On Wed, 28 Jul 2021 at 00:46, Gene Heskett <[email protected]> wrote:
> > Yes, this is an approx. 1984 machine. > > That new? I would have guessed 1934, the year I was born. That means of > making a variable speed motor is ancient tech because its not very > efficient. I think you are maybe thinking of the Ward Leonard set, as used on the early Monarch 10EE, where an AC motor ran a DC generator which, in turn ran a DC motor. That is pretty old-tech, but a DC motor with solid state drive is hardly old-school at all (only the use of field coils is slightly outdated at that motor size) > An AC motor and a vfd should cut the energy bill in half > compared to that. But will have less low-speed torque. Bear in mind that the lathe is geared for 2500rpm and was probably running at 250rpm (steel part 8" dia, carbide tooling) A VFD would be down at 5Hz to achieve that. I think that a DC motor is appropriate here, but probably a PM servo motor would be better. Is this the motor originally supplied with the lathe? -- atp "A motorcycle is a bicycle with a pandemonium attachment and is designed for the especial use of mechanical geniuses, daredevils and lunatics." — George Fitch, Atlanta Constitution Newspaper, 1912 _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
