Mutual impedance shield

Definition according to CIGRE TB 531 chap. 4.2.1

Symbol
$\mathcal{Z}_4$
Unit
$\Omega$/m
Formulas
$\mathcal{Z}_{4,sc}$screen
$\mathcal{Z}_{4,sh}$sheath
$\frac{\mathcal{Z}_{4,sc} \mathcal{Z}_{4,sh}}{\mathcal{Z}_{5,sc}+\mathcal{Z}_6+\mathcal{Z}_{3,sh}}$composite screen and sheath
Related
$\mathcal{Z}_{3,sh}$
$\mathcal{Z}_{4,sc}$
$\mathcal{Z}_{4,sh}$
$\mathcal{Z}_{5,sc}$
$\mathcal{Z}_6$
Used in
$\mathcal{Z}_{cc}$
Impedance conductor [$\Omega$/m]
$\mathcal{Z}_{cs}$