Steve, I have a 190 VMC. The non-linearity is caused by the "Milford Electronics" isolation board which is bolted to the Lenze speed controller (on my machine anyway)
I found if I removed that and used the 0-10v direct into the lenze controller the speed was significantly more linear. You MUST use an isolated power supply though for your 0-10v converter. DO NOT be tempted to share the power supply otherwise you will fry your analogue speed controller (I know I have done it!) Does your VMC have a toolchanger? have you implemented that in EMC ? How have you done the front control panel? Hope this helps Simon ----- Original Message ----- From: <[EMAIL PROTECTED]> To: <emc-users@lists.sourceforge.net> Sent: Saturday, September 20, 2008 12:18 PM Subject: [Emc-users] Closed-loop spindle speed control >I read with interest the recent thread on Spindle Speed in the hope it > would answer my question, but it didn't quite get there! > > I'm converting a Boxford 190VMC mill to use EMC. I have everything > basically working but I have been unable to figure out how to get closed > loop control of the spindle speed. The spindle has a 50ppr encoder and > is driven by a variable speed drive that wants a 0-10V signal to span > the range up to 3500rpm. The voltage/speed relationship is quite > non-linear. > > I've hooked up a counter to give me a speed readout via pyvcp. At the > moment I'm driving the spindle open loop using a lookup table > implemented with the linear8 Hal component. > > But how would I implement closed loop speed control? Is there some > documentation I've missed, or can someone give me some pointers please? > > Steve > > -- > > > ------------------------------------------------- > Visit Pipex Business: The homepage for UK Small Businesses > > Go to http://www.pipex.co.uk/business-services > > > ------------------------------------------------------------------------- > This SF.Net email is sponsored by the Moblin Your Move Developer's > challenge > Build the coolest Linux based applications with Moblin SDK & win great > prizes > Grand prize is a trip for two to an Open Source event anywhere in the > world > http://moblin-contest.org/redirect.php?banner_id=100&url=/ > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users ------------------------------------------------------------------------- This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users