On Sat, Dec 26, 2015, at 06:40 PM, Bertho Stultiens wrote: > On 12/27/2015 12:22 AM, John Thornton wrote: > > It's single phase 240v but no neutral, each leg is hot 120v and if > > measured to ground you get 120v. Measured between the two hots you get > > 240v. > > Ah, it is a two-phase system (because you still have a neutral). Each > phase is 180 degrees apart from each other. > > The generation of the two phases comes from a transformer with a > center-tap denoted as neutral N. Is the neutral floating or connected to > earth locally (where it enters the house) or maybe at some farther away > tranformer-station? >
John T has already responded with the specifics of his situation. Some more background on US residential power: The transformer is typically mounted on a pole and serves several houses. The neutral is connected to a ground rod at the base of the pole. There are three wires from the pole to each house - L1, L2, and Neutral (no ground). Each house has a ground rod. The neutral from the transformer, the house ground rod, a connection from the house cold water plumbing (if copper), the neutrals from all the receptacles, and the ground wires from all the receptacles are all tied together at a large bus bar in the main panel. Other than the tie point in the main panel, neutral and ground are kept separated throughout the rest of the building, including through any sub- panels in garages, etc. John Kasunich -- John Kasunich jmkasun...@fastmail.fm ------------------------------------------------------------------------------ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
