Re: [CAD_CAM_EDM_DRO] Captain Nema Nemo

info.host@... wrote:

> > What you want is a VFD (Variable Frequency Drive). With this, you will
> > not need the motor starter or the phase converter. 3 Phase motors are
> > usually cheaper than single phase, and also generally perform better.
>
> How much do VDF's cost in the 2-3hp range? The man said he couldn't promise
> me the spindle motor works as he hasn't plugged the mill in yet. I thought
> it might be easier to renew the spindle motor anyway because it must have
> worn a bit by now. If it's triple phase I can start the spindle on my single
> phase using the capacitor over two phases idea but 415V? Any thoughts? I
> could ask him to try it if he has triple 415v, whether he will or not I
> don't know.

Most machine tool motors are dual voltage, 208-230 or 440 V, by switching
some wires in the junction box. VFDs are available in the $150 - 250 range
in the US, seems the market is flooded with them, now. In fact, a 440 V
VFD is probably cheaper than a 220 V unit, as fewer people want to deal
with the higher voltages. You could use an autotransformer or step-down
transformer (backwards) to produce the 440 V to run a 440 V VFD.

Finding a replacement motor with the correct shaft dimensions and mounting
arrangement may prove difficult! Yes, you could use a phase converter
arrangement to test the motor. Some work well on single phase, some
don't.

Jon