Am Freitag, dem 22.11.2024 um 10:46 +0200 schrieb Viesturs Lācis: > Robert I was hoping that your experience might help on this as I am > getting something that I have not seen before - with pwmgen value = 0 > there are 0.3V on the actual analog output (that is approximately > 1/30 > of the full range so should give about 10Hz on VFD output as I have > 0-300Hz range specified in Pr0 and Pr1) but the VFD runs the motor at > much higher speed - the frequency matches Prc parameter in VFD. > Increasing analog ooutput voltage gradually increases the speed so > that 10V gets me 300Hz which is expected. If I change Prc parameter > the min frequency also changes but the problem is that setting it to > 100 or below does not work properly (although default value is 50 > according to manual). Here is a little video: > https://www.youtube.com/watch?v=bOSE56Y3TI8
Something is probably off with your electrical setup and/or your configuration. that's in my config (7i93 / 7i48): # When used with HostMot2 firmware, the PWM generators should be set # for UP/DOWN mode (mode 2) and the PWM frequency set for 24 KHz setp hm2_7i93.0.pwmgen.pwm_frequency 24000 setp hm2_7i93.0.pwmgen.05.output-type 2 setp hm2_7i93.0.pwmgen.05.scale [SPINDLE_9]OUTPUT_SCALE # 24000 7i36 should be mode 1, offset mode flag true, 48kHz. I don't think that mesa card can't go below 0.3V. I would * measure mesa output voltages without anything connected * try VFD with shorted terminals 4 / 5 (should run an frequ Pr0) * check grounding * here, terminals 7 and 8 are not connected Also check with potentiometer instead of voltage signal. My VFD will go as low as you want, even so far that the motor won't turn. I have got min frequ / Pr0 = 0Hz, max frequ / Pr1 = 400Hz and Prc which is the trip point between V/f=const to P=const at 300Hz. Spindle motor is specd for 350V constant between 300Hz and 400Hz equiv. to 18000 and 24000 U/min at 9HP. (max power accordingly lower at lower frequency, should be 4.5HP at 9000 U/min and 2.25HP at 4500 U/min) If your spindle motor is built for 300Hz/18000rpm or 400Hz/24000 rpm you should set Prc to 300Hz. Check b14. Prc has to be at least 1/16 of the second value of b14. for reference my parameter settings: Pr 0 0 Pr 1 400 Pr 2 5.0 Pr 3 8.0 Pr 4 125 Pr 5 100 Pr 6 5.1 Pr 7 4.8 Pr 8 150 Pr c 300 b14 PWM 11.7 / ULF 480 hope that helps Robert _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
