On Sun, 25 Dec 2011, gene heskett wrote: > On Sunday, December 25, 2011 04:22:56 PM [email protected] did opine: > >> On Sun, 25 Dec 2011, gene heskett wrote: >>> On Sunday, December 25, 2011 12:08:02 PM [email protected] did opine: >>>> On Sun, 25 Dec 2011, gene heskett wrote: >>>>> On Sunday, December 25, 2011 10:11:27 AM [email protected] did > opine: >>>>>> On Sat, 24 Dec 2011, gene heskett wrote: >>>>>>> On Saturday, December 24, 2011 03:43:00 PM [email protected] did >>>>> >>>>> opine: >>>>>>>> On Sat, 24 Dec 2011, gene heskett wrote: >>>>>>>>> On Saturday, December 24, 2011 02:26:16 PM [email protected] >>>>>>>>> did >>>>>>> >>>>>>> opine: >>>>>>>>>> On Sat, 24 Dec 2011, gene heskett wrote: >>>>>>>>>>> On Saturday, December 24, 2011 01:48:17 PM [email protected] >>>>>>>>>>> did >>>>>>>>> >>>>>>>>> opine: >>>>>>>>>>>> Probotix equipment >>>>>>>>>>>> 40VDC 10Amp Linear Power Supply >>>>>>>>>>>> PBX-RF RF Isolated CNC Breakout Board >>>>>>>>>>>> 3 - Uni-polar Stepper Motor Chopper Drivers >>>>>>>>>>> >>>>>>>>>>> Specs on this driver board please? >>>>>>>>>> >>>>>>>>>> http://www.probotix.com/manuals/ProboStepVX.pdf >>>>>>>>>> >>>>>>>>>>>> 3 - 280 OzIn 8-Wire Stepper Motor >>>>>>>>>>>> >>>>>>>>>>>> I have run this setup for over a year with no problems, so I >>>>>>>>>>>> thought I would create one I have a used Pacific Scientific >>>>>>>>>>>> Powermax II stepper model P21NRXA-LNF-NS-00 I could not send >>>>>>>>>>>> the datasheet for the motor so I sent the link to it >>>>>>>>>>>> http://www.electromate.com/db_support/downloads/Nema23Powerma >>>>>>>>>>>> xI I. pd f >>>>>>>>>>> >>>>>>>>>>> This data sheet shows 2 things, one that it does run hot, very >>>>>>>>>>> hot. 130C in a 40C environment. To me that is too hot, but >>>>>>>>>>> they know their varnish better than I do. Any other comments >>>>>>>>>>> I'll wait for the driver specs to make. >>>>>>>>>>> >>>>>>>>>>>> I >>>>>>>>>>>> added a 4th Uni-polar Stepper Motor Chopper Drivers >>>>>>>>>>>> Wired motor and driver and they actually work >>>>>>>>>>>> >>>>>>>>>>>> Issue 1 >>>>>>>>>>>> The motor gets VERY hot >>>>>>>>>>>> I have run the other motors for a couple of hours and they >>>>>>>>>>>> got hot but the SI motor will burn your fingers after about >>>>>>>>>>>> 15 minutes The manual for the Uni-polar Stepper Motor >>>>>>>>>>>> Chopper Drivers says to set the current limiter to .145 * >>>>>>>>>>>> target_current, 2.8 amps = .406 I reduced it to .38 and it >>>>>>>>>>>> still gets too hot >>>>>>>>>>>> >>>>>>>>>>>> Issue 2 >>>>>>>>>>>> The motor is slow >>>>>>>>>>>> The label says max 1500 rpm but I can only get a fraction of >>>>>>>>>>>> that I use EMC 2.4.6 >>>>>>>>>>>> The driver is set to 1/8 stepping >>>>>>>>>>>> >>>>>>>>>>>> [AXIS_3] >>>>>>>>>>>> TYPE = ANGULAR >>>>>>>>>>>> HOME = 0.0 >>>>>>>>>>>> MAX_VELOCITY = 360 >>>>>>>>>>>> MAX_ACCELERATION = 5000.0 >>>>>>>>>>>> STEPGEN_MAXACCEL = 6250.0 >>>>>>>>>>>> SCALE = 4.44444444444 >>>>>>>>>>>> FERROR = 1 >>>>>>>>>>>> MIN_FERROR = .25 >>>>>>>>>>>> MIN_LIMIT = -9999.0 >>>>>>>>>>>> MAX_LIMIT = 9999.0 >>>>>>>>>>>> HOME_OFFSET = 0.0 >>>>>>>>> >>>>>>>>> Off topic, from this I assume its running a rotary table? >>>>>>>> >>>>>>>> Probably but now it is just a motor sitting on the bench >>>>>>>> >>>>>>>>> If that table has the usual 72 or 90 gear down, those settings >>>>>>>>> are a bit off. >>>>>>>> >>>>>>>> If I do gear this thing down I will fall asleep waiting for it to >>>>>>>> turn >>>>>>>> >>>>>>>>>> From one of my ini files that included a 425oz motor on a 4" >>>>>>>>>> Grizzly >>>>>>>>> >>>>>>>>> table, direct drive to the worm: >>>>>>>>> [AXIS_3] >>>>>>>>> TYPE = ANGULAR >>>>>>>>> HOME = 0.0 >>>>>>>>> MAX_VELOCITY = 81.8965517241 >>>>>>>>> MAX_ACCELERATION = 1200.0 >>>>>>>>> STEPGEN_MAXACCEL = 1500.0 >>>>>>>>> SCALE = 200.0 >>>>>>>>> FERROR = 1 >>>>>>>>> MIN_FERROR = .25 >>>>>>>>> MIN_LIMIT = -9999.0 >>>>>>>>> MAX_LIMIT = 9999.0 >>>>>>>>> HOME_OFFSET = 0.0 >>>>>>>> >>>>>>>> Your setting do get me more rpms but g0 a180 results in many >>>>>>>> revolutions In the not too distant future I hope to be driving a >>>>>>>> rotary table with this So how do I adjust these setting for >>>>>>>> whatever my final reduction will be >>>>>>> >>>>>>> That scale is telling emc how many steps it has to move the motor >>>>>>> to make one units worth of motion. For a table I think its 1 >>>>>>> degree but I can be corrected since it could be a radian too. >>>>>>> What I meant by the geardown, is how many turns of the dial handle >>>>>>> shaft on the table does it take to make one full 360 degree turn, >>>>>>> and depending on the table it could be 90 or 72 full turns of the >>>>>>> worm shaft to make one full turn of the table. >>>>>> >>>>>> I am still quite confused >>>>>> My ignorance is killing me >>>>>> >>>>>> [EMCMOT] >>>>>> EMCMOT = motmod >>>>>> COMM_TIMEOUT = 1.0 >>>>>> COMM_WAIT = 0.010 >>>>>> BASE_PERIOD = 28000 >>>>>> SERVO_PERIOD = 1000000 >>>>>> >>>>>> [TRAJ] >>>>>> AXES = 4 >>>>>> COORDINATES = X Y Z A >>>>>> MAX_ANGULAR_VELOCITY = 8035.71 >>>>>> DEFAULT_ANGULAR_VELOCITY = 60.00 >>>>>> LINEAR_UNITS = inch >>>>>> ANGULAR_UNITS = degree >>>>>> CYCLE_TIME = 0.010 >>>>>> DEFAULT_VELOCITY = 0.33 >>>>>> MAX_LINEAR_VELOCITY = 3.30 >>>>>> >>>>>> [AXIS_3] >>>>>> TYPE = ANGULAR >>>>>> HOME = 0.0 >>>>>> MAX_VELOCITY = 7633.92857143 >>>>> >>>>> Laying on the table & measuring the shaft rotation, this wouldn't be >>>>> very fast. a fraction over 21 rpm, nominally 3 seconds per rev. Not >>>>> rps, rpm. But when 'scaled' to drive a table, its way faster than >>>>> any stepper could be driven to at my usual psu voltage of 28 volts. >>>>> A big Gecko running on 80 volts, maybe. >>>> >>>> MAX_VELOCITY = 7633.92857143 (degrees per second), right????? >>>> (7633.92857143 / 360) * 60 = 1272.32142857166666666660 rpm >>>> Which is what I see whem I test with stepconf >>>> But locks up in Axis >>> >>> Locks up the computer, or the motor? >> >> "Locks up" bad me >> I meant I get "joint 3 following error" and Axis power button shuts off >> I have to press F2 to continue >> >> After long boring changing ini and restart Axis I get >> >> MAX_VELOCITY = 1925 >> MAX_ACCELERATION = 15000 >> STEPGEN_MAXACCEL = 18000 > > at risk of being boring, reducing these by a /20 would maybe let you > increase MAX_VELOCITY a bit more. At 1200 & 1500 in my settings, I can > actually hear the motors coming up to speed over about 1/4 of a motor rev, > and slow at the same rate when stopping. > > OTOH, and this is unk to me, you could be pretty close if these values are > also stated in end effector units per minute. Perhaps someone familiar > with the emc innards could clarify that? > > If that is the case then I've been barking just to make me look silly. > Taint the first, likely won't be the last. :) > >> SCALE = 4.44444444444 >> >> These are the maximum values that work >> Any higher and I get "joint 3 following error" >> >> At these setting 'g0 a..' show 115500 in Axis Vel indicator >> I assume this is degrees/minute ~ 320 rpm > > And that sounds rather like I would expect but I don't know what your motor > supply voltage is. I don't think my 28 volt supply can quite make that. > >> Also 'g0 a180' causes the motor to turn 180 degrees so all I have to do >> is multiple SCALE time whatever my final reduction turns out to be > > Correct, as far as it goes, I believe the MAX_VELOCITY will also need > scaled in the opposite direction by the same amount because (IIRC) this is > also stated in "end effector" units per minute. > > IIRC I started with an undamped 252 oz/in motor, so that configs limits are > set at 81 degrees/min, which since I swapped motors, built a new driver > setup, and installed the damper can probably be raised considerably. > >> I would still be interested if someone could explain, in simple terms >> for me, why stepconf settings do not work > > I did the config I've been referencing by ear so to speak as stepconfig > wasn't yet available when I built this el-cheapo motorized table for mine. > Its been a while, with the 'while' measured in years. I need to change the > .hal file for the new parport card, and see if it still works, its been a > good 2 years since it was last mounted on my mill. >
Thanks for the pointers, I think you have dumbed it down as much as possible Being thick and persistant is not a good combination It works anyway Richard ------------------------------------------------------------------------------ Write once. Port to many. Get the SDK and tools to simplify cross-platform app development. Create new or port existing apps to sell to consumers worldwide. Explore the Intel AppUpSM program developer opportunity. appdeveloper.intel.com/join http://p.sf.net/sfu/intel-appdev _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
