Subject: [AMPS] grounds
>
> In the US power distribution system, I understand that the neutral is
> connected
> to ground at the point of entry to the property's distribution board. Do the
> electricity company provide a ground wire in parallel with the neutral, or is
> the ground purely a local ground from a ground rod or similar?
Hi Peter,
I just wired my new home/shack/shop here in Texas. I will tell you how
it is here. My service starts out with a 30 kva transformer. It is ground
mounted,
and the service entry cables are all under ground. They drove a ground rod
at their transformer. The bare stranded wire is hooked to the ground rod. The
single phase 245 volts is fed to my service entrance box by two large conductors
that are wrapped in the ground wire. The customer provides another ground rod
at the service entrance panel to which the ground wire from the transformer box
is connected. The building is then wired with three conductor Romex cable, with
the neutral and ground conductors all tied to the ground bus in the service
entrance
panel. The "hot" conductors are fed through circuit breakers; dual breakers for
245 volts, and single units for 120 volt circuits. If sub panels are installed
down line
from the main entrance panel, they do not have a ground rod installed. Only the
rod at the main panel provides ground for the entire system. The neutral and
ground wires in the sub panel boxes are not bussed together as in the main
panel. They all run seperately to the main panel. I hope this answer is close to
what you were asking!
My ground rod at my service entrance panel is actually two rods tied together
with copper strap. A Polyphaser entrance panel is mounted next to the
electrical entrance panel that contains lightning protection devices
for all the antennas and phone lines. It is also bonded to the ground system
with heavy strap. A "whole house" surge protector is tied to the a.c. line
where it enters the entrance panel. So far, so good! (lots of fireworks from
Mother Nature here in E. TX!)
(((73)))
Phil, K5PC
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