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Jimmie D
 
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Default Double Pole Circuit Breakers


"~^Johnny^~" wrote in message
...
On Fri, 23 Jun 2006 08:11:40 -0700, ~^Johnny^~
wrote:

On Fri, 23 Jun 2006 13:22:41 GMT, (Doug Miller)
wrote:

100A at 240V -- and, as noted above, if only 120V loads are in use, the
total
current draw is (up to) 200A at 120V.



The power consumption is equivalent to 200A at 120V,
but only 100A are flowing. Kirchoff's Law will not
be violated!

Currents in series do not add; =voltages= add.
It's still 100A at 240V.


Better yet,
Look at it this way: If I hang ten 12V lamps in series across a 120V
line, and each lamp is 120 watts, am I pulling a total of 100 amps?
I am not! I am drawing ten amps! Each lamp gets 12V at 10A. 100A
doesn't ever flow, anywhere in the circuit. But I'm still consuming
1200W: 120V at 10A, _NOT_ 12V at 100A. If the lamps were in
parallel, they would require 100A at 12V. But they're not. That's a
load calculation only.

An Edison circuit is just a 240 volt circuit with a grounded
center-tap. In theory, if loads are balanced, the neutral drops out
of the circuit, as the individial loads become a series-parallel
voltage divider network. Each load receives 120V at its rated =power=.



--
-john
wide-open at throttle dot info


Assume you have a 200 amp 240 vac breaker with max load, you measure the
current on each leg and it is 200amps.This DOES NOT add up to 400 amps. The
current you measure on one leg is the SAME current you are measuring on the
other leg. Dont confuse same as meaning equal. Same means same as in you
read the curent on a conductor and slide the clamp on amp meter down the
wire a couple of inches and read the SAME current again.

If the currents in each side are not equal then the current in the low side
combined with the current in the neutral will be the SAME as the current in
the high side.. Kirchoff's law explains this a lot more easily using math
than English.