This is the loss factor for sheath caused by eddy currents.

For single-core cables with sheaths bonded at both ends (solid bonding) of an electrical section, the loss due to eddy currents can be neglected, except for Milliken conductors. For cables with Milliken conductors, the loss factor should be increased to take account of the loss due to eddy currents in the sheaths.

The eddy-current losses for wire screen and an equalizing tape, or foil screen over the wires are considered negligible (for the screen).

Symbol
$\lambda_{\mathrm{1e}}$
Unit
-
Formulae
$\lambda_{\mathrm{1es}}$single-core cables with single-point- or cross-bonding / multi-core cables with common sheath, without magnetic armour
$F_{\mathrm{e}} \lambda_{\mathrm{1es}}$single-core cables with Milliken conductors and solid bonding / multi-core cables with common sheath and steel tape armour (or other magnetic armour)
$0$single-core cables bonded both sides / multi-core cables with separate sheaths / cables without screen/sheath
Related
$F_{\mathrm{e}}$
$\lambda_{\mathrm{1es}}$
Used in
$\lambda_{\mathrm{1}}$