On Tuesday 23 August 2016 07:02:33 andy pugh wrote: > On 23 August 2016 at 11:55, andy pugh <[email protected]> wrote: > > For gear tooth detection you probably want > > http://www.ebay.com/sch/i.html?_from=R40&_trksid=p2050601.m570.l1313 > >.TR0.TRC0.H0.XATS667.TRS0&_nkw=ATS667&_sacat=0 > > Though this one gives speed and direction. > http://www.digikey.com/product-detail/en/allegro-microsystems-llc/ATS6 >05LSGTN-S-T/620-1560-1-ND/4825351 > > LinuxCNC would probably need to be educated in how to use the > direction data, though.
First, it would have to show ME how to detect it. Those waveforms are perfectly symmetrical looking to me. I'd much druther use an ABX quadrature setup, it never loses a single edge. I think I'd have to glue an extra piece of iron to match the height and width of a tooth for the index. And offset one of the 667's a bit sideways so the X only saw the extra piece. Getting glue to stick on that nearly 6 decades of oil soaked metal gear might be a problem. So would disassembling it to get a pair of 0-80 holes drilled and tapped in the side of a tooth to hold an extra 'flag'. I'll have to take a wee inventory to see how much clearance there is to the right of big backgear drive gear on the spindle. It seems a little crowded. 1/4" and small change, maybe. OTOH, the index could be on the rear of the spindle just as easily except for making a 2nd mounting bracket and flag. One could grind a groove in the face to detect. Ideas, too darned many... Not enough time in a day in these old bones. That huge toroid I thought was a 2/1 isolation transformer? Its a 1/1 isolator, good for 39 amps CCW. Meaning that variac will be at maximum current at 1/2 scale or less. So I may leave it out except that makes its DC ground hot.. I need to drill & tap a heat sink for the bridge, and find some 1/4" clear, flexible water hose for dumping the coil heat into a bucket of water, and figure out how many of those 6800 uf's at 63 volts I need to parallel for filtering. As for the startup protection, 2 ea 24 volt ice cube relay coils in series with their 10 amp contacts paralleled in each relay, but the contact bank of each relay in series with the load ought to be startup lag enough. That will give around 30 to 34 volts at the hard switch-on time as I've run those 24 volter's on 17 volts, 100% reliably. In other words, it has not yet been powered up. With decent weather tomorrow, maybe. 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> ------------------------------------------------------------------------------ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
