Okay, I guess I asked the wrong question.

I guess what I should have asked was how the motor speed is controlled by changing the voltage.

In an AC motor, the motor's "synchronous" speed is a function of the AC frequency. I've worked with VFD's quite a bit. But how do you vary an AC motor's speed by changing the voltage?

[This message has been edited by maintenanceguy (edited 10-07-2004).]