Good points, as usual, Tom.
Corona --besides greatly reducing the breakdown voltage-- can also generate
ozone, which can gradually break down some dielectric materials. When I
worked at Owens-Illinois in Perrysburg Ohio in the late 70's, they used
large insulated conductors to feed 12 kV 3 phase from the substations into
the building. After a few years, ozone finally deteriorated the rubber
insulation to the point that it failed catastrophically. A spectacular arc,
explosion, and a lot of damage and downtime was the result. (Bob Wacke
WA8SHH probably remembers that.) Those HV cables are now made differently,
some with a static drain on the outer cover.
73, Mike
www.w0btu.com
On Tue, Oct 1, 2013 at 11:10 AM, Tom W8JI <w8ji@w8ji.com> wrote:
> ... years of corona will slowly eat away the dielectric...
>
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Topband Reflector
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