Interesting discussion. Karl T I'm not sure I understand your description. Gar is correct, at your main panel, your neutral should be bonded to an earth ground. Neutral in a single phase system is current carrying. Safety ground shouldn't be.
Thats the whole reason for a 3 wire system. Think of it this way, if the neutral at the machine was tied to the machine frame, not safety ground and the neutral opend up, your machine frame when on would be at 120V. The reason you switch and fuse the hot side at the box.
Phil, Still too many interests, too many projects, and not enough time!!!!!!!!
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