On Thursday 14 July 2016 11:20:03 dave wrote: > On 07/13/2016 03:49 PM, Gene Heskett wrote: > > On Wednesday 13 July 2016 15:57:38 Leonardo Marsaglia wrote: > >> Hello Jon. > >> > >> Well, the encoders that are already installed on one of our > >> machines are labelled with the Index pulse. The thing is I can't > >> read the pulse with halscope for example. > > > > I don't think halscope is going to catch it unless you have it > > running in free roll and are turning the motor/encoder slowly by > > hand. You can either watch it with a good 200 Mhz digital scope, or > > some breakout boards have led tally's that I have found to be > > handier than sliced bread or bottled beer, you just turn the motor > > very slowly while watching the leds. > > > >> I just tried to use the home using only index pulse and apparently > >> the index pulse is working because the axis latches until it stops > >> and it turns always a single turn more or less eyeballing it. > >> > >> The strange thing is I that I can't trigger the scope with the > >> index pulse on LinuxCNC, and also I can't measure the index on my > >> other encoders. I guess I should try to wire them to a LinuxCNC pc > >> and make home manually to see if they work ok. > >> > >> 2016-07-13 14:29 GMT-03:00 Jon Elson <[email protected]>: > >>> On 07/13/2016 08:56 AM, Leonardo Marsaglia wrote: > >>>> Hello to all. > >>>> > >>>> We just tested some Heindenhain encoders and as happened with > >>>> other encoders we can't sense the index pulse. We tried to detect > >>>> it with a 20 nano seconds period on a digital scope but nothing > >>>> happens. All the other pulses are working perfect except the > >>>> index one. > >>>> > >>>> I have to mention that this happened with other encoders too, but > >>>> since > >>> > >>> we > >>> > >>>> didn't need to use them with index pulse on the other machines we > >>>> just > >>> > >>> let > >>> > >>>> it that way and didn't worry about it. > >>> > >>> Well, if the scope does not trigger on it, and it triggers > >>> fine on the A and B, then it just isn't there! > >>> Now, of course, the index will only happen once per rev, so > >>> you have to make a full turn to see the pulse. > >>> Are you SURE these encoders actually have the index pulse? > >>> > >>> Jon > > In desperation and lacking a scope I would try logic. Set a FF and use > it to drive an LED. > Should work rather nicely for slow speeds like hand turning the > encoder. I'm sure the logic guru's will have even better suggestions > but this should do the job. > > Dave > Absolutely Dave.
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) Genes Web page <http://geneslinuxbox.net:6309/gene> ------------------------------------------------------------------------------ What NetFlow Analyzer can do for you? Monitors network bandwidth and traffic patterns at an interface-level. Reveals which users, apps, and protocols are consuming the most bandwidth. Provides multi-vendor support for NetFlow, J-Flow, sFlow and other flows. Make informed decisions using capacity planning reports.http://sdm.link/zohodev2dev _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
