On Tuesday 01 November 2016 08:33:39 John Alexander Stewart wrote: > Hi all; > > Back to my CNC lathe project; it has sat dormant for a few years now. > > Opinions wanted: > > The VFD suggests 10a external fuses, plus a line filter. I'm running > this on 240v, over here in North America. > Same here John. NEC wiring & all that.
> Are 10A slow blow 250v glass fuses ok for this application? Is it > overkill to fuse both hot leads, I presume so, but if I'm going to the > bother of putting in 1 fuse holder... Also, I could use class J fuses, > but note that glass fuses seem to be just fine for other workshop > equipment. > > Line Reactors. 10A. Generally a good idea or not really worth worrying > about? I am not using any reactors, and it hasn't caused any problems that I am aware of yet. Circuit breaker is a dual 20 amp IIRC since I'm feeding the vfd from 254 volts, ct grounded at the service. 10A slow breakers are 5+ times the cost of the quick 20's in this neck of the woods. And special order. I am not in steady use yet but have left it running an exercise loop in lcnc for an hour at a time. 1.5 hp rated vfd, 1 hp @ 60 Hz 3 phase motor about 35 yo that I put fresh bearings in. Bought 2 of them at a scrap dealer for a $50 bill. Seems to be good up to 150Hz, or 4500 rpms if the motors fan whine can be tolerated. The lathe is an 11x36 Sheldon with a screw on chuck. :( Got to figure a way to pin that puppy. :) The reactors, AIUI, should improve the power factor, which your electric meter may be sensitive to, and they _might_ reduce your electric bill. I expect you would have to meter it by itself to be able to detect the diff though. > The 3-phase from the VFD will be in a metal braid for shielding, > grounded at the VFD end. The 4-wire cable will have the U-V-W + > ground, weird to ground both the VFD side and the motor, but that's > the way it's done, I guess. I have mine in that blue plastic thats almost flexible, with a separate ground wire to the motor frame from the static neutral at the vfd. > The lathe is an 8x18, Austrian made lathe. Would have loved a Tormach, > but the size of the thing would mean a new house, and *that* gets > expensive. > I hear that, this 11x36 completes my garage, no wasted space if the midden heap is counted. > Thanks - John. > ---------------------------------------------------------------------- >-------- Developer Access Program for Intel Xeon Phi Processors > Access to Intel Xeon Phi processor-based developer platforms. > With one year of Intel Parallel Studio XE. > Training and support from Colfax. > Order your platform today. http://sdm.link/xeonphi > _______________________________________________ > Emc-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-users 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) Genes Web page <http://geneslinuxbox.net:6309/gene> ------------------------------------------------------------------------------ Developer Access Program for Intel Xeon Phi Processors Access to Intel Xeon Phi processor-based developer platforms. With one year of Intel Parallel Studio XE. Training and support from Colfax. Order your platform today. http://sdm.link/xeonphi _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
