4316RE: [campernicholson] Lightning Protection
- Jul 2, 2008
My boat, Trutz #225 has lightning protection. It was originally built for a German owner who had plans (and all the charts) for a trip down the West coast of Africa . He was clearly expecting to encounter some thunderstorms.
It sounds like a similar installation to your own. The mast is grounded via a cable attached to the port side of the mast just above the mast heel. This wire goes to a sintered metal grounding plate which is bolted through the hull. This sits on the port side of the hull about a foot below the waterline. We also have another pair of these plates stbd aft but I think that they are to do with the disused SSB installation.
I have done a bit of research on this subject and all I can say is that the arrangement that we have on board is probably not really up to the job. This isn’t a problem in the UK where thunderstorms are not quite so regular. However, for use in sub tropical or tropical areas you might want to talk to a specialist. The problem seems to be that a really big strike might not be properly dissipated in time leaving you with a lot of high voltage flying around in the rigging and bouncing off of important things like instruments and crew. Not a nice prospect. Those sintered metal plates are very good at spreading the load though so maybe adding another one or two of those and upgrading the cable might give some peace of mind.
There are some very specialized companies out there who will no doubt charge you a lot of money to upgrade your protection but, at the end of the day, it seems that keeping your fingers crossed is the best policy. You probably already know this but apparently if you can disconnect all your valuable electronics and put them in the oven during a storm they will be protected from the strike.
Hope this helps in some way.
All the best
Colin & Jo
From: email@example.com [mailto: firstname.lastname@example.org ] On Behalf Of Albert G. Boyce
Sent: 02 July 2008 03:06
Subject: [campernicholson] Lightning Protection
I am wondering what other Nicholson 35 owners have done for lightning
protection. I have developed a keen interest in lighting protection
after getting caught out on the Chesapeake in a thunderstorm last week
and getting a mild electric shock at the helm while steering the boat.
Quite a wake up call. I have hull number 132 and there is a small
sintered bronze plate on the outside of the hull that is connected by #8
wire to the mast.
None of the shrouds, stays, lifelines, stanchions, or any other metal
objects are grounded or otherwise connected to this plate
I look forward to hearing what lightnting protection arrangements others
have in place on their boats.
Discovery CN35 #132
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