On 1/26/2011 12:29 PM, KD7JYK DM09 wrote:
> I have taken photos of our electrical "grounds".
You need to study the fundamental principles of AC power distribution. A
GROUND conductor does NOT carry load current -- it's sole function is
SAFETY. The current carrying conductors are the Phase and Neutral
conductors. A 240V single phase system has two Phase conductors and a
Neutral conductor, fed from a center tapped transformer. The two Phase
conductors are connected to the two ends of the transformer, and the
neutral is connected to the center tap. There is NO ground conductor
between the power company and your home. Rather, the Neutral conductor
is grounded FOR LIGHTNING SAFETY both at the transformer and at the
point where it enters the building. A separate Equipment Ground
conductor (the Green wire) is carried with the phase and neutral
conductors to every outlet, and to every piece of equipment wired
directly into the power system. The purpose of that Green wire is
SAFETY. It's function is to cause a fuse (or breaker) to blow if
something goes wrong.
The EARTH is a lousy conductor, and should NEVER carry current in a
power system. A connection to earth is almost never part of a solution
to an RF or noise problem.
There is a tutorial discussion of power systems on my website.
73, Jim Brown K9YC
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