On Tuesday 02 January 2018 12:50:24 Les Newell wrote: > Hi Gene, > > Are you sure your drive isn't shutting down due to over voltage rather > than over current? The only way to brake a 3 phase motor without > pumping power back into the bus is to use DC braking. DC braking can > cause rotor heating problems on machines that decelerate often. > This is true, so I've had to program currents for dc braking as well as for how long. The only place where I might cause a rotor overheat might be with a big tap it can't pull in one stroke and "pecking" the g33.1 with an incremental depth. I've not tried a tap that big yet. Generally I've used a g76 for that as I have tools small enough to make a 1/2" 50 tpi internal thread, which I had done several times but usually on TLM, which has a dc motor setup all the way. I need to make a tap holder to fit into an axa tool holder yet. That will likely not get done till I need it. :) When will I need it is the $64k question. :) > Les > > On 02/01/2018 17:42, Gene Heskett wrote: > > And they are full 4 quadrant controllers, so within reason no > > braking R's are required. Laying on the table, I can reverse a 1hp 3 > > phase motor turning 2400 revs, fast enough to make it jump 3" up in > > the air with one of those 1.5 horse rated, $128 on ebay controllers. > > Installed on a lathe with an 8" chuck, I have to program it to take > > a bit over a second to reverse that 8" chuck from 200 revs because I > > have to set a limit of the decel current else it self protects with > > a total shutdown. So I am a happy camper until I decide to put a 5 > > hp on my old Sheldon. Can I do rigid tapping? Yup. I have hal code > > to tell me how much overshoot occurs at the bottom of the hole, so I > > don't break taps hitting the bottom of a blind hole. > > > > Cheers, Gene Heskett > > ---------------------------------------------------------------------- >-------- Check out the vibrant tech community on one of the world's > most engaging tech sites, Slashdot.org! http://sdm.link/slashdot > _______________________________________________ > 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) Genes Web page <http://geneslinuxbox.net:6309/gene> ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
