Re: [CAD_CAM_EDM_DRO] How do you compare steppers to servos

OOPS, A PS:
Mariss recommends designing to a max of 80% of rated rpm on a servo
motor so change that to 80%*3000 or 2400 rpm and then divide by that
by 750 or 3.2 ratio.

Art
AKA Country Bubba



At 12:17 PM 2/25/2011, you wrote:

>IF you want to match the torque speed characteristics of the stepper
>system, find the torque curve for that stepper motor.
>At the max rpm of the stepper, note the torque it will produce at
>this working point. The holding torque is relatively useless for
>figuring useable torque at speed.
>
>Now, you have the basic information you need. It is a balance of
>tradeoffs between torque and speed with the servo. Let us assume the
>max speed of the stepper is 750 rpm. Most servo motors are rated at
>relatively high rpm say 3000. To match the rpm of the stepper, you
>will need a reduction of 3000/750 or 4:1. No take the torque rating
>of the stepper (at speed, not the holding torque) and divide by this
>ration (4) and this will give you the minimum CONTINIOUS torque
>rating you want from your new servo.
> From this, I hope you get the idea and proceed from there.
>
>
>Art
>AKA Country Bubba
>
>
>
>At 12:01 PM 2/25/2011, you wrote:
> >Suppose a system is advertised using nema23 steppers of some size,
> >say 260 oz-in.
> >
> >You want to build the same system but instead use servos.
> >
> >How do you compare the compare power of the the steppers to the servos
> >
> >thanks
> >Glenn
>
>
>
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