Originally Posted by mitiempo
You don't have to rely on marina for safety ground if the AC ground is connected to the DC negative per ABYC. That is the reason for its existence.
the reason for the AC to DC ground on the boat is in the event of a AC hot wire making contact inside the boat. to an engine
block, through hull
, anything metal in the boat. without the bond, NO ac breaker will trip, on shore or on boat. you now have a Live boat. putting AC into through hulls into the water
, and the engines etc are all live AC to the touch.
the only way to prevent this is to tie the grounds together. this will trip your AC breakers on the boat in the event of an AC wire shorting to metal on the boat.
though the boat still needs the shore ground in order for this to work. if you don't have a shore ground (and no transformer) the bond won't help you in this case. and you'd still have a live boat.