Anode bonding

[icarusbop]

Hello:

I just spent two days re -wiring my anode bonding onboard as the old wiring was a mess.
I pulled out all the old stuff and replicated the connections that were already there, but with new better and well organised wiringn using 6mm yellow and green cable. ( the old wiring was 2mm and a mixture of red and black, just to add extra confusion. )

During this I noticed the anode was not bonded directly to the battery negative, but testing has shown it is connected to the battery negative by way of the engine block.
Should I put a direct bond from the battery negative to the anode?

Also, while I was at it, I noticed the sea cock for the sink was bonded to the anode, but not the sea cock for the sea water inlet. This raises the question, what is the current beat practice regarding sea cocks - bond them or not to bond them to the anode?

Thanks.

 

[GrahamM376]

Hello:

I just spent two days re -wiring my anode bonding onboard as the old wiring was a mess.
I pulled out all the old stuff and replicated the connections that were already there, but with new better and well organised wiringn using 6mm yellow and green cable. ( the old wiring was 2mm and a mixture of red and black, just to add extra confusion. )

During this I noticed the anode was not bonded directly to the battery negative, but testing has shown it is connected to the battery negative by way of the engine block.
Should I put a direct bond from the battery negative to the anode?

Also, while I was at it, I noticed the sea cock for the sink was bonded to the anode, but not the sea cock for the sea water inlet. This raises the question, what is the current beat practice regarding sea cocks - bond them or not to bond them to the anode?

Thanks.

Can't answer your question about negative direct to anode, ours is via engine block as yours is. Current thinking here seems to be not to bond seacocks as they're electrically isolated in grp with plastic hoses. I know thinking differs in the US but, according to a couple of surveyors here I've spoken to, bonding them could lead to problems if stray currents in marinas.

Sit back and wait for other theories

 

[VicS]

Not to bond skin fittings and seacocks you mean!

 

[VicS]

Hello:

I just spent two days re -wiring my anode bonding onboard as the old wiring was a mess.


During this I noticed the anode was not bonded directly to the battery negative, but testing has shown it is connected to the battery negative by way of the engine block.
Should I put a direct bond from the battery negative to the anode?

Also, while I was at it, I noticed the sea cock for the sink was bonded to the anode, but not the sea cock for the sea water inlet. This raises the question, what is the current beat practice regarding sea cocks - bond them or not to bond them to the anode?
Thanks.

Bond the anodes to what requires protection. To the block if that is the way connection is made to the stern gear, but remember flexible couplings must be bridged.

As such connection to the battery negative is not required but if the block is the negative return then you have made such a connection unless the DC system is isolated

Make sure the anode wiring is not also carrying any of the 12/24volt system current.

If shorepower is fitted the earth should be bonded to the DC negative as close to the battery as possible unless the Dc system is isolated. Galvanic isolator should also be fitted.

Skin fittings and seacocks should be of corrosion resistant material and should not be bonded to the anodes. See the MAIB recommendations in the report on the f.v. Random Harvest.

Btw MGDuff recommend 4mm cable.

 

[GrahamM376]

Not to bond skin fittings and seacocks you mean!

Yes, sorry, still half asleep!