The last time I did the 240 volt corner grounded delta system I know the code do required to be white however I did change to grey to indentify a corner grounded and my inspector approved after I gave him a head up why in first place.

Otherwise what I do is put a band on it as well to warn anyone else that print is say " Corner grounded conductor " that will give them a head up.

Merci.
Marc

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