My only question would be - how are the stepper drives shut off? Is the power removed from them? 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.
sam ----- 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
