh}$ at operating temperature
$\sqrt{\frac{4\pi \omega}{{10}^7\rho_{encl}}}$PAC/GIL