Keel Earthing

beneteau_305_553

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Is it normal to have an electrical connection from the mast to the keel?

New Beneteaus do not seem to be connected. Is this to eliminate electrolysis corrosion of the keel? I thought they should be connected to provide earthing to prevent lightning damage. My old Beneteau had a connection but also a rusty keel.

The 12 v system is earthed via the engine to the water but not connected to the mast or the keel.
 
[ QUOTE ]
electrolysis corrosion of the keel?

[/ QUOTE ] Nothing to do with electrolysis unless you keep mast and keel both in the water for long periods. Then the mast would act as a sacrificial anode, wasting away as it protects the keel!
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For lightning protection the wire should be quite substantial. Something the size of starter wiring would be good although you might never have enough wire to carry a lightning strike the larger wire might divert current from going via engine and shaft to the sea. olewill
 
On my Finngulf I have substantial cables from the mast foot and both chainplates to one of the keel bolts. I don't know if its normal but I'd say its a good idea.
Dave
 
If it were me I would disconnect the earthing to the chain plates. The problem is that SS rigging wire has enough conductivity to try to carry large currents but enough resistance to get really hot with just a 100 amps or so. That will destroy the rigging wire or at least its ability to do the job by softening it.
The Al mast has very good conductivity (low resistance and could conduct a lot of current without overheating. (damage) olewill
 
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