Re: MOT Primary Current Question

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: Gomez Addams <gomezaddams@xxxxxxxxx>


On Jun 12, 2006, at 10:15 AM, Tesla list wrote:

> Original poster: Justin <rocketfuel@xxxxxxxxxxxxx>
>
> Greetings!
>
> I have a rudimentary question that's been nagging me every since that
> pole pig discussion of last week.
>
> Experience and my gut tell me that an open secondary will draw very
> little real current on the primary side.  What I can't figure out is
> *why* that's true because from one POV that primary should be a low
> resistance short circuit and current should be through the roof!

The windings plus iron core gives enough inductive reactance at 60Hz
to keep the open-secondary (aka "magnetizing") current to a minimum.

> Is it the impedence of the coil + core that keeps things from going
> bananas?

Yes.

>   Some sort of magneticlaly induced EMF that opposes the current
> flow?  My gut also tells me that if I simply make a coil out of wire
> and stick it in my wall outlet the current would definitely be there.

Without a big iron core, you'd better believe that's what will happen!

 - B(G)L