On Tue, 20 Nov 2012, Przemek Klosowski wrote: > Date: Tue, 20 Nov 2012 17:28:14 -0500 > From: Przemek Klosowski <przemek.klosow...@gmail.com> > Reply-To: "Enhanced Machine Controller (EMC)" > <emc-users@lists.sourceforge.net> > To: "Enhanced Machine Controller (EMC)" <emc-users@lists.sourceforge.net> > Subject: [Emc-users] VFD input > > Not strictly EMC but I am sure people here will know the answer. We all > know that a 3-phase VFD can often be used off one-phase. Since all the > current is then pulled off the one leg of the input rectifier, the standard > wisdom says that you derate the VFD power in this situation by a factor of > 2 or so. > > It occurred to me that since the input circuit should be just a 3-phase > rectifier, it should work to connect all three input terminals together, > and feed that from the single phase. > > Would it work on the VFDs you're familiar with?
It should be noted that the de-rating is chiefly because of the much larger ripple voltage and ripple current in the filter capacitors (100/120Hz ripple frequency vs 300/360 Hz) Peter Wallace Mesa Electronics ------------------------------------------------------------------------------ Monitor your physical, virtual and cloud infrastructure from a single web console. Get in-depth insight into apps, servers, databases, vmware, SAP, cloud infrastructure, etc. Download 30-day Free Trial. Pricing starts from $795 for 25 servers or applications! http://p.sf.net/sfu/zoho_dev2dev_nov _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
