On Friday 27 October 2017 15:43:35 andy pugh wrote: > On 27 October 2017 at 19:30, Gene Heskett <ghesk...@shentel.net> wrote: > > That crossed my mind too, but what difference does that actually > > make? Is there a url that would explain that? > > https://en.wikipedia.org/wiki/Commutator_(electric)#The_commutating_pl >ane
Thank you Andy, that explains it quite nicely. This "field dragging" I have to assume applies even at locked rotor conditions. So the best I can do is bang it even harder when in reverse, up to the the current limit imposed by the pwm-servo setting, about 15 amps. 10 amp rated motor IIRC from reading its label. Interesting in that its a physical limitation only fixable by having a set of brushes for each direction. And that is not about to happen in a $100 - $200 motor, economics sets that rule... Someday, and I live that long, a vfd & a 3 hp motor. But for rigid tapping, this has at least a 20x faster turnaround time at the end of the down stroke. And if I ever get the pid really tuned, even faster. Playing earlier this week, while awaiting parts for the transmitter, overshoot in low gear was an even full turn at around 185 revs. What I'd really like to do is change out the 2/1 gears for 4/1. Not having opened it up, I've no clue if Boston Gear can make that recipe. Yup, people in hell are expecting ice water too... ;-) Thanks Andy. I've an explanation that fits the observation. Cheers, Gene Heskett -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) Genes Web page <http://geneslinuxbox.net:6309/gene> ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
