On Wed, Apr 11, 2018, at 10:30 AM, David Berndt wrote: > I'd like this to be reasonably low effort. My biggest concern is single > phase input. Control/response requirements are about as low as it gets. > > I'm looking to output about 1000lbf in a linear direction via a > crank/slider or ballscrew with peak speed of about 1m/s. So that's a real > 5hp of energy.
Mixed units are making my head hurt.... 1000lbf = 4448 newtons I think? At 1m/s, that is 4448 watts. 1 HP = 746 watts, so 4454 watts = 5.96HP. A ballscrew would have to spin pretty fast to hit 1m/s. Obviously it depends on the pitch, but a plain vanilla 5mm pitch screw would have to go 12000 RPM (well above critical speed unless very short). Even a 20mm pitch screw would need 3000 RPM. You don't mention the stroke length. Are you moving a few inches in a fraction of a second, or several meters over several seconds? 4.5kW or 6HP isn't going to be small or cheap no matter what you do... > Duty cycle will be low, and external active cooling can be > provided if required. So things like steppers are out, I've never seen a > stepper that outputs nearly that much, and I don't particular want to > create a 4kw 80v dc power supply... > > re: Control requirements, I really only need to start running at a > particular speed and be able to return the system to a somewhat close stop > position, which can be as simple/bad as a vfd with a switch and timed jog. > Any extra control over the system that I can get would add capabilities > though. > > The goal here is to see if there are any industrial drives out there that > might periodically pop up on ebay which are higher KW and single phase > capable.I see units like the Parker Gemini GV/GV6-U12/H20 which claim > single phase at 3.5kw and 5.9kw. > > Dave > > > On Wed, 11 Apr 2018 09:24:32 -0400, Dave Cole <linuxcncro...@gmail.com> > wrote: > > > How much time/work do you want to put into this motor/drive setup? > > There are no really cheap large servo motor solutions unless you stumble > > into a deal on Ebay or a surplus marketplace. > > Larger servos generally mean 3 phase inputs. So that becomes an > > immediate issue. > > > > If you can live with a VFD, your life will be much simpler to simply get > > a single phase input VFD and a suitable motor. > > You can find 3 phase gearbox equipped motors on Ebay that can get you > > 500 rpm max. > > > > Dave > > > > > > > > On 4/11/2018 2:01 AM, David Berndt wrote: > >> Wondering if anyone had any preference/experience/advise to share with > >> single phase capable larger servos. I'm looking at an application for a > >> 3 to 5hp motor with a vfd, but if I could just get a servo to fill in > >> that'd be nice. Gear reduction will be required, but something with > >> more torque, needing less reduction will make things easier.Say ~500rpm > >> as a goal maximum output. > >> > >> I see things like Fanuc red cap servos (ai series? pulsecoder encoder) > >> 2.5kw kicking around ebay. Driving something like that would seem to be > >> the challenge? > >> > >> Thoughts? Suggestions? Previous experience? > >> > >> Dave > >> > >> ------------------------------------------------------------------------------ > >> > >> 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 > > > > ------------------------------------------------------------------------------ > > 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 > > ------------------------------------------------------------------------------ > 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 -- John Kasunich jmkasun...@fastmail.fm ------------------------------------------------------------------------------ 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
