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Re: 3-phase current - you don't need caps or ider motors!
Hi Bert, all:
There are two problems with the Scott connection. First, you need special
transformers. (Ok, we could wind them...). Second, you need *2* phase
power. I don't think there's any place left, at least not in the US, that
uses 2 Phase power! In a 2 phase system, the two phases are 90 deg out of
phase. This is not the same as the two hot legs in our normal single phase
system, which are 180 deg out of phase, nor the same as two phases of a 3
phase system, which are 120 deg out of phase. 2 Phase is an obsolete
(AFAIK) system that lost out to 3 phase many years ago.
Sorry,
Mike
> 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
>