Re: [CAD_CAM_EDM_DRO] Re: Max stepper motor speed - rpm
Posted by
Jon Elson
on 2005-08-12 20:54:43 UTC
>--- In CAD_CAM_EDM_DRO@yahoogroups.com, "Scott Riddle" <sariddle@l...>No. Due mostly to iron losses, steppers cannot be run fast for very
>wrote:
>
>
>>Say I start with a Gecko drive that has a freq=200kHz and
>>it is a 10 micro step drive and the motor os 200 steps per rev. Would
>>it be 200,000/(200*10)= 100 revs per second. Times it by 60 to get
>>6,000 RPM. So the drive is capable. Now is the motor.
>>
long. They produce heat roughly proportional to speed. Somewhere around
2000 RPM on mid-size motors, the heat produced exceeds the motor's
heat dissipation capacity. Generally, smaller motors can spin a bit faster
than large motors.
>> Would you justWith good drivers like the Gecko, you can get usable torque up to speeds
>>have to look at the speed torque curves and see for the desired torque
>>what speed you can run at? Is there some way to determine this if you
>>do not know the Mfg of the motor?
>>
the motor
cannot survive for very long. At 6000 RPM, where the available torque will
be VERY small, the motor will self destruct in about 2-3 minutes.
>>You can assume that it is impractical to run steppers much above 1500 RPM
>>My main reason for this question is that I am thinking of buying a
>>stepper that puts out around 600 Oz-in torque and direct couple it to
>>my .200" pitch ball screw. This would give me good speed capabilities
>>when routing on wood. I am trying to avoid to have to add the extra
>>complexity of a belt system.
>>
>>
on large motion control axes. I had a 150 Lb mini-mill with 16 TPI
leadscrews,
and direct-drove it with NEMA size 34 motors. I demoed it at the NAMES show
in 2003 running at 90 IPM. This required the motors to spin at 1440 RPM.
Only by using a hardware system to generate the smoothest trains of step
pulses
could I do this, and the motors got quite hot at this speed.
1500 RPM to a 5 TPI screw (.2" lead) is 300 IPM. 6000 RPM would produce
1200 IPM, but you won't do this with steppers. Do you really need to
move at
1200 IPM? This would cover 8 feet in 4.8 seconds.
Jon
Discussion Thread
Scott Riddle
2005-08-12 11:48:27 UTC
Max stepper motor speed - rpm
JanRwl@A...
2005-08-12 13:54:41 UTC
Re: [CAD_CAM_EDM_DRO] Max stepper motor speed - rpm
Scott Riddle
2005-08-12 14:50:04 UTC
Re: Max stepper motor speed - rpm
caudlet
2005-08-12 15:23:23 UTC
Re: Max stepper motor speed - rpm
John Johnson
2005-08-12 16:54:03 UTC
Re: [CAD_CAM_EDM_DRO] Max stepper motor speed - rpm
Jon Elson
2005-08-12 20:54:43 UTC
Re: [CAD_CAM_EDM_DRO] Re: Max stepper motor speed - rpm
Scott Riddle
2005-08-12 22:16:48 UTC
Re: Max stepper motor speed - rpm
Scott Riddle
2005-08-12 22:40:40 UTC
Re: Max stepper motor speed - rpm
Scott Riddle
2005-08-12 22:51:10 UTC
Re: Max stepper motor speed - rpm
caudlet
2005-08-13 08:06:22 UTC
Re: Max stepper motor speed - rpm
turbulatordude
2005-08-13 09:15:42 UTC
Re: Max stepper motor speed - rpm