On Tuesday, November 19, 2013 8:50:23 PM UTC-5, nestork wrote:
Mark:



But, if what you're saying is true, then there is power flowing to

ground through the primary coil of every distribution transformer in the

USA and Canada 24 hours per day, 7 days per week, 365 days per year.



And, with a voltage of 7200 volts driving that current, it would seem to

me there would be a significant current flowing in the 40 or 50 foot

cable going down from the transformer to the ground.



Why don't those cables get warm to the touch?



All the power isn't flowing in those ground wires. You
typically have a neutral that is shared by multiple
transformers. Each transformer isn't connected to the
same phase, they are connected to phases in a distributed
fashion. That means that the current in the neutral is
only the unbalanced portion. If you had 3 transformers
for 3 groups of houses, each on a seperate primary phase,
with equal loads, the neutral current would sum to zero.

And then you have the neutral grounded periodically along
it's run, with a heavy, properly sized, ground wire,
capable of handling the current through it.








Is it entirely the impedance of the primary coil in the transformer?

There is a 24 VAC doorbell transformer in every house in the USA and

Canada. 120 Volt power is flowing through the primary coil of those

transformers 24/7/365 and yet no one seems to be concerned about that

power wastage. And, the only thing that makes sense here is that the

impedance of the primary coil is so high that the current flow to ground

is actually very small. Ditto for household transformers.









--

nestork