Re: 3 Phase - again

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

Original poster: "Jim Lux by way of Terry Fritz <twftesla-at-uswest-dot-net>" <jimlux-at-earthlink-dot-net>

If you're willing to pay for it, you can get what you want.  I have an
electrical contractor friend and about a year ago wired a very large (>$1M,
>10,000 sf)  house in West LA with three phase.  The three phase was
primarily used for: HVAC (a/c compressors), pool/spa pumps, lifts for cars
in the garage (vertical stack parking so you can park multiple cars in
limited "front" space. (plus all the usual single phase loads)  Next time I
see him I'll have to ask how many kVA the service was for.

But, in the context of a several million dollar house, $20,000 to bring in 3
phase power is not a big deal.  In the context of a $1000 tesla coiling
project, 20K for 3phase is a huge deal.  My suggestion was that you might be
able to get them to install the 3 phase for a lot less if you manage to
present yourself in a way that the tariffs require them to provide service,
even if it is economically irrational (i.e. make the bizarre rules work for
you...) from their standpoint.

In the case you observed, it might be that it was easier to balance the
loads.

In the shop where I used to work, they had separate single and 3 phase
services (1000 Amp single phase 120-0-120 and 600 Amp 3 phase 240 Delta).
No idea why they built it that way, other than the building is fairly old
(for Los Angeles... built in 50's), and had a succession of tenants.  I
think the sequencing was: single phase service, added three phase some time
later, upgraded single phase service.  They also had a huge 60Hz-50Hz
converter motor generator set to run a bunch of imported sewing machines off
50Hz. It had a 60 Hz synchronous motor and a 50 Hz synchronous generator
interconnected by a big toothed belt and pulleys in 5:6 size ratio.  The
whine from the belt was truly annoying: we called it "satan's siren" when it
was running, and the sound penetrated the entire 50,000 sf building.


----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Saturday, February 03, 2001 9:03 AM
Subject: 3 Phase - again


> 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
>
>
>
>