Hi Peter, thanks for you reply. > Its hard to tell with motor specifications, sometimes they are RMS and > sometimes they are DC (for example lots of large BLDC motors are rated 320V > which actually means they are 220V AC motors)
I see. I'll stick with 24 V for now, the power supply is a 350 W unit. > 1. initial rotor alignment (if wrong you will have different torque each > direction) I think this is OK, as the motors spin smooth and nice in both directions. > 2. Make sure the deadtime is set to 0 It is set to 0 (line 207 of the hal ini: http://restweiss.de/bldc_1.zip). > 3. Make sure the PWM rate is set fairly high so you dont get current limiting > from ripple current (40KHz is good for 7I39s) PWM frequency (is that PWM rate) is set to 20 kHz, but I tried 40 kHz and it makes no difference. > 4. Make sure you have the 7I39 current limit set to 15A and not 7.5A Current is limited (still default setting) but I don't think this is the problem. Using a clampmeter I measure 600 mA max. at stall. > 5. If you have problems at high speeds, consider running LinuxCNC master and > raising the servo thread rate as high as you can (good MBs can do 4 KHz or > better) (linuxcnc master has a patch to BLDC than extrapolates the > commutation > angle base on velocity so approximately halves the commutation angle > error at high speeds) Oh, that's cool feature, but I only need very low speeds - so no need to switch I guess. What's next to investigate? Greetings Flo ------------------------------------------------------------------------------ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
