Sam Sokolik schrieb: > My only question would be - how are the stepper drives shut off? Is the > power removed from them?
The stepper driver itself is not shut down. Only the reference voltage (which stears the output current) is lowered to approx. 10% of the original reference voltage. > When they turn back on - will they be at the right phase sequence as > when they where shut off? You could be as much as 4 full > steps off if I am thinking correctly. Nope, not with the controller board we use. It just lowers the output current a lot. Even with amp-enable-out not connected to the controller board, you could still make the steppers turn (though only very slowly). regards, Sven > ----- Original Message ----- > From: "Sven Mueller" <[EMAIL PROTECTED]> > To: "Enhanced Machine Controller (EMC)" <emc-users@lists.sourceforge.net> > Sent: Wednesday, August 15, 2007 3:31 PM > Subject: [Emc-users] Real amp-enable? > > >> Hi. >> >> Due to the way our machine drives the axes, we would like to turn off >> the amplpifiers when no axis moves (even when the spindle is on), since >> the steppers get really hot if they don't move but are driven at full >> current. >> >> However, axis.*.amp-enable-out goes true as soon as the machine is >> enabled in EMC. Is there any pin for the axes which only gets enabled >> shortly before the respective axis starts moving and gets disabled again >> when it stopped moving? Or any other way we could emulate that behaviour >> with the latest released emc version? >> >> In my opinion, the current behaviour could easily be emulated if >> axis.*.amp-enable-out would go true only under the above condition if a >> pin iocontrol.emc-machine-on would be added. >> >> Alternatively (so as not to break old installs), adding a pin >> axis.*.enable-movement (possibly under a different name) would surely >> work just as well. >> >> On a different topic: >> >> Also, our controller supports a "boost" option. This increases the >> current on the steppers to gain some torque at high speeds and/or high >> accelleration. We don't really need it, since our use of the machine >> doesn't care to much about speed, but support for this would really be >> nice in the future (we plan on building a new machine from scratch once >> we got the current one working nicely with EMC), but using boost needs >> some thinking. For example it can't be used for too long, since it might >> heat the steppers up too much, so its usage would need to be tracked in >> the motion planner I think, since it needs to slow down >> movement/accelleration if the boost had been used too much recently. >> >> Regards, >> Sven >> >> >> ------------------------------------------------------------------------- >> This SF.net email is sponsored by: Splunk Inc. >> Still grepping through log files to find problems? Stop. >> Now Search log events and configuration files using AJAX and a browser. >> Download your FREE copy of Splunk now >> http://get.splunk.com/ >> _______________________________________________ >> Emc-users mailing list >> Emc-users@lists.sourceforge.net >> https://lists.sourceforge.net/lists/listinfo/emc-users > > > ------------------------------------------------------------------------- > This SF.net email is sponsored by: Splunk Inc. > Still grepping through log files to find problems? Stop. > Now Search log events and configuration files using AJAX and a browser. > Download your FREE copy of Splunk now >> http://get.splunk.com/ > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users ------------------------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Still grepping through log files to find problems? Stop. Now Search log events and configuration files using AJAX and a browser. Download your FREE copy of Splunk now >> http://get.splunk.com/ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
