On Fri, 2009-09-04 at 14:11 -0400, Sean Breheny wrote:
> Note that the tolerances on three phase power seem (in my experience)
> to be wider than typical 120V circuits. I've seen 480V be as high as
> 510 and as low as 460 (about 6% off). Under normal circumstances, I've
> never seen 120V be more than 125V or less than 115V (4% off).

The apartment building I grew up in (which was built in the 60s)
supplied each unit with 2 phases of a 3 phase source. Caused an issue
when getting replacement elements for the oven since most are 220V yet
we only had 208V supplied.

Another consequence is our "120V" outlets varied widely, I vividly
remember my meter on one outlet reading 107V and on another (which was
on the second phase) reading 125V.

This became quite an issue when we upgraded our window air conditioners,
the phase with 107V couldn't cut it, the AC when starting up would trip
it's internal overload (or if not that the fuse would eventually blow).

That building was also my only exposure to alu wiring. I didn't like it,
the alu is "tougher" then copper so to bend 14 gauge you had to pretty
much use pliers, copper I can do easily with my fingers.

TTYL

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