> -----Original Message-----
>
> I totally agreed with Eric on this. The newer speed control phase
> converters (what is their real name?)
Variable frequency drives.
It will obviously vary by location, but when I looked into 3ph power for a
small business several years ago, it would've cost many $1000 for the
service (even though there was 3-phase power on the pole), and the minimum
monthly charge was something like $250.
The homebrew converters that someone mentioned are just a 3-ph 'idler' motor
and some big capacitors. We're talking under $100 if you're a good
scrounger. Not quite as good as a 3-ph supply, but with careful tuning
(capacitor selection), you can get 80-90% of the normal power output. Since
most 3ph motors are very conservatively rated, this usually means you can
get 100% of the nameplate power without overheating.
I haven't looked for homebrew plans for a VFD, but I'll bet it's possible
for something like $100-200/hp using modern transistors.
Randall
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