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Re: No sound-inputs but sound recording FMIT




I wrote:
> Induction motors can function as generators.  You just need to connect
> them to an appropriate AC source and drive them above synchronous
> speed.

Gene writes:
> Yes, there is that exception, they need an excitation current, true,
> but in that case they make excellent brakes as they don't like
> spinning above synchronous any better than they like running below it.
> And with enough dc current you can come pretty close to stopping them
> dead in their tracks. Certainly within one revolution.  But the
> armature is soft, and its not possible to maintain the magnetic field
> from its shorted turns armature long enough to extract any output
> power from it for more than a few milliseconds.

That's not what I mean.  Hook an induction motor to utility power and
drive it above synchonous speed.  It will power *to* the network.

When you put DC current through the field of an induction motor to brake
it you are also using it as a generator.  It's just that all the power
gets dissipated in the armature.
-- 
John Hasler 
jhasler@xxxxxxxxxxx
Elmwood, WI USA