On 8/26/2015 3:48 PM, Christian Kennedy wrote: > > On 8/26/15 12:33, Paul Koning wrote: > >> 90? Three phase power is 120 degrees apart, center-tapped "two >> phase" home power is 180 degrees, but I don't know of any power >> company service that produces 90 degree shifts. > > There's a bunch of 90-degree two-phase stuff in Philadelphia; in > particular the city center has a lot of buildings that are fed 90-degree > two-phase from PECO. I suspect (but do not actually know) that PECO > derives two-phase from three-phase using Scott-T transformers. > >
Man, sometimes one can be right by accident! (I did really mean to say 120 degrees, originally). JRJ
