Re: What makes a motor a servo?

--- In CAD_CAM_EDM_DRO@yahoogroups.com, Jon Elson <elson@p...> wrote:

> Polaraligned wrote:
>
> >So let's see what is going on here:
> >At 300 RPM when the stepper is producing full power of 133W making the
> >deep cut, the servo is making the same cut, at 3000 RPM, and using
> >the same 133W.
> >
> Well, no, the servo would be delivering 1330 W due to the 10 x greater
> speed.
>
> Jon

Well, no Jon. The servo is delivering 60 oz-in and 3000 RPM.
This product divided by 1351 puts 133W at the motor shaft.

I chose 3000 RPM for the servo speed to compare it to the power
put out by the stepper at it's peak. So the servo is putting
out the exact same power as the stepper for that same feedrate
at the table. Hmmmm.....yet there is 10x more power available
at the leadscrew due to the reduction?
I believe Mariss was talking about power at the motor shaft in his
post otherwise his chart for the servo is off by a factor of 10.
That said, would this not make the servos performance 10x more
impressive seeing as though there is 10x more power available
at the leadscrew than in the chart he posted? Isn't power at the
leadscrew what is going to get the work done?


Scott