Lightning Protection

JamesG161

SBO Weather and Forecasting Forum Jim & John
Feb 14, 2014
7,717
Hunter 430 Waveland, MS
like the idea of chains from the boat to the ground. Are they connected to ground rods into the ground or just laying on the concrete or gravel?
One is a pile of anchor chain, pulled out of my Locker for repair. The others are connected to the Jack stands, dug into the ground and cross supported with their chains.

Easily verified on my boat with a DVM.
Jim...
 
Oct 26, 2010
2,028
Hunter 40.5 Beaufort, SC
I believe ABYC recommends 6 gauge minimum (4 gauge is better) ground wire from mast base to keel bolt and 8 gauge minimum from chainplates, etc. to keel bolt. Of course connection to the keel bolt is only for external mounted keels, not encapsulated.
I was going from memory. I doubt very much mine is 6 guage. I'll look with I get to the boat but if its as @JamesG161 indicated its to maintain the mast as the same potential as the water, then gauge isn't very important as very very little current is actually carried by this wire to simply maintain the ground potential.
 
Oct 26, 2010
2,028
Hunter 40.5 Beaufort, SC
@JamesG161 not sure I understand. Where are they connected on the boat to something connected to the mast or ground system on the boat? The stands set up against fiberglass, which is not a very good conductor, if at all. The chain pulled out of the anchor locker, unless attached to something metal on the boat would most likey be insultated from the boat by the fiberglass anchor locker.
 

JamesG161

SBO Weather and Forecasting Forum Jim & John
Feb 14, 2014
7,717
Hunter 430 Waveland, MS
The chain pulled out of the anchor locker
Yes! To the Windless which is connected to the Boat Ground Buss
Simple to confirm use a DVM. Tough to explain here , but think of how a boat on the Hard can verify it with someone aboard and some on the ground testing for 0 ohms resistance. ;)

Jim...

PS: I believe you still have my home phone number in our past PM.
 
Oct 6, 2007
1,107
Hunter H30 1982 Chicago IL
I was going from memory. I doubt very much mine is 6 guage. I'll look with I get to the boat but if its as @JamesG161 indicated its to maintain the mast as the same potential as the water, then gauge isn't very important as very very little current is actually carried by this wire to simply maintain the ground potential.
Mine was 8 gauge and I upgraded to 6 gauge when I re-wired the mast last year. 4 gauge was too large to fit.