On Tuesday 20 October 2009, Thomas Kaiser wrote: >On 10/20/2009 08:05 PM, Kirk Wallace wrote: >> On Mon, 2009-10-19 at 20:25 +0200, Thomas Kaiser wrote: >>> Hey >>> >>> Does anybody on this list use the "UHU Servocontroller" >>> [http://www.uhu-servo.de/]? >>> If so, what are the experience with this? What motors you are using? >>> >>> I am just interested at anything somebody did with this ;-). >>> >>> Thomas >> >> In my opinion, step/direction servo motor controllers are not ideal for >> EMC2, since the motion control (PID) and position feedback is built in >> to EMC2. For servo's, a PWM or analog input driver is better. With this >> kind of driver, you will have access "under the hood", allowing you to >> tune and customize your system through EMC2's HAL. Many step/dir >> controllers only have a separate Windows program for tuning. >> >> UHU is a do-it-your self project, so if you want to build something >> yourself this may help: >> http://www.electronicsam.com/images/KandT/servostart/schem/ >> >> Or you can copy a reference h-bridge design from one of the chip >> manufacturer's data sheets. When you get into the higher power motors, >> you will need to allow for current limit control, FET shoot-through, and >> fly-back currents. Usually, it is better to purchase higher power >> drivers. > >Hello Kirk > >I try to give new life to an old Schaublin lathe. On this lathe the NC >controller died. Everything else seems to be OK. So, I am trying to >replace the old NC controller with EMC, which worked so far for the X-Z >axis :-) > >The old NC controller just sent pulse and direction signals to the >drives. But as far as i can tell, the motors are DC motors with encoders >and look more like servos. These drives are still working and I hooked >up EMC in stepper configuration (parallel port) which works :-) > >My goal is to just replace the NC controller and use as lot as possible >things which are still working. > >I just was thinking what would happen when one of the drives dies (no >spare parts available anymore).
A _good_ tech (ask to see his CET certificate, I have one) can find the bad parts, and in all likelyhood, replace them with newer, stronger devices should that untidy thing happen. The VSD for my x1 mill has already been fixed, by me, using hexfets lifted from a dead for other reasons computer PSU. With the new (used) hexfet, I could probably double the size of the fuse in it as it runs obviously cooler now than when new. So unless you cannot find such a person within a suitable distance, that failure shouldn't be given that high a priority in your worries. >It would be handy to replace the dead >drive with something similar, keep the old motor and the "old" stepper >(parport) configuration. I think UHU Servocontroller would be a good >alternative. > >Here is a link from the same machine I am working on. But they replace >everything with a new Siemens control. I will stay with EMC! > >http://www.wfrauenfelder.ch/LAP2005/LAP2005.htm > >The 2 first pictures are with the old controller and drives. > >Thomas > >PS: I am an electronic engineer, so no problem with DIY projects ;-) I am not, papered at least, just 60 years experience doing similar work, but getting my hands a lot dirtier doing it. I got my CET cert in 1972, Piece of cake. :-) I tried to order a DPST power switch for my 6" jointer today so I could put it on a 240 circuit I ran Saturday. And found they want another $30 US for the switch just because they added 3 more pieces of brass for contacts to the existing precast switch housing. Since its a $3 switch in SPST, I almost fell off my chair laughing at them. Humm, I wonder if I can make one out of two?, since the one I ordered also came as SPST after they assured me it was for the 230 volt version, and SPST is totally sick bird on a 240 volt circuit. And they live, even breed among us... :( -- Cheers, Gene "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) The NRA is offering FREE Associate memberships to anyone who wants them. <https://www.nrahq.org/nrabonus/accept-membership.asp> The words fly away, the writings remain. ------------------------------------------------------------------------------ Come build with us! The BlackBerry(R) Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9 - 12, 2009. Register now! http://p.sf.net/sfu/devconference _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
