Using the opto ioslators as voltage translators should work. Note the data sheet has the words "not recommended for new design" on it. There is likely a newer part. But maybe you have these on hand already?
These isolators will do 10 Mbits/second, likely fast enough. The bottleneck is the RC filter made using the 1K resistor and 0.1 uF cap (time constant of 0.0001 second) One other idea. Can you run the encoder from a 5 volt power supply? Then there is no need for level conversion At 1,000 RPM and 500 pulses per revolution you get 8333 pulses per second. Your low pass filter might be a little too aggressive. But I don't know the max shaft RPM. But do check this. On Sat, Oct 9, 2021 at 12:39 PM Gene Heskett <ghesk...@shentel.net> wrote: > On Saturday 09 October 2021 15:22:29 Peter Hodgson wrote: > > > Hi John, > > > > Thanks for sharing the drawing. Yes, I would like to get things > > properly drawn when I get the time. > > > > In the mean time....... would you mind having a quick look at the > > revised schematic on the following link to check I have placed the > > capacitors you suggested in the correct place when using the HCPL2631 > > ?? > > > > https://www.purbrookengineering.com/index.php?option=com_content&view= > >article&id=11 > > > > > > I notice on your drawing you have 'Earth' and FGND. What's the > > difference? > > > > Pete > > > That looks better, as long as the opto's are fast enough. Verify that > with a o-scope. And the halscope is not fast enough, use a real one. But > please don't use yellow on white for the signal wires, they disappear in > the pdf. :( > > > On 09/10/2021 18:18, John Dammeyer wrote: > > > Hi Peter, > > > I find it helps to draw a wiring diagram of where things are wired. > > > That’s different from a schematic which just shows how things are > > > connected. > > > > > > For example, I've attached the old schematic of my mill wiring > > > (before I removed the two HP-UHU drives and wired in the quadrature > > > encoder for the spindle into the second Chinese BoB). Note to self: > > > Really must update now that I have AC servos on everything. > > > > > > I have colour codes on there for wiring. But it does not show the > > > actual wiring paths. For example the 24V comes out of the Power > > > Supply and splits in two directions. One to the DIN Rail for the > > > MiniBoB->STMBL drive, the STMBL drive and 24V-16V UHU power supply. > > > From there another DIN rail set of terminal blocks to run power out > > > to the Bergerda Spindle Interface and now the Bergerda interface > > > boards. > > > > > > But the drawing doesn't actually show the DIN rails or wire lengths > > > so there's no way to see if the 24V system has ground loops etc. > > > Not from the Schematic. > > > > > > So I still have to create a new 'mechanical' wiring diagram that > > > shows where rather than how things are connected. > > > > > > John > > > > > >> -----Original Message----- > > >> From: Peter Hodgson [mailto:peterjohnhodg...@gmail.com] > > >> Sent: October-09-21 1:38 AM > > >> To: Enhanced Machine Controller (EMC) > > >> Subject: Re: [Emc-users] Fwd: Rogue Index Pulses > > >> > > >> Thanks Chris, yes, I will change the shielding ground to the > > >> controller end and isolate the case. > > >> > > >> Is it best practice to run the 5v and 12v �grounds� back to the > > >> original 24v power supply 0v? > > >> > > >>> On 9 Oct 2021, at 00:53, Chris Albertson > > >>> <albertson.ch...@gmail.com> wrote: > > >>> > > >>> ?I'll say what Gene said. I'd bet on a groubing issue. The > > >>> schmatic has an error, a groubd wire ismissing and also shows > > >>> random crossing grounds. Run everything back to the power supply > > >>> minus post. > > >>> > > >>> Also you be much better if the sheild was grounded to the > > >>> controller end. Never us a machine and it's mounting bolts as > > >>> grounds. > > >>> > > >>> > > >>> -- > > >>> > > >>> Chris Albertson > > >>> Redondo Beach, California > > >>> > > >>> _______________________________________________ > > >>> Emc-users mailing list > > >>> Emc-users@lists.sourceforge.net > > >>> https://lists.sourceforge.net/lists/listinfo/emc-users > > >> > > >> _______________________________________________ > > >> Emc-users mailing list > > >> Emc-users@lists.sourceforge.net > > >> https://lists.sourceforge.net/lists/listinfo/emc-users > > >> > > >> > > >> _______________________________________________ > > >> Emc-users mailing list > > >> Emc-users@lists.sourceforge.net > > >> https://lists.sourceforge.net/lists/listinfo/emc-users > > > > _______________________________________________ > > Emc-users mailing list > > Emc-users@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > 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, 1940) > 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 > -- Chris Albertson Redondo Beach, California _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
