Jim Adney writes:

On 11 Nov 2004 08:08:07 -0500 Sam Goldwasser
wrote:

Jim Adney writes:

On Tue, 9 Nov 2004 16:41:01 -0500 "Charles Schuler"
wrote:

Disassemble the motor and just take in the rotor, so that they don't
have to do any significant work.

IF, it's a wound rotor motor. Most ac rotors are of the squirrel cage
variety.

I was wondering about that. Wouldn't a squirrel cage motor still have
the same magnetic properties? I'm not sure, but I'd bet that such a
rotor would still pass the growler test, but it's hard to imagine a
squirrel cage rotor with a short in it, which, I believe is what the
OP asked about.

By definition, a squirrel cage rotor is all shorts.

Right, but so is a regular commutator rotor. The only difference, I
think, is that the squirrel cage rotor is wound with much more rugged
"wire."

Nah. A commutator motor happens to be shorted but that is a byproduct
of how it's wound, not a requirement. A squirrel cage rotor is a bunch
of copper bars embedded just under the surface of a solid steel rotor
running length-wise. They are shorted at the end plates. Since these
are induction motors, they depend on the current flowing in the bars
as the secondary of a transformer to provide the torque.

For brush-type motors, current is applied to the rotor windings via the
brushes. It's possible to build such a motor without "shorted" windings.

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