I think there was a misunderstanding in Enios question regarding the batt-chargers connection. On the AC-side the charger connects to three cables: phase, neutral and earth. While phase and neutral "do" the electrical connection, earth is a safety feature: if there is any failure/broken cable in the device by which the housing might get "hot", the earth cable prevents an electrical shock. In europe the earth cable is green-yellow. Connecting the housing of the charger to the earth of the 220V system prevents electrical shock. Amel uses the green-yellow cable of the 220V AC circuit in the same way,
Amel uses another green-yellow cable system for a second purpose: connecting different metals to prevent electrolytic corrosion. All these cables unite finally in/to the strap in the bilge, which connects to the keel bolts.
These two green-yellow cable systems (earth and bonding) should never be mixed or connected.
From my experience hose-clamping the bonding cable to the seacocks, the manifold or other metals works fine, if everything is kept in good working order: dry. If the cables corrode: replace and keep dry. This will not work in the sump, unless you don´t use it ..., but that´s life.
Everything said refers to the european standard of 220V AC wiring, in the US the wiring is handled a bit different.
Walter (Noa, SM2K #436)