Gene, The drive is a "closed loop" stepper drive from Steperonline. Here is a link to the doc. https://www.omc-stepperonline.com/index.php?route=product/product/get_file&file=388/CL57T_V4.0.pdf
I've yet to actually power one of these up yet. (Still have a lot more building to do before I'm ready for that.) But I don't think I'm going to be asking too much of them. At this point I'm only hoping for at least 1000rpm from these NEMA23 closed loop stepper motors. (If I can get them to spin faster great, but I won't be upset if they can't do 2000rpm.) Todd Zuercher P. Graham Dunn Inc. 630 Henry Street Dalton, Ohio 44618 Phone: (330)828-2105ext. 2031 -----Original Message----- From: gene heskett <ghesk...@shentel.net> Sent: Wednesday, October 25, 2023 11:17 AM To: emc-users@lists.sourceforge.net Subject: Re: [Emc-users] Mesa Step Pulses? [EXTERNAL EMAIL] Be sure links are safe. On 10/25/23 08:24, Todd Zuercher wrote: > Hello, > > It is my understanding that the step pulses generated by Mesa cards are > always the minimum pulse length set by for example > hm2_5i25.0.stepgen.00.steplen, only the space between the pulses is varied by > the step rate, is that correct? > > I was reading the manual for the new drive I was planning to use in my next > build and see that the drive calls a preference of a 50% duty cycle for step > pulse inputs. I am guessing that it may have something to do with how the > drive's pulse filtering system works, such that for maximum noise filtering > and step reliability having the pulse length be approximately equal to the > step spacing gives the best results. > > So my questions are; Would it be possible to make a Mesa card output a 50% > duty cycle step pattern instead of the current default pattern? And would > doing this even be worth the effort? > Do yopu have a link to that doc? In the drives I've played with using a function generator, a near 50% ratio can help when pushing the drive limits, but generally the speed of the opto-isolator is the ultimate limit, blurring the pulse into almost unrecognizable signals, slowed by the response times of the opto device used. For real dependability at 200 khz and up to the failure of the opto, usually around 375khz, trimming a wee bit one side or the other might get a motor with no load, just laying on the table some good, getting it upto 2000 revs but unless the motor voltage is also cranked uo, torque to do actual work at that speed is just a dream at 45 volts. Some of the nextgen closed loop drivers can use 90-140 volts, overcoming the windings inductance much faster, That makes it possible to make usable torque at 3000 revs. Those higher performance transistors do raise the price a bit. Particularly in the 3 phase versions. But they run like casper the ghost is turning the cranks, Quiet. > Todd Zuercher > P. Graham Dunn > Inc.<https://nam04.safelinks.protection.outlook.com/?url=http%3A%2F%2F > http://www.pgrahamdunn.com/%2Findex.php&data=05%7C01%7Ctoddz%40pgrahamdunn.com > %7C0522ff7789484192c1e808dbd56d7fcc%7C5758544c573f47cebee96c3e0806fb43 > %7C0%7C0%7C638338438551181150%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAw > MDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sda > ta=GD9S6tywNNdc0N2LZQ6I10zMC0BZScL%2FKumvnpWyoz8%3D&reserved=0> > 630 Henry Street > Dalton, Ohio 44618 > Phone: (330)828-2105ext. 2031 > > 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, 1940) If we desire respect for the law, we must first make the law respectable. - Louis D. Brandeis _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
