On Saturday 24 August 2019 13:31:44 Gene Heskett wrote: > On Saturday 24 August 2019 12:46:28 John Dammeyer wrote: > > > > I already have my mill running with a single parallel port but > > > > the single phase motor is still controlled with a switch because > > > > I'm too lazy to temporarily wire in a relay. What I do have for > > > > my mill is a sweet Bergerda 1.8kW AC Servo that works very > > > > nicely with step/dir signals and has a 2500 line encoder (10,000 > > > > pulses per rev) which means it needs more than the parallel port > > > > can deliver. > > > > > > Yes, that encoder will run out of bandwidth trying to get thru > > > that bobs opto-iso circuitry. So you are out the cost of at least > > > a 5i25 which has at least 100x more bandwidth at its encoder > > > inputs. I've had to cut and bypass the opto crap on the bobs > > > several times now. I am a CET, but many machinists far more > > > capable than I at turning cranks, wouldn't feel comfortable doing > > > such hacking. > > > > Actually not a problem. Especially for the spindle. > > Thats 10k edges per rev, and 3000 revs, that 300,000 edges a second, > and right at or slightly beyond the bandwidth you can shove thru an > opto-isolater. Expect problems John. > > Here on the g0704, I have a 1000 line encoder on the rear of that 1hp > 90 volt motor. At 1500 spindle revs, the multiplier is just above > 14000/rev, so the input to the encoder is coming in at 21,750,000. Its > been run thru a couple rs-485 convertors, but the 5i25 is not haveing > problems with it. Which amazes the heck out of me. But mama says shes > hungry, and see that famous sign. Back eventually. > > > The drive also > > has a numerator/denominator step multiplier on the input. I tested > > this by replacing a smaller DC brushed servo that has a 250 line US > > Digital encoder (x4=1000 per rev) and set the numerator to 10. It > > was plug and play at that point. Nothing changed with the hal or > > ini file. Just a smaller AC servo running the X axis. Sweet > > > > And I can also program in a numerator/denominator pair on the > > encoder outputs. So I can make the motor encoder appear like one > > that has 200 pulses per rev. Aside from the poor manual I'm really > > liking the Bergerda AC Servos. I may be ordering some more in the > > near future.
Found the site, chinky of course, Model #? > > > > So that means > > > > a Smooth Stepper and MACH3 or the MESA 7i92H which is the > > > > cheaper option and plugs directly into my existing BoB. (part > > > > of the criteria). > > > > > > I'll have to look at the 7i92. Just did, wouldn't consider it as > > > it would tie up the single net port on most motherboards. I > > > consider a working network a requirement and all my machines can > > > browse the net. > > > > It's pretty inexpensive to order a second Ethernet Board. I have > > one but the bracket is for full height mounting. I need a short one > > for this PC. > > > > > Take care John. And I'm sure I'll learn something from it. > > > > I'm definitely learning a lot from trying all these different motor > > drivers. The one I haven't tried yet is the Gecko DC Servo drive. > > I have two of those that will probably just be sold. Now that I've > > played with the physically smaller drives that only need 220VAC > > input and not a separate power supply I can't see using the Gecko. > > My DC Brushed motors are 90VDC. > > I'm using 2 of Jon's (pico systems) pwmservo drives against 90 volt > motors, with supplies in the 127 volt range, and limited to 17 amps or > so. So the 1hp is probably twisting close to 2 hp. They seem to love > it. > > > The Gecko can't go that high. The next > > power supply I have is 60V for the knee stepper motor. I'm now > > thinking about how I'll change to the AC Servo for that. Haven't > > bothered with the quill. It's locked fully up for now. > > Neither have I. Just a medium sized 950 oz nema 34 on the mills head sled. The 1600 oz I took off as too slow, is working fast enough on the sheldon but noisy, rattles the keyboard shelf I bolted to the top of its mount bad enough I had to put a 1/4 round, 1/4" high mouse retainer fence around the edge. The mouse has a tendency to spit out batteries and such as it bounces off the concrete floor. ;) I should reduce its current, in favor of a less violent microstep. Or put a smaller motor I don't have on it. Now if I just felt froggy enough to go change that psu in the g0704's 'puter. But not today as that would put me 3 steps up a stepladder. That would probably give the docs bad dreams, so that may wait till the new valve is installed. > > Thanks for the feedback Gene. > > John > > > > > > > > > > _______________________________________________ > > Emc-users mailing list > > Emc-users@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/emc-users > > Cheers, Gene Heskett 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
