On Wed, 23 Jul 2008 00:57:41 -0500, Jon Elson
wrote:

snip
Humpf! Now, I did see a big compressor, once. It was an
Ingersoll-Rand, single cylinder, horizontal, run by a 300 Hp
salient-pole synchronous motor. They used the synchronous motor
to adjust power factor for the whole plant. (aside: Putting a
synchronous motor on line and overexciting the rotor winding
causes it to draw a leading power factor from the mains, just
like a huge capacitor bank. They hook a phase angle meter to a
field current controller and it keeps the plant at near-perfect
power factor. This was called a synchronous condenser back in
the old days.)

There were actually two of these in a room in the Emerson
Electric defense plant built in 1951 or so.

The biggest one I've come across had a rated output of 5000
Hp. Water cooled output and virtually no moving parts.

I've seen part of what's left of it, but sadly this one
isn't working anymore

Google up "Taylor air compressor" in Victoria Michigan if
you are curious. They were highly dependent on the proper
location to be workable

--
Leon Fisk
Grand Rapids MI/Zone 5b
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