On Tuesday 30 January 2007 13:34, alex wrote: >Xylotex drives are not optoisolated, which may cause noise problems, >which I experienced.
I haven't, Alex. My cabling is short, with cpu, psu and and oak box in tunnel form, fans in both ends pushing and pulling the air through the box, all on the same 20" wide shelf high above the mill, with the motor cabling being longer at about 6 feet, and my motor cabling is shielded with the shields grounded at the ground point of both the board and its supplying psu. No noise problems that I've ever detected. The motor cabling I used is actually a microphone cable called star-quad, 4 conductors, mildly twisted, inside a metalized mylar sheath which is covered by a 98% or so coverage of silver-plated copper shielding braid. Conductor size is 22 gauge, apparently heavy enough. Since the mill if grounded through its third pin power plug, and everything is plugged into the same duplex to 6plex adaptor, I didn't make a ground loop by grounding the motor end of the shielding to the mill. >Also speed is limited due to a voltage limitation of 24 V. Actually, its 30 volts. The chip is rated at 35, but with spikes in such a circuit, be cautious... My home brewed monster (at least 15 amps) psu measures around 29.3 volts on an average day. >I use Geckos 201 now and happy - speed is high and no noise. Motion is >extremely smooth. >They cost more, though. Yes, particularly after the interfacing and motors are added in. Many of today's parport implementations are not capable of sinking the 16ma drive the opto's in the gecko 201 need so booster buffers may be required. The xylotex kit, at about the cost of 3 gecko 201's, gives one 3 262oz motors and all, more than adequate for micromill up to X2 stuff. Above that mill size (X3's and up), gecko's and 497oz motors would be justified. I may do exactly that next summer, with an X3. That is an appetizing machine for an amateur like me, but the screws aren't ball screws either. But first I have to build a new garage for it (or the woodworking tools) to live in. Sawdust and metalworking stuff are mutually exclusive if you want to control rust on the metal tools. -- Cheers, Gene "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) Yahoo.com and AOL/TW attorneys please note, additions to the above message by Gene Heskett are: Copyright 2007 by Maurice Eugene Heskett, all rights reserved. ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys - and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
