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Mike Marlow[_2_] Mike Marlow[_2_] is offline
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Default 220 V table saws and ground


"Nonny" wrote in message
...

"Robert Bonomi" wrote in message

Since there's been a lot of great thought posted here about voltage,
resistance, light output and longevity, I thought I'd go ahead and give a
general explanation of electricity for those of you all who don't really
understand it fully. It's a repeat of a post to another newsgroup, but of
equal relevance here. Grin

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. On 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- 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 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, with 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 US-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



Finally! An authoritative explanation of all those things that have been so
confusing for so long!

--

-Mike-