Hi Aram, I did find a high res encoder at 1250K counts/rev. I'm not really certain that is ppr or in quadrature.
Price is in the $1000 range. http://www.opticalencoder.com/pdf/CP-850-950-HHC.pdf Dave On Apr 22, 2008, at 11:09 AM, [EMAIL PROTECTED] wrote: > Hi > I have 3 questions. > First if to make motor work on very low feed – 0.001 per minute > need only > high resolution encoder than may be needed belt reduction to the > encoder > shaft only, to get more pulses and not to whole motor shaft. Is this > correct? > Second, what is reasonable low feed with direct drive to motors > that have > 8192x4 puls per revolution? > Third, how much those encoder, with 2 250 000 lines, may cost ? > Thanks > Aram > > >> [EMAIL PROTECTED] wrote: >>> Hi >>> I want to build system to tool grinder and that means that my system >>> should behave stable on very low RPM. >>> Minimum PRM 0.0001 per minute. I want to use direct drive with ball >>> screw >>> 5 rev per inch or 1 rev for 5 mm in case of metric system. >>> My motors have 8192 pulse per ….. it takes 4x8192 per revolution. >>> It is >>> AG >>> industrial from servo dynamics. >>> Any fundamentals ideas? >>> Should I use higher resolution encoder? >> If you really need .0001 Rev/Minute, that is 32768 counts * >> .0001 = 3.3 encoder counts/MINUTE, or 18 seconds between each >> encoder count. You can't get smooth motion like that. Of >> course, .0001 RPM x 5 TPI on the screw is a movement rate of >> .00002 IPM. Do you truly need it this slow? >> >> To get smooth motion, you really want an encoder count rate of >> maybe 15 counts/second, or even better, 60. So, for 15 cts/sec >> at .0001 RPM, you need 15 * 60 * 10000 = 9 000 000 counts/rev, >> or 2 250 000 pulses/rev. This will be a pretty expensive >> encoder. (Multiply by 4 for 60 counts/sec.) >> >> Jon >> >> --------------------------------------------------------------------- >> ---- >> This SF.net email is sponsored by the 2008 JavaOne(SM) Conference >> Don't miss this year's exciting event. There's still time to save >> $100. >> Use priority code J8TL2D2. >> http://ad.doubleclick.net/clk;198757673;13503038;p?http:// >> java.sun.com/javaone >> _______________________________________________ >> Emc-users mailing list >> Emc-users@lists.sourceforge.net >> https://lists.sourceforge.net/lists/listinfo/emc-users >> > > > > ---------------------------------------------------------------------- > --- > This SF.net email is sponsored by the 2008 JavaOne(SM) Conference > Don't miss this year's exciting event. There's still time to save > $100. > Use priority code J8TL2D2. > http://ad.doubleclick.net/clk;198757673;13503038;p?http:// > java.sun.com/javaone > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users ------------------------------------------------------------------------- This SF.net email is sponsored by the 2008 JavaOne(SM) Conference Don't miss this year's exciting event. There's still time to save $100. Use priority code J8TL2D2. http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
