Re: [CAD_CAM_EDM_DRO] Re: why not just change the motor?

jlsmith269 wrote:

>let me show my ignorance... what, exactly, makes a 3ph different? if
>it's cap and windings, can't the 3ph be rewound to 1 ph?
>
>

3-phase motors have no starting circuit. They just have the 3 sets of
windings. Single phase motors need a starting circuit to make sure
they begin turning the right direction. That needs a speed sensor
(usually a centrifugal switch) to shut off the start circuit when the
motor reaches nearly operating speed. There are other ways to do
it, such as potential relays and electronic starting controls.
There are no capacitors, either, on a 3-phase motor.

Yes, a 3-phase motor could be rewound for single phase operation, but
even wound as a capacitor start/capacitor run motor, it would not develop
as much power or run as smoothly as a 3-phase motor.

The vibration of single phase motors has been a big problem to a
number of machine retrofits I've heard of in the past few years.

Jon