Thanks guys, That's that then, controllers in a cabinet again!
Gene, Having worked on installing mainframe computers for many years I do normally use star earths for anything electronic and my previous controller cabinet certainly has this - a central bolt - for all the stepper control stuff and the wiring for each stepper was done in shielded cable with the shielding tied to the star point and the shielding extended right up to, but not tied to the motors.. The spindle - a mains high speed brush motor, however was separately fed via a thyristor speed control board from a relay in the control cabinet. The motor has suppressors across the brushes and to earth and all the earths on this side of things were tied to an earthing point on the machine and so I suppose that there is a vague possibility that interference could have tracked back through the mains wiring although here again, the mains to both parts was fed from the same wall socket. However, I am skeptical of this as the only axis that was affected was the Z-axis - the one nearest the spindle motor. I tried several spindle motors without curing the problem ( the axis would very slowly feed down into the work ) and only solved it when I changed to a synchronous-type of motor. Maybe there was something amiss with the stepper which made it susceptible to interference - I don't know. Ian _______________ Ian W. Wright Sheffield UK ------------------------------------------------------------------------------ Come build with us! The BlackBerry® Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9-12, 2009. Register now! http://p.sf.net/sfu/devconf _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users