I've had to replace all of the power cables for the servo motors and spindle on a large CNC wood router that was only 10 years old. This was a machine with Fanuc control and servos. (I think it had a Yaskawa VFD). The encoder cables were higher quality and didn't give problems. It was giving all sorts of weird intermittent alarms mostly for the servos. When I opened up the cable chains, I couldn't hardly believe that it hadn't caught fire. There were broken and exposed and charred wires all over the place. The spindle cable had broken wires in at least a half dozen places. It was a wonder it ran at all. It was a major mess. (Sorry Gene I don't think any of those cables had red insulation.) I think the machine manufacturer cheeped out and didn't use cable chain rated cable or just got a bad batch. We had an identical machine a year older and never had those problems.
Todd Zuercher P. Graham Dunn Inc. 630 Henry Street Dalton, Ohio 44618 Phone: (330)828-2105ext. 2031 -----Original Message----- From: gene heskett <ghesk...@shentel.net> Sent: Thursday, March 16, 2023 3:50 PM To: emc-users@lists.sourceforge.net Subject: Re: [Emc-users] OT: Air cooled router spindle problem [EXTERNAL EMAIL] Be sure links are safe. On 3/16/23 12:44, Leonardo Marsaglia wrote: > I've checked that the terminals are connected well but I didn't check > for the entire cable to be alright. > > I thought about it but I really didn't think such an intermittent > failure could be caused by the cable alone. Do you recommend to > install a new cable just in case? > That depends on how old that cable is, and how much flexing it has endured in its time. And in some instances, what color the plastic used for insulation is. Magenta, aka hot red or hot pink, contains a chemical I can't name but it destroys the copper in the wire by converting it to a fine, rust colored powder that may, or may not, properly conduct electricity. That color is most often found in two-way radio microphone cords as the connection to the tx button, or today, more commonly as the outer jacket of a sata drive cable in your computers. In either case, the failure rate by the time its 5 years old, is well up the far end of the well known bathtub curve. I long ago changed all of mine out for any color but hot red/aka magenta. End of drive errors. I have serious doubts that is the problem in this case, since the currents involved are definitely capable of starting a noticeable fire. But a hand, run along the length of the cable, looking for hot spots when the failure is in evidence might not be a bad idea. Or better yet, tracing the wire with an IR thermometer or infra-red camera. > El jue., 16 de marzo de 2023 13:37, Todd Zuercher > <to...@pgrahamdunn.com> > escribió: > >> Have you checked your cabling between the motor and VFD? And please folks, take a break on the mail server, and trim your posts down to the context of your reply. Cheers, Gene Heskett. -- _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
