I have been fighting the exact same problem for some weeks now. I did all the screening things and earth things and everything else I could. I just discovered that the frame of my lathe was not earthed and the motor is mounted to the frame. Although the motor was earthed via the VFD cable it was still floating. After I earthed my frame to the controller star earth point my noise went away. Now I have to discover if I popped my Mesa 7i76 encoder input.
------ Original Message ------ From: "Erik Christiansen" <dva...@internode.on.net> To: emc-users@lists.sourceforge.net Sent: 2015-05-12 11:54:21 Subject: Re: [Emc-users] If there's one thing I hate, all the noise, noise, noise, noise >On 11.05.15 23:14, Tom Easterday wrote: >> I will do that tomorrow. I wonder if using this tape to shield >> unshielded wire, like my VFD to motor cable, would work….? >> >>http://www.cesco.com/b2c/product/9770?utm_source=google&utm_medium=cpc&utm_campaign=shopping&scid=scplp2640202&gclid=CMTdkaSbu8UCFZeDaQodlRgAHQ > >That or copper tape can be used for shielding, but still forms a coiled >inductor back to the cable ends, unless contact between turns is very >good. Can you run two tape lengths longitudinally, overlapping their >edges around the cable diameter, and stitching them into a >tube with frequent solder joints? Minimum impedance, at RF, back to >your >star earth (from one end only) has to be good, after shutting it in. > >Or, do you have some Al or Cu tubing in the junkbox, that you can bend >after pushing the cable through? If it's to hand, it's something you >can >do without waiting for deliveries, and should work at least as well. >If it's primarily magnetic coupling, then steel tubing might be better. >Experimenting with a (mostly) closed steel box around the computer can >help determine that. > >The power radiated is proportional to the open area between the two >power conductors. If they are twisted, e.g. one turn per inch, then >that >is minimised, and there is less work for shielding to do. > >My mini-ITX mobo is powered by a picoPSU, so can run off a 12v battery. >Thus isolating power entirely, and disconnecting the parport or other >I/O >would allow checking whether Axis still plays up - proving that it is >radiated EMI. That may be hard to do there. > >It'll be very interesting to hear what finally cures it. > >Erik > >------------------------------------------------------------------------------ >One dashboard for servers and applications across >Physical-Virtual-Cloud >Widest out-of-the-box monitoring support with 50+ applications >Performance metrics, stats and reports that give you Actionable >Insights >Deep dive visibility with transaction tracing using APM Insight. >http://ad.doubleclick.net/ddm/clk/290420510;117567292;y >_______________________________________________ >Emc-users mailing list >Emc-users@lists.sourceforge.net >https://lists.sourceforge.net/lists/listinfo/emc-users ------------------------------------------------------------------------------ One dashboard for servers and applications across Physical-Virtual-Cloud Widest out-of-the-box monitoring support with 50+ applications Performance metrics, stats and reports that give you Actionable Insights Deep dive visibility with transaction tracing using APM Insight. http://ad.doubleclick.net/ddm/clk/290420510;117567292;y _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
