On 1/26/2016 11:47 AM, andy pugh wrote: > On 26 January 2016 at 07:00, Dave Cole <linuxcncro...@gmail.com> wrote: >> If Siemens can't get standard AC squirrel cage motors to position >> precisely, I doubt that anyone can. > They can't with standard induction motors. But induction servo motors > do exist and Siemens make them: > https://support.industry.siemens.com/tf/ww/en/posts/asynchronous-servo-motor-v-s-asynchronous-motor/75942/?page=0&pageSize=10
The term "servo motor" does not necessarily imply a positioning drive. This is Siemens explanation since they make so many drives and motors for different uses: https://mall.industry.siemens.com/mall/en/WW/Catalog/Products/10045149?tree=CatalogTree Notice that the 1PH8 motors are Simotics M main motors and they say they are for precise and smooth running of rotary axes. The Simotics S is the true positioning servo motors that are put on CNC machines for position drives. Years ago (early 90's) when I was working for Siemens, I visited a company in or near Cleveland, OH that was making high end spindle drives and motors. I forget the company's name. But the company contacted Siemens since they wanted to use Siemens drives with their motors. I think I was one of the first guys to visit the company from Siemens. At the time, the existing Siemens drives could not control their motors. Their motors were a hybrid motor that could be act as an induction motor at high speeds yet could do very accurate positioning at low speeds with decent torque. It was a near perfect motor for a machine tool spindle. About a year later Siemens bought the company and acquired their patents and dissolved the company. I met the company owner and I think he was happy to sell out to Siemens. I'm sure that he did very well in the sale. Dave ------------------------------------------------------------------------------ Site24x7 APM Insight: Get Deep Visibility into Application Performance APM + Mobile APM + RUM: Monitor 3 App instances at just $35/Month Monitor end-to-end web transactions and take corrective actions now Troubleshoot faster and improve end-user experience. Signup Now! http://pubads.g.doubleclick.net/gampad/clk?id=267308311&iu=/4140 _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
