On Tuesday, 26 April 2022 15:59:16 EDT Todd Zuercher wrote: > Gene, > > If you think you could fix it I'd be more than willing to send the old > drive to you to work on it. I am certainly not a CET, but there isn't > any obvious failures from something blowing up or overheating, and the > caps show no visible swelling or leaking. > > The drive had been acting up for the past couple months. When the > machine would be first powered on (throwing disconnect) the drive > would not "turn on" right away "Power" LED on the front of the drive > would not light up, even though the drive had power on all 3 phases. > If the machine was left turned on for an extended period of time (a > half hour or maybe more) eventually the drive would power up and work > correctly. This drive has no display other than a row of 5 LEDs for > fault and power indication. None of the alarm indicators have ever > have shown anything. Last week it stopped working completely. We are > of the opinion the problem probably likes in the low voltage board and > won't be easily found. > That you probably could find with the KC-MO meter. I'd bet a beer its still a capacitor, probably a 16 volt that was used in a 5 volt circuit, and 5 volts is not enough to keep them "formed" so they gradually lose capacitance.
But if on a wave soldered board full of surface mounted stuff, will take longer to fix, as I never invested in the soldering tools that took. And a delicate touch. Back when we had about 15 of the DVC-PRO Panasonic machines at WDTV, I used to shotgun the caps on 2 to 4 boards a day. 40+ caps about the size of a lead pencil erasor or smaller. Great machines when they worked, but panasonic made their own caps, no one else made them small enough. I retired 20 years ago this coming June because my back was giving me hell from being bent over doing that thru a big magnifying lens and at 67, it looked like I was stuck doing that 6 or so hours a day till we converted to digital high def, then 6 years yet in the future. What you need to do, is see if you can find a local CET. We are a mite rare. I can and have drove over to Dayton as Venture MFG is or was behind the airport, and they made (or imported) the bigger satellite dish steering jacks I used on the dish mounts I made at WDTV, but its a looong half day trip each way. Often past last call by the time I rolled back into the driveway here in WV. Somebody at the National Electroncs Association HQ in Omaha might be able to tell you a phone number or two. Ask for Ronald Crow if he still lives. He co-signed my Certificate in 1972. 50 years ago now. > Todd Zuercher > P. Graham Dunn Inc. > 630 Henry Street > Dalton, Ohio 44618 > Phone: (330)828-2105ext. 2031 > > -----Original Message----- > From: gene heskett <ghesk...@shentel.net> > Sent: Tuesday, April 26, 2022 2:33 PM > To: Enhanced Machine Controller (EMC) <emc-users@lists.sourceforge.net> > Subject: Re: [Emc-users] Hight Frequency VFD > > [EXTERNAL EMAIL] Be sure links are safe. > > 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.<https://nam04.safelinks.protection.outlook.com/?url=http%3A%2F%2 > > F > > www.pgrahamdunn.com%2Findex.php&data=05%7C01%7Ctoddz%40pgrahamdun > > n > > .com%7Cd60b8c8acfae46f7227408da27b35a43%7C5758544c573f47cebee96c3e080 > > 6 > > fb43%7C0%7C0%7C637865948772332793%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4 > > w > > LjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7 > > C > > &sdata=w5Y%2BJICZjBhcDKy49wPwqC5fydGaygI2lIp9i5jwrX8%3D&reser > > v > > ed=0> > > 630 Henry Street > > Dalton, Ohio 44618 > > Phone: (330)828-2105ext. 2031 > > > > > > _______________________________________________ > > Emc-users mailing list > > Emc-users@lists.sourceforge.net > > https://nam04.safelinks.protection.outlook.com/?url=https%3A%2F%2Flis > > t > > s.sourceforge.net%2Flists%2Flistinfo%2Femc-users&data=05%7C01%7Ct > > o > > ddz%40pgrahamdunn.com%7Cd60b8c8acfae46f7227408da27b35a43%7C5758544c57 > > 3 > > f47cebee96c3e0806fb43%7C0%7C0%7C637865948772332793%7CUnknown%7CTWFpbG > > Z > > sb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0% > > 3 > > D%7C3000%7C%7C%7C&sdata=Yub5sJiuOs%2Bi3aQMUDrbdHD5hrqb1MUbc4ePh7m > > c > > yhk%3D&reserved=0 > > . > > 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://nam04.safelinks.protection.outlook.com/?url=https%3A%2F%2Flists > .sourceforge.net%2Flists%2Flistinfo%2Femc-users&data=05%7C01%7Ctodd > z%40pgrahamdunn.com%7Cd60b8c8acfae46f7227408da27b35a43%7C5758544c573f47 > cebee96c3e0806fb43%7C0%7C0%7C637865948772332793%7CUnknown%7CTWFpbGZsb3d > 8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3 > 000%7C%7C%7C&sdata=Yub5sJiuOs%2Bi3aQMUDrbdHD5hrqb1MUbc4ePh7mcyhk%3D > &reserved=0 > > > _______________________________________________ > 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
