Impedance of sheath outer surface

Definition according to Cigré guide 531 chapter 4.2.1, analogue to screen.

Symbol
$z_{sh,o}$
Unit
$\Omega$/m
Formulae
$\frac{m_{e45} \rho_{sh}}{2\pi r_{e5}} \operatorname{coth}\left(m_{e45} \left(r_{e5}-r_{e4}\right)\right)-\frac{\rho_{sh}}{2\pi r_{e5} \left(r_{e4}+r_{e5}\right)}$
Used in