Thanks Gene, I just ordered a Rasmi unit that should be able to mount behind the VFD inside the panel (assuming enough depth in the box). Apparently they make them for Yaskawa drives, but my Hitachi has the same bolt pattern. I’ll get it installed and see how it looks. If that checks out, I’ll probably still rewire the grounds to be sure of success. But I’ll take some measurements along the way and see how well it works (or doesn’t).
> On Aug 4, 2020, at 11:42 AM, Gene Heskett <ghesk...@shentel.net> wrote: > > On Tuesday 04 August 2020 09:09:38 andy pugh wrote: > >> On Tue, 4 Aug 2020 at 14:03, Matthew Herd <herd.m...@gmail.com> wrote: >>> I am guessing that the source of the trouble is probably the VFD, as >>> 80kHz seems like a plausible base frequency for driving an AC motor. >> >> Add an input filter to the VFD. They are not expensive. Look on eBay >> for "Rasmi" (one manufacturer, but a good search term) > > Or on this side of the pond, CorCom make's both a single phase and a 3 > phase filter thats a brick wall above 30 mhz, I have one on both sides > of the vfd on the Sheldon. I can see the vfd, but its under 200 > millivolts all the way to the scopes 100+ megahertz bandwidth. > > Cheers, Gene Heskett > -- > "There are four boxes to be used in defense of liberty: > soap, ballot, jury, and ammo. Please use in that order." > -Ed Howdershelt (Author) > If we desire respect for the law, we must first make the law respectable. > - Louis D. Brandeis > Genes Web page <http://geneslinuxbox.net:6309/gene> > > > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
