three phase motor info needed

About all that you can do is to reconnect the windings to delta. This means disconnecting the coils at the star point and reconnecting. Consider coils a1-an, b1-bn, c1-cn where n is the neutral and a1,b1 and c1 are tied to the hot leads a,b,c\ then connect a1 and cn to a, an and b1 to b, bn and c1 to c If rotation is wrong, reverse one coil. The new voltage rating will be 219 to240V. You will be at or below the rated range so will have some derating -say 2 HP at a marginally slower speed.

What you need is a 3 phase rotary power converter rated at 2.5 to 5kw. If you search on Ebay you might be able to find one. These are commonly used in rural mountaintop locations where FM Broadcast transmitters require 3 phase power. Usually they are made for 24 hour operation and are very efficient. In the US these items are usually 240 volts input single phase and 208 or 240 volts output 3 phase at 60 herts. If you can find one that has an input of 240 volts and a 3 phase wye output at

400 volts and 50 hertz you will be all set. Google 3 phase rotary power converters. You will need to make sure the output of the converter matches up properly to your wye connections of your lathe motor. I hope this helps you.

Dick R Broadcast Engineering Consultant

----------- Added comment - what I missed saying is that by connecting delta at the lower voltage - the line current will increase to 173% of that for a star at the same power. This affects breakers and wiring but you would have to check this.

No, at 2kW, you can buy a 240V VFD and most brands will accept a 1 phase input yet provide a 3 phase output without derating. You will still need to reconnect the motor in Delta as someone else pointed out however.