This is the coefficent $M_0$ used for calculating cable partial transient temperature rise acc. to IEC 60853-2.

Symbol
$M_{\mathrm{0}}$
Unit
s
Formulae
$0.5 Q_{\mathrm{A}} \left(T_{\mathrm{A}} + T_{\mathrm{B}}\right) + 0.5 Q_{\mathrm{B}} T_{\mathrm{B}}$
Related
$Q_{\mathrm{A}}$