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*. ------------------------------------------------------------------------------ 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
