[GreenKeys] Machine speed and VFDs

[Richard Knoppow]

    Both kinds of motors were used in phonographs, induction 
motors in cheaper ones, hysteresis synchronous motors in more 
expensive ones. Also as the capstan drive in tape recorders. 
These are all fractional HP motors.

On 9/3/2018 5:24 PM, Jim Haynes wrote:
> There's a thing called the "hysteresis synchronous motor".  If 
> you look at
> the motor in a Teletype machine you'll see that the speed is 
> marked 3600
> RPM and that the rotor appears to be a solid piece of metal.  
> It's been
> a long time since I had to take the AC machinery course in EE 
> school, and
> I don't think that kind of motor was covered, but I can assure 
> you it is
> a real synchronous motor, not an induction motor that has some slip.

-- 
Richard Knoppow
1oldlens1 at ix.netcom.com
WB6KBL