[C320-list] Lightning Storm Damage & Ion Dissipators

[Rick Sulewski]

Irv,

Here is an article at http://www.cgauxa.org/beacon/spring03BEACON.pdf  
about mast mounted ion dissipators that make that point that there is doubt
that any one approach is better than another when it comes to any attempt to
avoid lightening strikes.

At the Cleveland Boat Show where I purchased my 320 I researched lightening
protection systems and later ended up installing an ion dissipator (looks
like a 12 inch long 2,000 point copper bottle brush that has a diameter of
about 3 inches). I was told not to ground the ion dissipator as the cone of
protection from the rigging and the ion dissipater would provide protection
by preventing streamers from forming. At the time the same ion dissipators
were being installed on coast guard and military radio towers.

I initially walked away and decided to delay doing anything about protection
but considered investigating installation of a bonded system before I
launched.

Then some time later I bumped into guy who I recognized from my sailing area
and he told me that his multi-hull Stiletto was stuck by lightening two
summers ago and his hull was perforated at the waterline by the lightening
seeking to find a ground. When I asked him what he was now using for
protection since he already suffered his first lightening strike. He
indicated that he had installed the same large ion dissipator I ended up
purchasing. The same model was at one time an option on Island Packet
cruisers. This lightening strike survivor told me his insurance adjuster who
settled up on repairs told him that lightening protection bonding systems
may not avoid hull damage because the sharp turns that the heavy cables must
make to find a path to the grounding plate did not always work and actually
created a path for flash overs to other objects in the cabin. He learned
that the ion dissipaters were the way to avoid a streamer from forming
around his masthead.

That was some 14 years ago. While I have been in some spectacular
thunderstorms over the years while at anchor or tied up where I am the
highest point in the area, I have always said a prayer whenever thunder is
in the area and hoped that anyone who was struck by lightening while on the
boat and lived to talk about must have a special reason for giving me
insight into what work by giving me some peace of mind. 

The power of prayer assisted with some investment in technology gives me
some pause to fall asleep while the sparks fly overhead...and that is
priceless because I may never know if I am an stuck by lightening unless I
may also live to talk about it!

Rick
My-Ria 277



-----Original Message-----
From: c320-list-bounces at lists.catalina320.com
[mailto:c320-list-bounces at lists.catalina320.com] On Behalf Of Irving Grunes
Sent: Monday, June 16, 2008 11:33 PM
To: C320-List at catalina320.com
Subject: Re: [C320-list] Lightning Storm Damage

Guys,
When lightening strikes, it set up a huge expanding and contracting magnetic
field much like the field that is used in generators to create electricity.
There was the right hand rule,where the direction ogf the current causes the
field to rotate around the direction of the current.
This magnetic field is very large and when it expands and contracts,
anything metallic or electronic that is in the proximity of the field
expanding and contracting will get large voltages generated.
The electronics do not have to be on whatever the lightening strikes, but
only has to be in proximity of the large expanding and collapsing field to
get destroyed.
Surge protectors will only protect for the voltage surges that come over the
power lines.  Those devices in the field of the strike gets cooked.

So that even if someone has a lightening protector on top of the mast and a
chain going to ground, the path of the high amperage will set off the field
and cook whatever is close to it.  It will protect a person on the boat, but
its the field that does the damage.

Irv Grunes
#851















On Mon, Jun 16, 2008 at 9:04 PM, Stephen Cox <scox at timmin.com> wrote:

> There's only ways to reduce the possibility of a lightning strike and
> possibly the effects of a nearby one.  The energy involved will just
> totally
> swamp the normal "surge protectors".  If a boat nearby is struck the
> possibility of damage on boats around it are very high.
>
>
> Stephen Cox
> Tegwen C320 1141
>
> >
> > Quentin
> > Not 100% sure in your case, but downunder "surge protector"
> > are available and usually they are built into each individual
> > Marina power supply (one for each slip). Additionally, I have
> > a separate one (touch larger than the size on a computer
> > Mouse) for this purpose as well. We are on 240v supply and
> > our need is greater than yours at 110v.
> >
>
>