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Mike Marlow[_2_] Mike Marlow[_2_] is offline
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Default 220VAC vs. 240VAC Saw Motor S.O.T.

Nonny wrote:
"Lee Michaels" wrote in
message ...

"Gordon Shumway" wrote

I'll do my best to simplify the answer.

I think its time for me to explain about 240 current and why it
is so
different from 120 volt service. First of all, it's twice as
big.
Secondly, it'll shock you more. Outside of that, 240 is really
two
120 volt lines coming to your house from different parts of the
globe.
The up and down 120 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 240 volts, while either individual side only
gives
you 120 volts.

This is particularly important to know when buying power
tools --
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 US
generated 120 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. 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 240 and accidentally get two
US-generated
120 volt lines run in by accident, you can get 240 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 240.
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.


Many years ago, I went to electronics school. The guys there
would have howled at this bit of lunacy.

I am trying figure out if you are really funny or just totally
disturbed. Did you write this or get it from someplace?




Haven't you ever heard of a power inverter?


That's a totally different beast. We're talking just about voltage here...

--

-Mike-