correct installation of a new charger


Good afternoon everybody.

 I replaced the old battery charger TECSUP with a more powerful Sterling. This has a screw on the casing wich I believe will serve to be connected to the earth of the boat.  What should I do? Put a wire to be connected at any point of the bonding system, it is correct? 

And what problems there might be unless I connect it?

Thanks for your help. Enio


Dear group,
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)

Alan Leslie

Yes all good..>EXCEPT..there is a connection between the AC ground and the bonding circuit, in my boat at least and that is due to the 220VAC saltwater pump for the air conditioning...there the AC ground is connected to the "saltwater" ground or bonding.....
Elyse SM437


Hi Alan,
yes, I know about the exeption with the Calpeda pump. Amel decided to add it to the bonding system and as they were doing it for a long time there seemed to be no negative response from the technicians - so we stick to it. But we keep a close eye on the electrical systems and restrain ourselves in adding equipment. There is no corrosion on any parts or the c-drive.

Walter (Noa, SM2K #437-1)