For cables, the negative sequence impedance $Z_{neg}$ is equal to the positive sequence impedance $Z_{pos}$.

Symbol
$Z_{\mathrm{pos}}$
Unit
Ω/m
Formulae
$R + 1.0 i X_{\mathrm{c}}$
$X_{\mathrm{c}}$
Used in
$Y$
$Z_{\mathrm{neg}}$