Re: [CAD_CAM_EDM_DRO] 90v DC motor as servo?

> Chris Stratton wrote:
>
> > Les,
> >
> > Thanks for the info. Obviously, one is not going to build a high
> > speed servo system with 90v DC motors. I do wonder however if a
> > surplus motor of this type plus a G320/340 could be used to build a
> > cheap system with stepper-level performance.
> >
> > I believe the SCR motor develops its rated power at 1750 RPM as
> > opposed to maybe 6000 for the servo. This would mean a lower
> > reduction ratio - possibly direct drive, which would reduce the
> > effective rotor inertia, right? (well really, the rotor wouldn't have
> > to be accelerated to as high a speed)
>
> You should know that any servo system needs an encoder to measure
> position. Some servo amps require a DC tach, too, although the Gecko
> servo drives don't.

Sure does. I have a linear strip encoder half finished for the Z axis
of the lathe. But that wouldn't work very well for a servo motor that
derives velocity from the encoder, so I'd need one on the motor, or an
amp that could use a tach input.

Chris

--
Christopher C. Stratton, stratton@...
Instrument Maker, Horn Player & Engineer
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