Motora

You don't.

A three-phase motor can only be connected to a three-phase supply.

Not necessarily true - that depends on the HP and voltage - there are many VFD's made that convert 120VAC single phase to 240V three phase - but this only applies to up to 3 HP or so. I haven't found a 5 HP unit yet. I believe there are also 240VAC single phase to 480V three phase, but I haven't used one yet, so I don't know the HP limit on these.

Google "Lenze (AC Tech) SMV(ector)" series. Allen Bradley PowerFlex 4 line also has a 120V unit for 240V three phase.

I didn't know that, I'll look in to that. I had did some work where the grid was only single phase. This would be very useful. Thanks

We use them on the tanks we build with bottom mount mixers. I am having the staff wire one of these almost weekly. I also designed a general purpose VFD center with 5 of these in various HP capabilities for tanks with mixers where the customer will provide a VFD at the plant, but still wants to see the mixer run here at our site.

You learn something new every day.

Thanks.

sure do,

you can hook a single phase motor to 3 phase supply, but you can not hook a 3 phase motor to single phase supply, unless you do this.

use a phase converter.

http://www.phase-a-matic.com/

You can create an artificial 3 phase system. 60 year old technology but it works!

Very good, but I'll bet the AC Tech VFD at less than $200 USD is a cheaper way of doing this.

This is like my college EE project in the mid 1960's where I made a color organ (light box) for 3 sound ranges from the same sort of technology plus a low filter, a range filter and a high filter, because the SCR's were very new then and rather expensive. Yes the old ways still work, but the modern ways are now lower cost.