gene heskett wrote: > My gut reaction to that Jon, is that it would total the amps by turning > into a very low impedance load at the target frequency. > No, that is why you put resistors in series with either the cap or the parallel LC. My understanding is that the resistors could be a fairly high value, maybe 100 Ohms or so. This would be a load of maybe half an amp per phase on typical drives. The drives are current-limited. But, putting a cap directly across the motor output of the drives would cause damage for sure. > The usual fix, and what I use, is a combination of microstepping to reduce > the amplitude of the step size to something that doesn't excite the > mechanics so much, and the damper on the back of the motor. I have > switched to 4 step from 8 for test, and this problem is much much worse at > 4 steps compared to 8. > > The new amps I have coming claim to be able to do 64 step microstepping. > Whether that is an exploitable advantage remains to be seen cuz they're > still on a row boat. > Microstepping is a HUGE improvement over full- and half-step drives, the difference in many cases is completely amazing. I agree with Mariss Freimanis at Gecko that there is little benefit in going above 10X microstepping. A gecko drive with the "damping" adjustment pot set right for the motor is QUITE good. Very little humming and no sign of resonance.
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