Ed Fanta sent me a HUGE Fanuc "red cap" brushless servo motor to work with. These motors use an insane proprietary commutation encoder scheme that puts each cycle of the motor into 16 states, represented by 4 signal lines. Obviously, for a 6-step drive, which I'm pretty sure they must have been using at that time, just using 3 lines would have been a LOT more straightforward, but not proprietary.
Anyway, I have just gotten a converter board partially working for this motor/encoder. The idea is to use the 4 proprietary signals to get the motor moving, and switch to counting encoder pulses once the encoder index pulse (Z) has appeared. I don't have the inital use of the absolute signals aligned right, but once the index is seen, it works very well. Making the absolute signals work is just realigning the code values. But, the good news is this motor runs VERY nicely with my 6-step PWM drive, very smooth and with practically no vibration. So, for anyone considering a retrofit of a machine with brushless Fanuc motors, I should have a solution available very shortly. I will be bringing this to the EMC Fest for demos. 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
