On Thursday 15 October 2020 12:55:16 Chris Albertson wrote: > Gene just Google the part number "VNH3SP30". Polulu has them. It is > in fact my "go to" driver. These were developed for automotive use > for things like driver seat adjustment motors. > > Polulu's version of this has reverse voltage protection but they > seriously de-rate the chip. Just read the datasheet that is linked > from their site. > I have the STM docs printout on that chip under my left elbow. 2 things I note from that.
1. direction changes are slow. No consequences when driven by the human hand running a joystick on the side of the seat, but important for computer control. 2. No evidence from the waveforms shown that the pwm is used for anything but a logic clock. At no point in the waveforms shown starting on page 13, is there any evidence of the pwm actually modulating the outA or outB voltage in time with the input pwm. This is designed as an on/off control only, and low standby current consumption in the very low microamps was the prime specification driver. The boards I have ordered, unless they are doing something that STM does not know or show, are not capable of pwm driven analog control. So while I may hook it up, I can't see it as working as a servo because its un-modulated by the pwm input. Which is why I also have a pair of 150 watt rated class-D audio amps ordered. For a similar price. They are rated only for 27 volts. Higher voltage and wattages priced accordingly. I'll turn that 24 volts down as low as it can go, and smoke test it. I also have some A-D 48 volters that will turn down to 42.5 that might be usable with the 400 watt versions. Over current foldbacks on those not tested, but they sure run a 3 phase, 2 or 3NM rated stepper very nicely on the Sheldon lathe. Both sweet and silent compared to regular steppers. > Here is the way I used these... > I buy a slightly different version of the chip that comes on an > "Arduio Sheild" ebay link > <https://www.ebay.com/i/401089386943?chn=ps&norover=1&mkevt=1&mkrid=71 >1-117182-37290-0&mkcid=2&itemid=401089386943&targetid=934793863816&devi >ce=c&mktype=pla&googleloc=9031026&poi=&campaignid=10877149888&mkgroupid >=107912403075&rlsatarget=aud-622524042918:pla-934793863816&abcId=930040 >0&merchantid=101638797&gclid=CjwKCAjw5p_8BRBUEiwAPpJO6-QTPa9wyIxLjU-wVv >6qq8PaY8DUPaxrZw7TRhXg8XKzfNEiapIrIhoCidAQAvD_BwE> Then I buy a Nucleo > board from STM www.digikey.com/...NUCLEO-F401RE > <https://www.digikey.com/en/products/detail/stmicroelectronics/NUCLEO- >F401RE/4695525?WT.mc_id=frommaker.io> These mate together with a bunch > of 0.1" header pins. > > With some software in the STM32 I now have a USB connected dual motor > driver that can handle up to about 20 amps peak and 12 A continuously > The control PID loops run on the STM32 and I only have to send speed > or position commands over the USB cable. It would be about as easy to > assemble an Ethernet or SPI connected motor controller from these same > parts. The stack-up is a little bulky but it is so easy to do and > cheap I can put up with the excess cubic volume. > > On Thu, Oct 15, 2020 at 9:12 AM Gene Heskett <ghesk...@shentel.net> wrote: > > On Thursday 15 October 2020 08:32:07 Roland Jollivet wrote: > > > Maybe this is good for you, if available locally; > > > > > > https://www.olimex.com/Products/Robot-CNC-Parts/MotorDrivers/BB-VN > > >H3SP 30/open-source-hardware > > > > I give up, none of the 3 USA distributors are carrying that item. > > > > > On Wed, 14 Oct 2020 at 22:42, Gene Heskett <ghesk...@shentel.net> > > > > wrote: > > > > After it finally was delivered, testing looks good but now I > > > > need a controller, smaller and lower voltage than one of Jons > > > > pwm-servo's. > > > > > > > > This motor supposedly turns 220 rpms no load with 24 volts > > > > applied. > > > > > > > > It has an encoder on the rear which is making a 5.4khz > > > > quadrature signal when its running free, out of 4 wires, no > > > > index which is fine as I'll put a switch on the BS-1 for a > > > > home/index anyway. > > > > > > > > This motor draws 4 amps at max rated 100 watt input. > > > > No clue what the LRA amps is but it does jump pretty good > > > > getting started so I'd expect startup in-rush to be at least 10 > > > > amps. > > > > > > > > I'd like to control its position like a common rotary servo > > > > axis, so what do we have in our linuxcnc toolbox that looks like > > > > a bi-dir pwn controlled twin H bridge to run a 24volt brushed > > > > PMDC motor with a 10 amp in-rush as if it were a servo? > > > > > > > > Thanks all. > > > > > > > > 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) > > > > If we desire respect for the law, we must first make the law > > > > respectable. - Louis D. Brandeis > > > > Genes Web page <http://geneslinuxbox.net:6309/gene> > > > > > > > > > > > > _______________________________________________ > > > > 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 > > > > 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) > > If we desire respect for the law, we must first make the law > > respectable. - Louis D. Brandeis > > Genes Web page <http://geneslinuxbox.net:6309/gene> > > > > > > _______________________________________________ > > Emc-users mailing list > > Emc-users@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/emc-users 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) If we desire respect for the law, we must first make the law respectable. - Louis D. Brandeis Genes Web page <http://geneslinuxbox.net:6309/gene> _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
