Re: Split phase voltage fluctuations

[Ian Shef <invalid@xxxxxxxxxxxxx>]

Lewis Gardner <lgardner@xxxxxxxxxxxxxxxxxxxxxxxxxx> wrote in
news:45bd3129$1_1@xxxxxxxxxxxxxx:

<snip>
> I am not totally convinced that underground is the panacea that it is
> made out to be. Failures occur in both systems and underground takes
> much longer to fix. Of course underground failures don't usually happen
> all at once like a big wind or ice storm can cause. A few major
> earthquakes could change that...
I lived in Southern California for many years and experienced many
earthquakes, including the Northridge earthquake.

Aboveground lines fail in some earthquakes.  Aboveground substation
equipment falls over and causes failures.  Maybe there have been
underground failures due to earthquakes but I am not aware of any.

In the Northridge earthquake, underground natural gas pipes and water pipes
and sewer pipes broke or sprang leaks.  These pipes tend to be rigid and
brittle, breaking when flexed sufficiently.  Electrical conduit tends to be
more forgiving.  Even if it cracked, the wires inside would still be
usable.

In the Northridge earthquake, I lost water service because the concrete
meter vault sliced through the service line to my house.  I lost electrical
power because the substations were knocked out.  Once the substations were
repaired, power was restored.  The underground wires in my neighborhood
were untouched.  The underground transformer in a vault 50 feet from my
house was untouched.

Ice and wind take out overhead power lines directly and by bringing down
tree limbs on the power lines.  Ice and wind can't touch underground lines.

I will admit that the underground transformer was at a higher elevation
than my house, so that heavy rains would fill the vault until water ran
through the conduits that ran from the transformer and flooded the wall of
my house behind the meter panel.  Once the power company properly plugged
the conduit, I didn't have that problem anymore.

I will take underground reliability over above ground anytime.  The scenery
looks a lot better too.

--
Ian Shef     805/F6      *    These are my personal opinions
Raytheon Company         *    and not those of my employer.
PO Box 11337             *
Tucson, AZ 85734-1337    *