Single Phase Induction Motor

[gawnieonengineering]

When the centrifugal switch operates on a single phase induction motor and switches off the auxiliary starting components and the motor is driven by an engine past 0 slip (so as a generator) do the auxiliary components have any affect on the operation of the generator?

 

[waross]

What are the "Auxiliary components?"

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[gawnieonengineering]

In a capacitor start induction motor, there are auxiliary capacitor and an auxiliary winding.

 

[waross]

Oh, you mean the starting winding and the starting capacitor.
When they are out of the circuit they are out of the circuit and have no effect.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[MiketheEngineer]

Unless something is wrong in the circuit - can happen!!??

 

[Compositepro]

If you are going to use the motor for a generator, then remove or disable the centrifugal switch and capacitor.

 

[jraef]

The centrifugal switch is closed when starting, it opens at speed. So if it was ALREADY open by the time you over drive the motor, then it remains open and the start winding and cap are still out of the circuit.

If on the other hand you bring the motor up to speed with the engine and only energize it AFTER you get to the over drive speed, then when it is first energized, the start winding and cap will be briefly in the circuit. Not really sure what that would mean, but I agree with Compositepro, if that's the way you are going to do it, just remove the centrifugal switch and cap, you don't need them and it's just something else to fail.

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[ScusaMe]

Jeff,

How do it do dat ?

"If on the other hand you bring the motor up to speed with the engine and only energize it AFTER you get to the over drive speed, then when it is first energized, the start winding and cap will be briefly in the circuit."

As the Centrifugal Switch is not electrically operated ... but instead is mechanically operated by the centrifugal (centripital) force resulting from the rotation of the the motor shaft, and allowing that the engine drove the de-energized motor up to speed starting at zero rpm..... then the switch would be closed initially and would open as the rpm passed thru the value at which the switch is designed to open ... usually below run speed .....

That being the case ... the switch would be open when the motor is energized at the attainment of or above the run speed ....

n'est-ce pas?

'ScusaMe