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Re: 3-phase current - you don't need caps or ider motors!



"I knew I had this somewhere, but it took me a while to find it.  There
is a
way 
to change 2 phase power to 3 phase using only two transformers!  It is 
called a Scott transformer, and was used by power companies to go from 2 
phase to 3 phase or 3 phase to 2 phase power.  You do not have the puny 
power limitations of capacitor systems, nor do you have to use a large 
motor/generator setup.  I found this in my 1939 Coyne home electrial 
course.  One transformer is centertapped, the other transformer has a
tap 
placed at the 86.6% point.  I will place the schematic and text on my
web 
page in the next day or two and I will notify the list when it's there.
This is 
such a handy thing for high-power coilers to know how to do.

Bert Pool"

	IF you already have a two-phase power source, and I am not aware of any
in use these days, you can use the Scott Tee to covert from two phase to
three phase, and vice versa.  Trick is getting the two-phase power
source to begin with.  We're talking about single-phase power here, and
there isn't any practical way to convert reasonable amounts of power to
three phase with a static device.  For small currents a capacitor phase
shifter, or better a capacitor-inductor phase shifter, will work.

Ed