Inductance $H_3$ armour

3rd component of inductance due to armour steel wires.
For non-touching wires, $H_3$ is zero.

Symbol
$H_{3}$
Unit
H/m
Formulas
$0.4\left(\mu_{t} {cos\left(\phi_{ar}\right)}^2-1\right) \frac{d_{f}}{d_{ar}}{\cdot}{10}^{-6}$
Used in
$B_{1}$