> On May 14, 2015, at 4:15 PM, Peter C. Wallace <p...@mesanet.com> wrote: > We found that common mode filters (big ferrite bead around U,V,W) on the > motor leads help a lot. Otherwise you have ~360V square waves driving the > stray wiring and motor capacitance and _nothing_ to limit the peak current of > these fast edges driving into this capacitance to ground. This causes huge > ground bumping of the VFD ground. A common mode choke limits these peak > currents considerably (and is probably built-in in better drives)
The GS2 VFD manual says that if you cannot have a ferrite wrapped on each lead, you can use 4 of them together to enclose the entire motor cable. I don’t have extra wire to do them individually and my wire is a multi-conductor (3 + ground). So I am going to put 4 ferrites together over the whole cable (including ground). I hope that has the same or similar effect. I am wondering if I will see any effect in the amplitude of the generated noise on the spectrum analyzer I have…? -Tom ------------------------------------------------------------------------------ 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
