RE: poor power factor coils

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Steve Conner" <steve.conner-at-optosci-dot-com> 

 >WIth my microwave oven transformers, 2 of them almost shorted on
 >their outputs tends to cause my 35 amp breaker to blow. However it almost
 >never blows the 16 amp fuse.  WOuld this be because of the high peak
 >currents from a poor power factor?

Sort of all of those things ;) Firstly, a fuse has a different response
characteristic to a breaker. The reason being that the fuse has to heat up
before it can melt, but the breaker is operated by magnetic forces that work
instantly. A 16 amp fuse will stand 32A or more for a minute or so, whereas
a 35A breaker usually pops at 35A no matter what. So you often see overloads
popping a breaker before they blow a fuse.

Secondly, MOTs have a poor power factor because of the way they're designed
(they draw lots of magnetizing current when unloaded)

Thirdly, the output of the bank being "almost shorted" will lead to an even
worse power factor. There's nothing dissipating any real power so mostly
reactive power is flowing.

If you draw out a nice long arc, things may improve ;) Or you can ballast
your MOT bank with several toaster ovens or electric heaters.  Choose the
ballast to draw less than 35A -at- 120V, then your breaker will never blow.

16A -at- 120V is 1.9kVA, you can easily get 3-4 foot arcs off a Tesla coil with
this amount of power.

Steve C.