Semi-OT: Crazy half-baked phase conversion question

Here's a generator head that I sold a long time ago. It can be reconnected from 3 phase to single phase. It has 12 leads.

So, you are right, such reconnectable heads do exist, however if the head is not reconnectable, the OP is screwed.

After some thinking, I think that the best route for a practically minded man it to look hard and long for a 3 phase supplied UPS that produces single phase power.

Such things do exist, usually no one wants them, most sellers want unrealistic prices for them (and never sell anything), but you can find something for next to nothing if you look hard enough.

i

one a simple center-tapped autotransformer, which can be set up by the proper wiring of a step-down transformer. The other one, however, needs to be a 0.86 : 1 ratio transformer, which might be made from a tapped voltage-adjusting transformer. The Scott-Tee converts 3-phase to single-phase and vce-versa with no losses or problems. 20 KW, however, will be a pretty big setup.

Jon

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I thought that a Scott-T was to convert between three-phase and the rather uncommon two-phase which some old equipment used.

Enjoy, DoN.

Ask your local power company for some guidance. They might be able to provide you with an old power pole transformer (or tell you where to get one) as they have old stuff sitting around all the time. I don't know if they put old transformers back into service, but you might be able to score something that will work for you.

Thanks! Hadn't even thought of them.

The Scott-Tee was indeed used for converting two-phase to three-phase. It was used in power plants in upstate New York where the alternators were two phase. I believe it has been used more recently (and may still be) in converting from synchro to selsyn and vice versa in servo systems.

You have three phases - that is nice. You only need one for the house. If your primary was this one it would induce a field . Then the secondary is a wire.

Take a wire - fold it in half - and then with it - feed the folded end in and around and around. The folded end is the common or neutral. Each end turns out to be 180 degrees out of phase.

This is an electrical phase thing - not a mechanical phase thing. IIWY - I'd buy a 240v to 120 0 120 transformer.

Good luck, Martin Martin Eastburn @ home at Lions' Lair with our computer lionslair at consolidated dot net NRA LOH & Endowment Member NRA Second Amendment Task Force Charter Founder

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