Good morning everyone,

I would like to ask a few questions, hoping that it is not too profane because although I have some little theoretical notion from a practical point of view, I do not have much experience.

I have in my hobby multi-workshop with a single-phase 3 Kw-220 V power supply, different machines driven by three-phase 380 V motors converted with capacitors for 220 V two-phase operation.

Everything works except for a gigantic as ancient (1951) band saw 2.6 Kw that I can’t get running due lack of starting torque in two-phase mode.

To solve this problem I was thinking in using a single-phase 220V/three-phase 380V 3 Kw inverter;

· Will it possibly work?

However, it would be very convenient for me to be able to also operate the other three-phase machines by the same inverter removing the capacitors from the motors and returning them to three-phase operation.

Particularly on an equally old and big wood lathe would be enormously useful the speed adjustment obtainable from the inverter.

At this point I ask myself:

• is it possible to place the inverter 'on the wall' and permanently connect the different three-phase motors using cables from 4 to 20 feet long?

• Is it possible to use more than one motor at the same time?

• Are the inverters usually equipped with self-protection against overloads or am I likely to burn them using in that way?

Finally, a possible advice on what to buy.


Thanks a lot to everyone's attention.

 

Welcome to AAC!
Bear in mind that the start-up surge current of motors is several times the continuous running current specified on the rating plate.
If you tot up the kWs you're going to need a hefty inverter.

• is it possible to place the inverter 'on the wall' and permanently connect the different three-phase motors using cables from 4 to 20 feet long?

I think a more appropriate location might be 'on the floor' . As for the wiring, in principle it should be ok providing it doesn't breach any local regulations.

• Is it possible to use more than one motor at the same time?

Depends on the inverter rating.

• Are the inverters usually equipped with self-protection against overloads

Any self-respecting one of a reputable brand should be, but some anonymous-make temptingly-cheap one advertised online may well not be.