What is Shore Power?
220V shore electricity from the marina to the boat - a source of comfort, but also of corrosion and risk if it is installed incorrectly.
Shore power is the 220V mains supply taken from a marina pedestal to the boat via a dedicated cable and inlet. It powers the battery charger, sockets and, if fitted, the air conditioning. Through winter lay-up, the batteries usually depend on this supply.
But the other side of the coin must also be understood: the earth line in a shore connection electrically links boats in the marina, and that is the classic reason your anodes may waste away at an unexpected rate. The order of connection also matters.
Correct connection order
First switch off the breaker on the boat.
Connect the cable to the pedestal and the boat inlet (do not leave the cable floating in the water).
Then switch the breaker on.
When disconnecting, do it in reverse: switch off first, then unplug.
Overheating at the ends is the most common issue: oxidation on plug and socket surfaces creates resistance, resistance creates heat, and heat leads to melting. The ends should be checked once a season, and in winter a monthly 'touch check' of the terminals should be carried out to see whether they are running hot.
If the anodes are disappearing quickly, one of the likely suspects is the shore line; a galvanic isolator is standard protection. Do not compromise on cable quality, and if the pedestal breaker trips frequently it points to an insulation fault on the boat - moving to a breaker that does not trip is not a cure, only a delay.