Re: 3 Phase - again

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Edward Wingate by way of Terry Fritz <twftesla-at-uswest-dot-net>" <ewing7-at-rochester.rr-dot-com>

Tesla list wrote:
> 
> Original poster: "by way of Terry Fritz <twftesla-at-uswest-dot-net>"
<Tesla729-at-cs-dot-com>
> 
> Hi all,
> 
> I hate to open this thread, but I have a question from a little different
> angle than anyone else came from :-) I've noticed driving thru some
> of the older, but well-kept neighborhoods of my city several fairly
> large homes that were obviously strictly residential, but yet they had
> 3-phase service, and usually they had two seperate electriclal hook-
> ups from the utility. One was single phase and the other was 3-phase.
> I've been noticing this, especially after the discussion on this list about
> 3-ph and I was wondering if anyone had any thoughts on this? I know that
> Jim Lux said that you must have a >10 HP electric motor, or something
> to that affect with PG&E, and I'm sure all local utility companies have
> similar requirements for 3-phase service eligibility. My question is how did
> these residential homes aquire 3-phase service? I didin't notice any large
> shop building near the properties and like I said, the 3-phase hook-up was
> directly to the home. Comments anyone?
> 
> Keeping 'em sparking in Memphis,
> David Rieben

David,

Are you mistaking the older "three separate wire" 240 volt single phase
power feeds to residences for a three phase service? The old
installations used three separate wires as opposed to the new style 240
volt feeds which use a bare neutral twisted together with the two "hot"
leads. Most, but not all, modern three phase services will normally have
4 wires. At least that's the way it is up here in snow covered, wind
whipped upstate New York.

Ed Wingate RATCB