A simple rule anytime you run 1Ø off from 3Ø WYE system is that you have to have netural conductor the same size as phase conductor.

I don't excatally recall how I did that forumla it was a while seice I done that but corret me if I am wrong.,

( L1-L2 ) / N * 30°

I am not sure if that work right due the phase shift affect on it.

A true single phase MWBC will cancel netural current due 180° shift as long L1 - L2 load is the same the netrual current will read zero { not excactally but it will show near 0 on it }

Merci,Marc

Pas de problme,il marche n'est-ce pas?"(No problem, it works doesn't it?)