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Total loss in shield and magnetic armour

The total loss in shield (screen$||$sheath) and magnetic armour is given acc. IEC 60287-1-1 chapter 2.4.2.1 and is used to calculate the loss factors $\lambda_1$ and $\lambda_2$ which may be assumed to be appoximately equal.

Symbol
$W_{sar}$
Unit
W/m
Formulae
${I_c}^2 R_e \frac{{B_2}^2+{B_1}^2+R_e B_2}{\left(R_e+B_2\right)^2+{B_1}^2}$
Related
$B_1$
Loss coefficient $B_1$ of armour [$\Omega$/m]
$B_2$
Loss coefficient $B_2$ of armour [$\Omega$/m]
$I_c$
Conductor current [A]
$R_e$
Electrical resistance of shield and armour [$\Omega$/m]
Used in
$\lambda_{11}$
Loss factor of shield by circulating currents
$\lambda_2$
Loss factor of armour