yea , a simple transformer and rectifier and cap block is all you need , never mind all these fancy switched mode stuff
On 7 August 2014 12:19, Gene Heskett <[email protected]> wrote: > On Thursday 07 August 2014 04:57:50 David Armstrong did opine > And Gene did reply: > > Gene > > go for the highest voltage the drivers will take, i also tend to buy > > the drive that can take 60v+ , i run mine mostly at 48v or 60v , it > > makes so much of a difference it's worth it > > > > Dave > > When I last "rebuilt" the mills control box, I had not fully understood > that, and there was an ultra cheap medical grade 28 volt nearly 12 amp > supply at all-electronics I could get for a $30 bill. But for reliable > duty, I find I can't ask it to move, with the ball screws in the XY, more > than about 18 ipm. When I built the same box for the lathe, I raided the > midden heap and was able to get a choke input put together that made > around 37 volts. That extra 9 volts on the z motor, which is geared down > 2/1 to the ball screw, allows it to march right along at 60ipm dead > reliably. The change in performance seems all out of proportion to the > change in voltage and its amazing to see the damper on the Z motor looking > like its turning well over 1000 rpms. > > Find suitable psu components to cobble up the higher voltage supplies is > always a frustrating task. So for an input choke on the lathe, I have the > primary well isolated, and am using the 5 volt winding of a filament > transformer as the choke. At around 6 amps load, its likely near magnetic > saturation but is aided by running the 8 wire X motor is series mode since > its speed is quite sufficient to do a G76 threading operation at 6 or 7 > hundred rpms even in that mode. > > But the mill, with its 4 motor load, needing 2x the amperage, will > probably wind up with another analog psu external to the box. The 28 v > unit in it, also has a 5 v logic supply output that runs the BOB, so if I > remove it, I'll need to find a substitute for that. Those are commodity > items though, and not a problem to source at reasonable $. All I need is > time & luck at finding the power iron. > > Choke input filtering is much easier on the transformers as they can > deliver more current for the same amount of heating, and the unregulated > output is much better regulated. > > With several thousand mf on the output side, these drivers & motors seem > to love it. > > 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> > US V Castleman, SCOTUS, Mar 2014 is grounds for Impeaching SCOTUS > > > ------------------------------------------------------------------------------ > Infragistics Professional > Build stunning WinForms apps today! > Reboot your WinForms applications with our WinForms controls. > Build a bridge from your legacy apps to the future. > > http://pubads.g.doubleclick.net/gampad/clk?id=153845071&iu=/4140/ostg.clktrk > _______________________________________________ > Emc-developers mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-developers > ------------------------------------------------------------------------------ Infragistics Professional Build stunning WinForms apps today! Reboot your WinForms applications with our WinForms controls. Build a bridge from your legacy apps to the future. http://pubads.g.doubleclick.net/gampad/clk?id=153845071&iu=/4140/ostg.clktrk _______________________________________________ Emc-developers mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-developers
