Electricity, explained:

I think its time for me to explain about 220 current
and why it is so different from 110-volt service.
First of all, it's twice as big. Secondly, it'll shock
you more. Outside of that, 220 is really two 110 volt
lines coming to your house from different parts of the
globe.

The up and down 110 comes from the northern
hemisphere, and the down and up version comes from
below the equator. Without trying to get technical, it
all boils down to the direction water flows when it
goes down the drain. In the top of the earth, it goes
clockwise, while on the bottom of the earth it goes
counter clockwise. Since most electricity is made from
hydro dams, the clockwise flow gives you an up and
down sine wave, while the counterclockwise version
gives you a down and up sine wave. Between the two,
you have 220 volts, while either individual side only
gives you 110 volts. This is particularly important to
know when buying power tools as to which side of the
globe did they come from?

If you get an Australian saw, for instance, it will
turn backwards if connected to a U.S.-generated
110-volt source.

Sure, you can buy backwards blades for it, but that
is an unnecessary burden. Other appliances, like
toasters, cannot be converted from Australian electricity
to American electricity, without horrible results. I knew
one person who bought an Australian toaster by mistake and
it froze the slices of bread she put in it.

If you wire your shop with 220 and accidentally get two
U.S.-generated 110-volt lines run in by accident, you
can get 220 by using a trick I learned from an old
electrician. Just put each source into its own fuse
box and then turn one of the boxes upside down.
That'll invert one of the two up and down sine waves
to down and up, giving you 220.

..DO NOT just turn the box sideways, since that'll give
you 165 volts and you'll be limited to just using
Canadian tools with it.

I hope this clears everything up.