ECN Forum Forums General Topics of the Trade General Discussion Area 3 phase- neutral needed on alternator?

Would this set-up qualify as a separately derived system? If so, Art. 250-30 would apply.

I see Art. 250-20(b) may also apply.

250-21(2) may permit this setup to remain ungrounded if the machines are controlled with electronic inverter drives...

An ingenious solution Mr. Belson! Thumbs up!