On Tuesday 28 May 2024 01:49:52 pm Paul M Foster wrote: > I've never see a 3 phase in a house. Common in commercial/industrial, > though. Residential installations (talking in the US here) typically involve *one* transformer tapping a single phase out of the three that are up there on the pole. The secondary is center-tapped, and it's that point which is grounded at the service entrance. Running 3-phase power requires *three* transformers up on the pole, much more in the way of expense if you want that for some reason, and I don't know of anybody that does that. Even those who are into having some nontrivial machinery around seem these days to use a VFD to give them multiple phases at the machine, rather than going through the expense of having it run in from the pole...
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