On Wednesday 12 February 2020 01:49:34 andrew beck wrote: > the option I just thought of while googling is, can I convert the sin > cos format in to a normal TTL or something like that? even 1000 ppr > would be heaps it is only on the spindle.
One thing you might try, is to use a couple of those $2 rs485 to ttl boards. I bought an encoder to put on the rear of the spindle motor, only to find on its arrival it had a balanced output of only a few millivolts, nothing ttl about it. So I made a small hammond box with two of those in it to translate it to ttl for feeding the encoder in the 5i25. Works a treat. But because the sin/cos is generally magneticly generated, its signal may get weak enough to miss count at very low speeds, which might lead to enough error to make sloppy threads when rigid tapping with a peck routine. It might miscount at the turnaround at the bottom of the hole. > I just want to get the data into the vfd so It knows when the motors > is slowing down. and so I can rigid tap and the existing encoder is a > high quality heidenhian one so might be good to keep it if it is not > too much trouble. ISTR Jon has a board for that, see at PicoSystems.com. > regards > > Andrew > > On Wed, Feb 12, 2020 at 7:43 PM andrew beck <andrewbeck0...@gmail.com> > > wrote: > > Hi guys > > > > wondering if anyone has any ideas here. > > > > I have a heidanhain spindle motor that runs up to 10000 rpm and has > > a 5v sin cos encoder on it. I am currently controlling the motor > > with a schiender vfd. I am talking to the support engineers here in > > New Zealand about buying a encoder card so I can get better low down > > torque. If I run the card in full encoder closed loop control in > > the vfd I can get 200 percent of the torque right down to 0 rpm for > > 30 seconds or so which is pretty useful. I am currently just > > running the drive in Variable frequency control which rapidly looses > > torque at low rpm. > > > > Anyway they have a bunch of cards I can use but don't have a encoder > > card that is suitable for sin cos encoders. I have no trouble > > changing the encoder but am not sure if I can get a source of > > encoders that spin up to 10k rpm. > > > > Anyone have any suggestions? > > > > regards > > > > Andrew > > _______________________________________________ > 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
