[bluGill]

Most new industrial 3 phase equipment is running from a VFD which gives speed control. 20 years ago 3 phase was used because the power company would supply you 3 phase, and otherwise single phase was used. Today many home washing machines have 3 phase motors, since a VFD is cheap and 3 phase motors have some nice features.

[jacquesm]

And you can now get cheap single-phase to three phase inverters to drive that gear. You won't be running it at full power but a 240V socket will happily drive such an inverter/motor combo at rates that most hobbyists would be more than happy with.

[bluGill]

Single phase to 3 phase inverters are just a different name for VFD. Running a 3 phase VFD on single phase (tieing all 3 phases together) works if you derate the VFD/inverter. An inverter designed for this application should already be rated correctly.

There is no derating the motor when running on a 3 phase VFD/inverter if you have the correct specs for everything. If you are trying to run a bigger motor than any link in the chain it might work so long as you don't try to draw more power from the motor than the weakest link in the chain.

There is a static phase converter which does derate the motor. They are the cheapest way to run 3 phase from single phase, but otherwise don't have much to recommend them. They are NOT inverters.

[jacquesm]

> Running a 3 phase VFD on single phase (tieing all 3 phases together) works if you derate the VFD/inverter.

Interesting, I've never tried that.

Yes, those cap-and-coil based 3 phase 'convertors' are more of a fake 3 phase than the real thing and they will put a lot of stress on one of the three phase windings of the motor and hardly any on the other two.