Hi Richard, yes the problem is terminology and it is not just because many people are abusing words; it’s because? for the last 10 decades there have been people fooling with generators and transformers, creating many many difficult to describe connections, so the ordinary electricity.

I agree with much of your stuff about DC and terminology, but some not-so-good expressions have been ongoing for years

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Re. I am not sure how a three-wire DC system works. ??????I am not sure what you mean, but if you have not looked at 1890’s electric power, you might think there are only 2 wire systems ?but Most people mean something like this

?whether it is a generator or battery ?this is the common configuration of “3-wire” but ?

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The configuration of the typical LV AC system wiring is the same, or “copied” from Edison’s the 3-wire DC system where there is a “middle wire” or “common wire” or “Neutral”, and ?a ?hot positive ?and ?a hot Negative, both, WRT the middle wire, and for AC, there is “a middle wire”, and at the right point in time the AC system has a hot positive ?and hot Negative both, WRT the middle wire. ??You know doubt know this but use different words.

Re. DC does not have phase.? ..agree ?but the term “split phase” in AC implies divided in the MIDDLE … how do you say that for DC ? I agree it is loose words but seems to convey the idea with 2 words. ???????????

Re ?Since AC and DC are quite different I don't see how a DC system could be "copied" for AC. ???Yes, but the configuration was either copied or reinvented to be the same; just keep the wires and change the two DC generators to ?two AC generators and be careful of the “polarity” of the connections.

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This might not be right, but it was my understanding that originally Edison had one 110 volt DC generator with one wire hooked to ground. ??light bulbs limit was 110V or they wouldn’t. When the generator was fully loaded, to feed more customers, he connect another generator but with the positive grounded, so he then had 220v line to line, or 110 to “ground”. I have never seen if the Ground became a “Ground wire” before the 3-wire system began.[Jim must know], but intentional running current in the ground was a problem, and it seems that the solution was to unground most electrical systems for a while so we had grounded neutrals and ungrounded ones. ???AS I have read and Jim said, ?AC grounding took a while, to evolve.? O course the first wires run into earth rods were in the 1754 for lightning ????? and then they invented insulators for the wires so don’t forget that history. And ?the fire insurance?

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