George,
I seems like I discussed this on another forum some time back and suggested that, if this is not already clearly included in the current code it should be added.
When it comes down to it an ungrounded delta can be so dangerous I can't believe that the NEC hasn't addressed the issue. Personally I feel strongly that some type of ground detection should be required and that a qualified person be available to address a ground detection issue. I don't think it should be screwed around with.
The NEC is specific on so many things it is interesting why they appear to be avoiding this application. Maybe it's simply a political issue.
