can you not just get inverter?

that's what i did with couple of three phase motors i got from work.

Not a clue as to what mill or motor it is. 415V three phase? 220V three phase? Is it a dual voltage motor? How many horese power (or kW)? What type of starter?

Two speed motor so no you can't use an inverter.

What you can do is get a rewind company to just connect it in delta, use one winding and fit the VFD then you can over speed it if needed on the VFD.

Reason I say get a rewind company to do this is they can do this with their eyes shut but if like most motors it has a connection diagram inside the terminal box post that here and someone will be able to help

Fitting a single phase motor will work but you are then limited to single speed, a VFD will give you variable speed and be much smoother for about the same price.

Where in the UK are you ?

Pretty certain, I do a lot of work for the rewind people and I'll ask the question.

Again where in the UK are you ?

Can you take the cover off the terminal box on the motor and see if there is a wiring diagram inside, often etched on the inside cover, or failing that a shot or two of the terminal block.

Andy, I would suggest talking to a VFD supplier and giving them details of the motor. They may have the solution.

Martin

I suggest you just treat it as a two pole motor connected in delta (also referred to as mesh) then use a VFD inverter. That will give you a max motor speed of 1420 rpm.

John

Edited By Johnboy25 on 25/09/2016 20:49:08

Hello Andy I think you should take the motor to a rewind shop and ask for their opinion and help. The motor is not a run of the mill motor. I think it will have a total of 6 connection which must be configured in the correct manner to ensure NO burner out. If you connect in Delta the 415 volt windings will, via an inverter receive 240 volts. Apparently there are modified inverters which do give out 415 volts. There was a discussion on Home workshop some time ago about modifying inverters apparently its a simple connection. Never need to try it out and haven't got a spare inverter to play with. Anyway,how is your Naerok ? John

If each of the three windings are tapped then why are only six terminal visible? I would have expected to see 3 x 3 so 9 separate connections.

Tappings in a winding are usually there for voltage selection so I dont understand how the motor can be wired for 2 or 4 pole operation. Do you have a link to information on this type of motor.

Ian P