On Thursday 10 December 2020 07:50:23 Sven Wesley wrote: > Den ons 9 dec. 2020 kl 17:41 skrev Sven Wesley <svenne.d...@gmail.com>: > > Maybe my intentions have been unclear and now I'm a bit confused. > > The drives provide a high signal on one pin when they are working. > > If they fail the pin goes low. My initial thought was to connect all > > four pins to one input on the 7i96 and configure it to trigger a > > software stop. Like Gene proposed, shouldn't it work with all wires > > to one input with a diode in series on each pin? > > > > Best regards, > > Confusedius > > Sorry if this is a double post, I believe my attachment was too big > and the post was blocked. > I just realized my own mistake. I can't wire them like I suggested. I > could probably wire all four to one input without the diodes but then > I would never see which one that actually fails (red warning LED on > every drive). All will ground if one fails and then all will fail. I > mean, it would be OK but less optimal. The drivers I have are not bidir, so tying them all in parallel does not fault the others but it would defeat the diode and led isolation, meaning you would still need to eyeball them to determine which one.
By grounding the - terminal of each drivers error out, putting an led from the 5 volt line, along with a 2.2k to limit led current, to the + terminal of the error out, you get a tally available where you can see it, and put a signal diode polarized so that the input to linuxcnc is brought down to half a volt when that driver faults, you could have a large number of fault srcs feeding one input to linuxcnc. Any of them could then trip motion off (F2) and stop the machine. In my case, that shuts off the SSR's controlling motor power, give the psu's time to do a fade to zero which resets the fault, but I've still got the fault notice sitting on the axis screen. So I wait till the display on the vfd goes dark, remove the tool holder so there's room to rehome the machine, hit F2, give the psu's time to wake up and rehome it. Put the tool holder back on the post and go looking thru my code for the mistake. Using a 7i90, I have lots of gpio inputs, and in this case used separate input connections so I could use a video advisory that names the source of the fault. > Would it be possible to use optocouplers and serial to parallel adapt > the wiring? I hope my attached image makes sense but please see it as > a suggestion. I also found a sketch of the internals of the Bucck > board, hope that helps. > What do you electro ninjas think? That is not how I would do it. But, I'll also state that my way is not the only way, There are (N-1)! ways to do it where N is the number of inputs you need to smunch into one wire to stop LCNC, and ! is the factorial symbol. And could be expanded to handle more fault sources easy enough as long as they all worked alike. With "work alike" defined as turning on an isolated switch when it faults. Take care Sven. 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) 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
