galvanic isolator

[dogdoc]

I decided early on to eliminate all ac on my boat except the onboard battery charger. At the present time there is no ac going to the bulkhead or cabin. I moved the twist lock ac input from the starboard side to the port side and installed a new galvanic isolator in the battery compartment. I ran the green ground from the boat side of the ac input to the galvanic isolator and then on to the ac ground terminal on the battery charger, the hot and neutral from the boat side ac input run directly to the battery charger. The only communication from the ac side to the dc side is the chassis bonding wire of the charger which runs to the negative bus in the battery compartment. I thought about running the green from the galvanic isolator to the negative bus but that just does not seem right to me, wondering what others think, thanks

 

[seasick]

If your boat has ground bonding cables, the green wire from the isolator should connect to the common point hat was originally connect to shore ground. It probably is right now since all you seem to have done is splice the isolator ground into the original feed. The point where the isolator green wire that is towards the boat connects to that common ground point is where the charger ground should go. Often that was the AC ground bus bar but I don't know what you had and removed. Don't confuse AC neutral, DC ground and AC ground (Earth) they are not the same electrically
It is not advisable to connect any 'grounds' directly to the battery for two reasons: First of all the battery terminals are +12v and negative battery. That is not earth ground. Connected earth grounds to multiple points can created ground currents, very small typically' but potentially ( pun intended) damaging.

So as long as the remaining green grounds, the isolator ground (boat side) and charger ground all connect to a common point, you should be OK.