> The tower ground is required to be bonded to the house's grounding
>electrode, but should not use the smaller #8 wire to get there. I would
take
>the 1/0 directly to the electrode.
Yeah, that's actually part of my system. The 1/0 wire from the panel goes to
one of the 12 tower electrodes (which are interconnected with 1/0 radials,
all Cadwelded), where it is Cadwelded to a length of 1/0 buried 4-feet deep
running 250' to a single-point station ground outside the house, where it is
Cadwelded to a 1/0 run connected to the house ground. Unfortunately, I had
to route this last run through the house to the service panel, which is on
the opposite side of the house. It's a very long run around the house to the
house ground electrode (over 125 feet) and I haven't gotten around to
digging the trench for that run.
As an aside, while poking around the service panel, I discovered something
interesting. A few years ago we did a major remodelling and had the electric
service, which used to hang in the air between the pole and the house,
buried in a conduit under the driveway. The four service wires, consisting
of the two phases, the service ground (neutral) and bare house ground, leave
the panel and run through a short length of conduit to a large conduit
junction box mounted on the ceiling. From there it appears that the wires
run through the side of the house to a pull box, down into the ground, run
about 50 feet through a large gray electrical conduit buried four feet deep,
up to a meter panel next to the pole, back down into the ground and back up
the side of the pole to the power transformer. There are at least three
ground rods around base of the pole and legs of the meter panel. I haven't
dug down to find out yet, but I think one is old and not connected to
anything. I believe that one of the two remaining rods is the telco ground
and the other is the house ground.
The upshot is that it looks to me like the bare house ground wire runs from
the service panel through a full 50 feet of conduit before it gets to the
electrode! I'm certain that there was an electrode right outside the panel
entrance before the remodelling. A bare wire still runs to the sill at that
point, but I don't think it's connected to anything outside (i.e., it looks
like it might have been cut off on the other side of the sill, but that
point is underneath a new exterior sill board so I can't be sure.) I'll have
to do a little digging around the pull box to be sure, but I don't think
there's an electrode there.
I don't know anything about the code or standard procedures, but I would
have thought a 50-foot run to the electrode was not the way to go. Seems to
me that an electrode right outside the house, as close to the panel as
possible, is the way to go. Even if there is an electrode connection there,
why put another connection through the conduit to an electrode at the base
of the pole? Should I have this installation looked over by a different
electrician than the one used by my contractor?
73, Dick, WC1M
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