Re: [CAD_CAM_EDM_DRO] Thanks - was: Things to check? is now: RUNNING~!

On Thursday 18 September 2003 01:38 am, Tim Goldstein spake:

> > -----Original Message-----
> > Motors got very warm to the touch after a little running.
> > I could grasp a motor, but only for about
> > 10 seconds before it got very uncomfortable.
>
> High over voltages (like you have) yield hot motors even if the current
> is set within limits. Good explanation and graphs in the Gecko stepper
> white paper (a must read). So, if you are sure the current is set
> correctly (you can always reduce it just to try) and you are still
> getting hot fast then you know it is because you pushed the upper limit
> on the over voltage.

But I should be down at 75VDC now with the Variac...
I'll try lower still...

> > Motors *SEEMED* a bit slow for my likes...
> > Is there a way to speed them up?
>
> No. You are already at the voltage limit of the drive. This is assuming
> that you are not running out of pulse from the computer. If you have not
> yet pushed them to the limit step wise where they are stalling then you
> may be able to speed them up by feeding them more pulses.

...can you point me to an approximate point in the docs to explain that?

> > Also, the Z axis motor seemed to be "hunting" all the time.
> > (do steppers need "tuning" also?)
>
> Geckos have a pot for adjusting the midband stabilization. Other than
> that there is not tuning. The motors should lock in at rest and not hunt
> at all.

Intresting.
The Z motor seems to be hunting just slightly.
I'm also getting a very high pitched whine from
one of them, but haven't been able to pinpoint it yet.
(loud shop)

> > What is the "recommended" setting for "steps" in the Geckos?
> > Full, half, or less?
>
> Depends on your machine and computer. 10X multiplied will give you the
> smoothest running as you are the least dependent on the smoothness of
> the controller program pulse stream. But, it also gives the worst
> resolution. 1X gives the highest resolution, but requires the highest
> pulse stream from the computer. You will need to pick a setting such
> that your computer can put out a sufficient pulse stream to drive your
> motors at the speed you want. Depending upon the software and the
> mechanical reduction you sometimes have to balance the setting between
> resolution and speed.

Hmmm...
What is considered "overkill" in processor speed for EMC?

Weyland