Equivalent diameter of a group of cables

For multiple cables twisted or bound together, a combined diameter circumscribing all cables can be calculated. The resulting value is also approximatively correct for three loose cables in touching trefoil formation.

Symbol
$D_{eq}$
Unit
mm
Formulae
$D_{e}$$N_{c} \leq 1$
$1.65 D_{e}$$N_{c} \leq 2$
$2.15 D_{e}$$N_{c} \leq 3$
$2.5 D_{e}$$N_{c} > 3$
Related
$D_{e}$