Re: [CAD_CAM_EDM_DRO] What kind of motor should I use?

Raymond Heckert wrote:

> The cast rotor bars probably wouldn't stay in their slots at much over 300%
> of their rated r.p.m. The 400Hz aircraft instrument motor is actually
> designed to operate at 400 Hz, the common frequency used on military and
> some "civie" planes. They use 400 Hz because all components can be
> substantially smaller (lighter) than those of our 60 Hz world.

This discussion went on last year either here or on R.C.M. and there was
someone in England stating that a furniture shop had 2 diesel generators
rewound to produce 400 and 800 Hz power, and they used standard motors
rewound for the higer frequency. They started their motors on 400 Hz and
then switched them to 800 Hz, then shut off the 400 Hz generator.
He seemed to imply that these were still 2 or 4-pole motors, so they'd
be running at 24,000 or 48,000 RPM! I was pretty skeptical, to say the
least!

> P.S. don't try to run the 400Hz at 60Hz...The magnetics won't stand for it!

You have to reduce the voltage by a factor of 60/400, so a 208 V motor
would be run at 31 V, and you would not get much power out of it.

Jon