Re: VFD's / Skates, Tim & JohnS.

--- In CAD_CAM_EDM_DRO@y..., "johnhe" <johnhe@s...> wrote:

> Because the spindle motor is meant to take 415V 3 phase. A 230v

supply is

> almost half that. Am I missing some blindingly obvious point that

means a

> single phase 230v inverter would work on the 415v motor?

Yes, Yes Yes and yes again.
440volt at 3 amp is the same as 220v at 6 amp.
repeated in case you missed it:-
440volt at 3 amp is the same as 220v at 6 amp.
So you put 240 single in and get 240 three out but at a higher
amperage.
To get your 440v motor to work on 220v you change the terminal
connections from star to delta. In star the voltage has to go
through two coils that are rated at 220v hence 440v supply.
In Delta only one coil is connected hence 220v.

>I thought the
> inverter only changed the frequency of the current, not the

voltage. Boston

> Ficor said that most 3 phase motors that work on 460v are

reconfigurable to

> run on 230v 3 phase. Is this what you mean?

Yes you are getting it. Invertors change the frequency but they are
also capable of putting out the amps required to run on 220v

>I have to do all this wallying
> because I don't have the money to make any £300 mistakes, I'm also
> electrically retarded when it comes to VFD's. : )

That's why people who have gone this way are giving you the benifit
of their advise and mistakes. They are not doing it so they can smile
as you fall flat on your face.
Most modern motors will change over from Star to Delta. You have to
look for 6 terminals in the box. Older motors have the star point
buried inside the windings.
If you decide to get this machine and the motor will not chance over
I'll GIVE you a bloody motor to stop you whining <bg>

John S