On 3/10/2015 10:39 AM, jrmitchellj . wrote: > A couple more neatness thoughts. > I would keep signal wires down close to the metal plate everything is > mounted on. Will do.
> Also, it looks like you motherboard is up on standoffs. I would keep > that down close to (1/4 to 5/16") the metal plate. The 2.5" hard drive is under the motherboard. Currently wrapped in bubble wrap, but I've been considering replacing it with a bootable USB flash drive or something else smaller. > Keep all signal wires way from the transformer!!! Yes. > And the last thing that I did not see mentioned elsewhere, do you have > the step & direction timing parameters set up correctly for the > stepper drive. My first system, I used drives that needed very > particular timing & polarity. I had the timing correct, but polarity > flipped. It made for very erratic & unpredictable stepper operation. I was tinkering with this yesterday... currently the step signals idle high ( so the optos on the IM483s are off), and pulse low. But I do need to research the timing requirements of the IM483s. > In many of my builds, I use sacrificed CAT5 cables that I strip off > the sheath and use the twisted pairs for internal signal wiring. The > twists are very uniform for the very reason of keeping adjacent > signals out. I do have to rewire and clean up properly. I have some slotted wire duct ( http://www.mcmaster.com/#7578K41 ) but space is too tight in some areas to even mount this. I have a bit of room to slide the mobo over so I can mount the duct between the mobo and IM483s. Thanks, -Neil > > Good luck. > > Ray > > --J. Ray Mitchell Jr. > jrmitche...@gmail.com <mailto:jrmitche...@gmail.com> > (818)324-7573 > > > The things we admire in men, kindness and generosity, openness, > honesty, understanding and feeling are the concomitants of failure in > our system. And those traits we detest, sharpness, greed, > acquisitiveness, meanness, egotism and self-interest are the traits of > success. And while men admire the quality of the first they love the > produce of the second. > -John Steinbeck, novelist, Nobel laureate (1902-1968) > > > On Mon, Mar 9, 2015 at 7:50 PM, Neil <emc_d...@narwani.org > <mailto:emc_d...@narwani.org>> wrote: > > Adding one more note -- I've been testing/verifying with a dial > indicator mounted to the machine, so I know I had a major issue before > and I know it's resolved now. > > Cheers, > -Neil. > > > On 3/9/2015 9:54 PM, Neil wrote: > > Bingo! I found the issue! > > > > So follow along with me here. In this pic, the yellow arrow on the > > right points to my 12V-to-5V buck converter, for the opto supply. > > Purple wire out of it is 5V to the IM483s. The black ground > wire out > > of it was connected (follow the yellow dots) to the ground of the > > motor power supply (34V) !!! It has been at least a few years since > > this was put together, so I'm not sure why. > > > http://orlandorobotbuilders.com/rw/2015-03-08-Elec-04-GroundIssue.jpg > > > > With this wire, I had 1.8Vp-p noise on the 3.3V (actually 3.1V > > measured) step/dir lines. > > Once I removed this, I got 3.1V ~300mVp-p noise. > > I put back my optoisolator board and got 4.2V +/- 300mVp-p noise. > > Then I switched to shielded wire (USB wire) and still got > 300mVp-p noise. > > I changed to using the 5.0V from the USB header on the mobo and > still > > got 300mV. I'll keep that, but will need to put my 12V-5V > switching > > converter as I need the power for other things that will be on > the board. > > > > When I get time again, I'm going to try tighter twisted pair. > > > > Thanks for all the help! > > > > Cheers, > > -Neil. > > > > > > On 3/8/2015 11:25 PM, Dave Cole wrote: > >> Andy is right. Bag the 5V power supply and do a port steal > from the > >> USB port for a 5V supply. > >> > >> You can get nice tight twisted wire pairs from a Cat 5 patch cable. > >> > >> Dave > >> > >> On 3/8/2015 6:58 PM, Neil wrote: > >>> Oops... I should've sent this to the list. Also, I'll add that > that > >>> black ground wire test did not make a difference. > >>> > >>> Cheers, > >>> -Neil. > >>> > >>> > >>> On 3/8/2015 7:53 PM, Neil wrote: > >>>> Ah yes... let me clarify that part. If you look at the far > right in > >>>> the pic, just below the plug going into the PC power supply is my > >>>> 12V-5V buck switching PS that provides the opto supply. It's > wrapped > >>>> in heatshrink tubing, but you can see purple & black wires > coming out > >>>> of it. It takes 12V from the PC PS, and puts out 5V on the > purple > >>>> wires. You can see the purple wires going into the IM483s > (on the > >>>> right side). FWIW, the right side of the IM483s in my pic is the > >>>> input side, the left is the motor side, with the orange/black > wire > >>>> pairs being the motor power. > >>>> > >>>> In the quick reference here ( > >>>> > > http://motion.schneider-electric.com/downloads/quickreference/QR_IM483_805.pdf > >>>> > >>>> ), the bottom left of the second page shows the opto wiring. My > >>>> ground reference is essentially it's referenced back to the PC PS > >>>> ground. > >>>> > >>>> As I was experimenting with this, I added that black wire > from the > >>>> DB25 ground on the parport to see if a better ground would > help -- the > >>>> wire goes up, but then comes back down on the right in the > pic (you'll > >>>> see it blocking the PC PS fan) and into the 2 pin white amp > connector > >>>> just above the right-most IM483. You'll see it as a crimped > pin w/o a > >>>> housing. Those 2-pin white connectors are just a bunch of > connectors > >>>> I had wired up to supply 12V around the board as needed. It's 12V > >>>> from the PC PS. > >>>> > >>>> I'll check my 5V with a scope and also try using the 5V USB > power. But > >>>> I suspect shielding will help it a lot. > >>>> > >>>> Cheers, > >>>> -Neil. > >>>> > >>>> > >>>> > >>>> On 3/8/2015 7:23 PM, andy pugh wrote: > >>>>> It isn't clear from that what the signals are referenced to. You > >>>>> appear to only have a single wire from the parport GND to > somewhere > >>>>> out-of-shot. Rather than use a separate supply for the opto > 5V you > >>>>> could steal 5V from a USB port. (Or from a convenient header > on the > >>>>> motherboard) If you take 5V to Opto+ and wire the Opto- to the > >>>>> parport, then invert the sense of the signals in the config > then I > >>>>> suspect you might have better results. > >>>> > >>> > > ------------------------------------------------------------------------------ > >>> > >>> Dive into the World of Parallel Programming The Go Parallel > Website, > >>> sponsored > >>> by Intel and developed in partnership with Slashdot Media, is your > >>> hub for all > >>> things parallel software development, from weekly thought > leadership > >>> blogs to > >>> news, videos, case studies, tutorials and more. Take a look > and join > >>> the > >>> conversation now. http://goparallel.sourceforge.net/ > >>> _______________________________________________ > >>> Emc-users mailing list > >>> Emc-users@lists.sourceforge.net > <mailto:Emc-users@lists.sourceforge.net> > >>> https://lists.sourceforge.net/lists/listinfo/emc-users > >> --- > >> This email has been checked for viruses by Avast antivirus > software. > >> http://www.avast.com > >> > >> > >> > > ------------------------------------------------------------------------------ > >> > >> Dive into the World of Parallel Programming The Go Parallel > Website, > >> sponsored > >> by Intel and developed in partnership with Slashdot Media, is your > >> hub for all > >> things parallel software development, from weekly thought > leadership > >> blogs to > >> news, videos, case studies, tutorials and more. Take a look and > join the > >> conversation now. http://goparallel.sourceforge.net/ > >> _______________________________________________ > >> Emc-users mailing list > >> Emc-users@lists.sourceforge.net > <mailto:Emc-users@lists.sourceforge.net> > >> https://lists.sourceforge.net/lists/listinfo/emc-users > >> > >> > > > > > > > > > > ------------------------------------------------------------------------------ > Dive into the World of Parallel Programming The Go Parallel > Website, sponsored > by Intel and developed in partnership with Slashdot Media, is your > hub for all > things parallel software development, from weekly thought > leadership blogs to > news, videos, case studies, tutorials and more. Take a look and > join the > conversation now. http://goparallel.sourceforge.net/ > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > <mailto:Emc-users@lists.sourceforge.net> > https://lists.sourceforge.net/lists/listinfo/emc-users > > ------------------------------------------------------------------------------ Dive into the World of Parallel Programming The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net/ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
