Heh - and it "should" fit in the available space :)
On Tue, Apr 26, 2022 at 1:35 PM gene heskett <ghesk...@shentel.net> wrote: > On Tuesday, 26 April 2022 11:38:47 EDT Todd Zuercher wrote: > > Anyone know a good place to purchase a high frequency VFD? We had the > > drive in one of our CNCs die. The old drive was a HSD DS15000. The > > spindle is an 18kw 24000rpm 4pole HSD router motor. > > A 2 pole motor should run 24k revs on a 400 hz drive. 30k on 500 hz. > A 4 pole then should run 12k on 400hz, and 30k on 1000hz. Since motors > are made in pole counts of a power of two, a 4 pole should run at 24k at > 800hz. > > > The old drive is > > rated for 1-1000hz and that seems to be the problem, all of the off > > the shelf drives I can find are limited to output frequencies less > > than 500hz which would limit our spindles top speed to only 15000rmp. > > Our machine builder quoted us for a Yaskawa V1000 drive with 1000hz > > firmware (model# VU4A0038FAA-134) that they do have in stock but they > > are marking up their price to more than double the normal list price > > for that drive. Every other place I've checked with so far are > > quoting us months long lead times for that drive. > > Putting on my Certified lectronics Technician hat, how about fixing that > drive? > > Unless the motor has developed shorted turns, the inductance of all 3 > windings s/b within 5% of each other, mucking up the impedance of a > winding, which might blow some output bugs, the most common failure is > the big filter caps which most chinese drive makers claim should be > changed at 5 year intervals due to ESR growth. That of course leads to > heating and is self feeding until the cap vents or even explodes. They > are what stores the relatively slow 60 hz rectified power, making it > available at the high frequencies these motors need. > > So, whats wrong with that drive? Open it up and take a look, Todd. Any > sign of a bulged top/bottom or even a whitish leakage condemns them to > replacement with fresh ones, probably from the capacitors orginal maker. > The original vendor of the drive may have them too but his will likely be > as old as the ones you're looking at, so go to the capacitor maker, > they'll be fresher. > > If you have an ESR meter, those should certainly read, with a 4 terminal > measurement, well under half an ohm which I'd call instant grounds for > replacement. .1 ohm or lower would be even better. 2 lead measurements > will swamp out at much higher readings because of the lead ohmage. A 4 > lead measurement sends the exitation signal down one set if leads, and > reads the result from another set of leads, both leads hitting a single > connector per src/load, so they only read the capacitor, not the test > leads. > > Such an ESR meter should be in your kit Todd, but lock it up when not in > use, they aren't $175 cheap like the two lead version made by a guy in > KC-MO I've used for nearly 4 decades now in lower powered electronics. > > Its literally as useful as sliced bread or bottled beer on the test > bench. > [...] > > ask nicely and then maybe they might sell you a drive with the > > "special" HF firmware. > > You've already got one, fix it. For 20% of a new ones cost. Or less... > > > Todd Zuercher > > P. Graham Dunn Inc.<http://www.pgrahamdunn.com/index.php> > > 630 Henry Street > > Dalton, Ohio 44618 > > Phone: (330)828-2105ext. 2031 > > > > > > _______________________________________________ > > Emc-users mailing list > > Emc-users@lists.sourceforge.net > > 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, 1940) > If we desire respect for the law, we must first make the law respectable. > - Louis D. Brandeis > > > > > > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > -- Addressee is the intended audience. If you are not the addressee then my consent is not given for you to read this email furthermore it is my wish you would close this without saving or reading, and cease and desist from saving or opening my private correspondence. Thank you for honoring my wish. _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
