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-   -   Spark stopper and lightning (http://www.sailnet.com/forums/electrical-systems/72048-spark-stopper-lightning.html)

scud 02-14-2011 04:27 AM

Spark stopper and lightning
 
Hello
I've always been a firm believer and supporter of NON-grounding insulated keel- stepped masts since it makes your boat more likely to get a direct lightning strike but after going through many thunderstorms with lightning bolts striking in the water everywere and very close to my boat, well ... I'm sort of tired of the feeling of squeezing my buttocks zip sealed and of the rattling of my crews' teeth. So I wonder... what about a spark-stopper connecting the keel to the mast?

In short the device can be described as a copper ball connected to the keel bolts with a thick wire or copper mesh. The copper ball is wrapped by a copper semi-sphere which is not touching it but it is maybe a mm away (practically a condenser with an all air-dielectric). The half-sphere is obviously connected to the mast. Supposedly a striking lighting would run down the mast, break the resistence of the air-dielectrik amd discharge thoughout the keel bolts minimizing the damage instead of discharging into water through the fiberglass hull.

I think the same could be achieved with a cluster of spark-plugs screwed in a steel plate while another steel plate holds them by the tips. Bottom plate is wired to the keelbolts while upper plate is wired to the mast.

The question is ... how many spark plugs and will it work????

Scud

sailingdog 02-14-2011 06:11 AM

I've said this before on lightning threads...

What does a million volt bolt of lightning do?

Anything it wants.

Where does a million volt bolt of lightning go?

Anywhere it wants.

scud 02-14-2011 06:20 AM

well ... SailingDog ... you do have a point and I ain't questioning it but I still think that the spark-stopper idea could be better than buttocks squeezing and hysterical panicking and whims.:confused: :confused: :confused: :confused:

maybe it's just psycological :rolleyes:

Scud

sailingdog 02-14-2011 06:49 AM

My point is that the spark stopper, regardless of how many spark plugs you use, is likely to be just as effective as buttocks clenching and panicking. If you think it will help, do it...but the real effect will only be psychological... it will be a placebo.

Quote:

Originally Posted by scud (Post 697860)
well ... SailingDog ... you do have a point and I ain't questioning it but I still think that the spark-stopper idea could be better than buttocks squeezing and hysterical panicking and whims.:confused: :confused: :confused: :confused:

maybe it's just psycological :rolleyes:

Scud


CapnBilll 02-14-2011 12:32 PM

Just ground the mast. I have used and experimented with various spark gap lightening arrestor setups for Radio transmitters. I've found them fairly ineffective. To ground the bulk of the strike without grounding your RF signal, use a 1/4 wave jumper. FOr anything else by the time you get a big enough gap to reduce odds of getting hit, you've also lost the effectivness, (remember that bolt just arc'ed through a couple of miles of air, the 1 inch, 10 inch, or 10 feet/meters of spark gap will have no effect). Neither will the difference of the top to the bottom of a 30 foot mast. The entire thickness of your boat even if it was made of a solid 15 foot thick block of fiberglass is not enough to stop it. Your best bet is give it the easiest path to ground you can that doesn't go through you or your hull. See lightening threads to find suggested grounding.

RichH 02-14-2011 01:46 PM

You might want to consult/view: http://www.marinelightning.com/EXCHANGEOct2007Final.pdf
and Marine Lightning Protection Inc. for some of the 'latest' thinking on marine lightning protection. On the surface, this is quite a different change/evolution from former 'in vogue' recommendations.

Also, the 'electronics' folks are also seemingly now advocating ultra-high frequency 'chokes' on all important 'electronic' equipment to prevent/retard the 'Radio Frequency' RF aspects of a lightning strike.

Been hit twice .... dont want to get hit again. One was an RF event that fried every electronic device on board (and that was not inside the oven), the other was an amperage event that blew a big chunk out of my keel --- so I kind of think from those two experiences that keeping 'lightning totally outside of a boat' and on the 'surface of the boat' is kind of 'important'.

hellosailor 02-14-2011 01:52 PM

"My point is that the spark stopper, regardless of how many spark plugs you use, is likely to be just as effective as buttocks clenching and panicking."
Eh, well...Folks like Polyphaser have been making and selling lightning arrestors to the broadcast industry for years. And those folks *usually* keep on transmitting, despite lightning and thousand foot tall antenna towers, 24x7.

They have white papers available online. they won't stop everything every time. But they sure can improve your odds when compared to just doing nothing.

sailingdog 02-14-2011 02:49 PM

Quote:

Originally Posted by hellosailor (Post 698014)
"My point is that the spark stopper, regardless of how many spark plugs you use, is likely to be just as effective as buttocks clenching and panicking."
Eh, well...Folks like Polyphaser have been making and selling lightning arrestors to the broadcast industry for years. And those folks *usually* keep on transmitting, despite lightning and thousand foot tall antenna towers, 24x7.

They have white papers available online. they won't stop everything every time. But they sure can improve your odds when compared to just doing nothing.

LOL, but I doubt those are made from spark plugs. :D


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