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Re: Getting more input power
Original poster: Esondrmn-at-aol-dot-com
In a message dated 1/6/04 12:28:02 PM Pacific Standard Time,
>Original poster: dave pierson <davep-at-quik-dot-com>
> >3 Phase: each phase 120 degrees apart from each other.
> >2 Phase: each phase 180 degrees apart from each other.
> If you are/were Nikola Tesla inventing 2 phase
> it was two phases at 90 degrees.
> (he later switched to 3 phase/120 degree...)
> Granted, this is obsolete, however this is the
> _tesla_ list.
Very true. In fact the book Empires of Light which I am almost finished
with says the Niagra Falls plant was designed with AC dynamos as you
describe. The Scottish engineer, Forbes, that was in charge of the
original design wanted to go with single phase running at 16 2/3
cycles. The Westinghouse engineers would not agree and they eventually
settled on two phase running at 25 cycles. I believe this is how the first
two 5,000 H.P. dynamos were built. The common Westinghouse system used
elsewhere at that time was 60 cycles for lighting and 30 cycles for the AC
motors. The AC power and distribution systems were built by many companies
and used for several years with no AC motor available, thus just for
lighting. The DC companies still had an advantage because they had DC
motors. If I remember correctly last night's reading, at the time of the
Niagra contracts (about 1893), there were about 200 DC central power
stations installed at the time and about 2,000 AC systems. The
Westinghouse systems had previously used 133 cycles. Their engingeers
spend a couple of years trying to get Tesla's AC polyphase motors to run at
133 cycles even though Tesla told them they need to get it down to 60
cycles. They just did not want to have to replace the generators in all
their installed systems, which they eventually did.