Impedance of screen outer surface

Definition according to Cigré guide 531 chapter 4.2.1, parameter $z_5$.

Symbol
$z_{sc,o}$
Unit
$\Omega$/m
Formulae
$\frac{m_{e23} \rho_{sc}}{2\pi r_{e3}} \operatorname{coth}\left(m_{e23} \left(r_{e3}-r_{e2}\right)\right)-\frac{\rho_{sc}}{2\pi r_{e3} \left(r_{e2}+r_{e3}\right)}$
Used in
$z_{e4}$