Michael Jones wrote: > My mill seems to be working OK, with decent speeds and feeds - though > I'm getting intermittent missed steps on the fast rapids. I'm still > kind of fixated on making these motors do their best - maybe I'm just > tilting at windmills, who knows. > > I just located some specs on what I believe to be the motor and > control setup on my mill. It appears to be a Vexta PH266 series > motor with Thompson L6203 driver chips. > > I don't know exactly what I am looking at here and if or how these > values combine into what EMC needs to optimize step length and timing. > > > Current: 0.6A/phase > Voltage: 12 V > Resistance: 20 ohm/phase > Ugh! You are sunk! These are very high resistance and inductance motors. They were designed for use in floppy drives and such, and the current limiting resistor is the motor winding itself. They will perform quite poorly, and can only do a couple hundred RPM at best. Motors designed to give good performance will have resistances of 1-2 Ohms, and voltage at rated current of just a couple volts. These motors work VASTLY better even with mediocre drivers like the L6203, and can deliver usable torque at over 1000 RPM with a good driver like a Gecko.
Step timing has to be right for the driver to function correctly, but you are not going to improve perfomance by tweaking the step timing. Jon ------------------------------------------------------------------------------ Crystal Reports - New Free Runtime and 30 Day Trial Check out the new simplified licensing option that enables unlimited royalty-free distribution of the report engine for externally facing server and web deployment. http://p.sf.net/sfu/businessobjects _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
