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/Nema23PowermaxII.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.

So the motor, direct driving the worm shaft, will have to make that many 
full turns time the motors steps to make a full (1 degree, 1 radian, or 360 
degrees depending on your agreed on unit of measurement size) turn times 
the microstep in use in the driver.

For my case, I'll have to re-adjust that scale in my .ini file because I 
recently fried the xylotex driver board, and replaced the whole kit & 
kaboodle with a quad of MM-542 drivers running at 16x, but still running at 
28 volts.  I haven't had the table on the mill recently because I am trying 
to modify it for an air driven automatic brake so I don't have to fight 
with its backlash in real time.  What can I say, its a $99 table.  ;-)  And 
rather than run the big compressor & fool with all those solenoid air 
valves, I have considered a power supply from junkbox parts, and a 12 volt 
tire inflator just switched on when I need to release the brake by 
pressuring the inside of the table.  West Virginia shade tree engineering 
at its finest, only one relay to turn on the compressors psu. :)

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)
My web page: <http://coyoteden.dyndns-free.com:85/gene>
knowledge, n.:
        Things you believe.

------------------------------------------------------------------------------
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

Reply via email to