On Saturday 11 August 2018 23:40:37 Jon Elson wrote: > On 08/11/2018 08:03 PM, Gene Heskett wrote: > > On Saturday 11 August 2018 20:14:46 Jon Elson wrote: > >> On 08/11/2018 03:37 PM, Gene Heskett wrote: > >>> On Saturday 11 August 2018 15:29:43 andy pugh wrote: > >>>> On 11 August 2018 at 20:11, Gene Heskett > >>>> > >>>> <[email protected]> wrote: > >>>>> Where can I find a tut on how the resolver works? > >>>> > >>>> https://en.wikipedia.org/wiki/Resolver_(electrical) > >>> > >>> Quite simplified, covers the basics but makes little or no > >>> mention of the > >>> resolvers speed limits. So in both cases, the encoder is > >>> king, and much > >>> cheaper to implement. > >>> > >>> Thanks Andy. > >> > >> Analog Devices 2S1200 will track a two-pole resolver to > >> 60,000 RPM (1000 RPS). > >> > >> Jon > > > > And the heat sink and fans are how big? > > The 2S1200 chip is CMOS, and runs completely cold. Don't > know about the 60K RPM motor. > We have a thing that spins a sample in an MRI magnet field > at work at 300K RPM (5000 RPS). > it is a tiny ceramic thing with notches in it, it forms an > air bearing and an air jet shoots at the notches to spin in > like a turbine. CRAZY technology.
Air bearings are nice. Run forever with no wear, if the air is truly clean. > Jon Dentists have been doing that at 150k revs for what, 30 years? :) -- 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 [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
