By the way the VFD is set to let the motor run free and I get the following error with a max ferror of about 5 mm so It's definitely something that I'm doing wrong.
Here's Andy's video of the spindle: http://www.youtube.com/watch?v=3oTJNEVpvYY Thanks! 2013/12/4 Leonardo Marsaglia <leonardomarsagli...@gmail.com> > Hello all. > > I managed with your help to put my 6i25 and 7i77 working. > > Now I'm trying to use this to move an induction motor with a C2000 VFD to > make a positioning system. I know that this is not the best because > induction motors have no permanent magent and high inertia but Andy Pugh > made some interesting things with his spindle lathe in servo mode. > > The screw that I need to move belongs to an old positioning system that > used to work with switches to stop, so high accuracy is not required. The > screw has a 8 mm lead, and I'm comfortable with +/- 0,5 of error. My > encoder is 2500 ppr mounted directly on the screw. Now I'm testing the > engine on the air without the screw and what happens is the following: > > I managed to move the motor and do some tests but I can't get rid of the > oscillation from the PID. If I follow the classic way of tunning the > algorithm when I increment P I don't see any oscillation until I disturb > the motor. When that happens I get a really strong vibration and right > after that a following error. What I'm saying is I can't even start to test > my error to decrease it. > > My vfd is configured with +/-10 volts input and the endoer is roughly > attached to the motor but it's quite firm. When I mount it on the screw > it's going to be perfectly installed now is for testing purposes. > > I would like to know please if you can give a hand since you've a lot of > experience with servos, and as I told, I don't need a lot of accuracy, also > these drives are meant to work with AC induction and permanent magnet > motors in this way for positioning. Please let me know if I'm doing > something wrong with the tunning. > > Sorry for the long text but I needed to explain how the machine is going > to work. > > Thanks as always! :) > > -- > *Leonardo Marsaglia*. > -- *Leonardo Marsaglia*. ------------------------------------------------------------------------------ Sponsored by Intel(R) XDK Develop, test and display web and hybrid apps with a single code base. Download it for free now! http://pubads.g.doubleclick.net/gampad/clk?id=111408631&iu=/4140/ostg.clktrk _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
