Actually, there are a lot of servo's like this (w/ step and direction). But, cost comparison is the issue.
Omron and Panasonic servo's only accept step and direction (the ones I looked at) and you can probably get them off ebay for a decent price. I had once used Omron and was actually complaining they didn't have a +-10Vdc interface and only took step and direction. I think one reason is the Omron's are designed to be used w/ a step and direction output from their PLC's, that historically didn't do analog servo control, at least from the brick versions. I always wondered why they just didn't add the analog to the servo drive, but oh well. Also, here's a brand that BeachBumPete (from the IRC) used on his Cincinnati mill retro that accepts step and direction: http://www.dmm-tech.com/ I haven't used them, no affiliation w/ any of these, but the dmm guys also have a lower cost servo i just saw, DYN2 AC Servo Drive is step and direction and analog input... Chinese servo's from Alibaba or a place like salescnc.com have step and direction servos: http://salecnc.com/catalog/Delta-Taiwan-Servo-MotorDrive-Set-400W-3000RPM?osCsid=du1blviq6dlbi02nscik0akre1 While that $350 price is high for a stepper solution, it's waaaayyy cheap for a servo drive and servo motor combo (with cables). For Kollmorgen servo's you're looking at a couple hundred bucks just for the cables!!! I think the bottom line is that the servo pricing hasn't come down like the bare-bones stepper motor and $50 stepper driver pricing. If you are cost conscious, steppers are the easier route. In Gene's case, to match the cost competitiveness, he would need to shop ebay for the 'right' deal and those don't come by everyday. Good Luck, Mark On Tue, Jan 24, 2017 at 11:17 AM, Andrew <pkm...@gmail.com> wrote: > 2017-01-24 19:37 GMT+02:00 sam sokolik <sa...@empirescreen.com>: > > > PWM/dir though the bob. (these amc drives instead of +/-10v take > pwm/dir) > > > > Ah, so convenient. We could save a lot on 7i77's if all servo drives were > like this ) > > Andrew > ------------------------------------------------------------ > ------------------ > 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 > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > ------------------------------------------------------------------------------ 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 Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
