Steve Blackmore wrote: > My lathe has a 100 slotted disc on the spindle, with one opto switch > fitted so far, the slot for that is longer than the others and gets me > one pulse per rev. It works fine to 3500 rpm as a rev counter. I want to > add two more opto's to get me an A and B channel to enable spindle > control for threading under EMC. Motor reverse is essential too. > > Are there any specifics as to the positioning of the opto's in relation > to each other? Do they need to be only a few slots apart, or more? I > think that the A & B need to be 1/2 slot out of sync - is that correct? > > They need to have a 90 degree phase relationship - that's the definition of "quadrature". So, just as one sensor is dead center in the slot, the other should be right on the edge. The actual spacing in number of slots between the sensors is not important. But, in any case, they should be some full slot multiple, plus 1/4 of a slot, apart.
Jon ------------------------------------------------------------------------------ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
