Bonding a Jeanneau Sun Odyssey 40

[Sean Herron]

Hello...

Here is something for aguement - a Jeanneau 40 recently from fresh water moorage - with no bonding of 7 bronze thruhulls - only a zinc on motor shaft...

Now in saltwater - would you advise bonding all said thruhulls and rudder post to a rider on motor shaft or flange or mounts - or is it really required assuming same are isolated...

What thoughts...

SH.

[alex fletcher]

I would recommend Review the total bonding system. I the boat is to operate in the salt. I have had quite a bit of Experience with Jeanneaus around the Sydney area. I use a Silver/zinc reference anode which is placed in the water 5 to 10 meter from the boat and left for a few day to react. The elect potential is then measured between the anode and the water. A reading is then taken between each conductive fitting that contacts the water and the water its self. All the Potentials should be the same if the potential at the fitting is higher than the ref anode the bonding is inadequate. Typically the cross sectional area of the bond wire must be increased generally due to high resistance in the bond wire. If all the readings are high on all thruhulls are Higher you may require a larger ground plate or in some cases the fitting of a suitable more efficient ground plate If all the readings are Greater the 20 percent lower than the ref. anode you may need a impressed current system fitted
hope it helps Alex
feel free to email me if you have any Questions Alex
I recommend this method as it looks at the local environmental anomalies of your mooring area like undersea power cables, large metal vessel close by and the like or if you are on a marina boat near by with poor shore power isolation