On Nov 12, 2012, at 5:56 PM, Yishin Li wrote: > On Tue, Nov 13, 2012 at 1:06 AM, Marius Liebenberg > <mar...@mastercut.co.za>wrote: > >> >> I have seen many alternative solutions that all end up being scraped and >> redone to floating head. >> It is my opinion that the only good and maybe better alternative is the >> capacitive sensing THC system. The simpler the solution the lesser the >> troubles:) >> >> The plasma head we worked with is rigid type. We use the torque feedback > of the Z-axis servo motor to decide if it is hitting the plate. We called > it analog probing. It is useful for underwater plasma cutting. Here's the > video: > http://youtu.be/amnozqEhRYE
Very nice. This is a feature of Granite servo drives (http://granitedevices.com/index.php?q=servo-drive-vsd-e). It is called homing to a hard stop. We use it on our plasma machine to home the X and Y axes which are driven by Granite VSD-E drives . We have it torque limit the servo motors and slow the velocity until the axis runs into a door stop (literally) that we placed at the end of travel. When the ferror reaches a settable max it then backs up to the index pulse of the encoders. Very accurate homing, no switches/wiring required. I never thought of using it to do touch off for the torch, but why not? -Tom ------------------------------------------------------------------------------ Monitor your physical, virtual and cloud infrastructure from a single web console. Get in-depth insight into apps, servers, databases, vmware, SAP, cloud infrastructure, etc. Download 30-day Free Trial. Pricing starts from $795 for 25 servers or applications! http://p.sf.net/sfu/zoho_dev2dev_nov _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
