Connecting shore hookup to battery - how does it wor

Adetheheat

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The electrics on the boat are battery powered dc. So when you connect to shore power which is ac how does that work? I didnt think you could connect an ac power supply to a dc battery?
 
You may or may not have a battery charger. My boat didn’t so 15 years ago I bought a temporary one from Halfords. Haven’t changed it yet as I rarely use it, even when spending a week or two on board in a marina. The 240V sockets and mains input to the boat (which I fitted) get used a lot.
 
The electrics on the boat are battery powered dc. So when you connect to shore power which is ac how does that work? I didnt think you could connect an ac power supply to a dc battery?
You can't, not directly. I have a 4 gang extension lead that I run from the shore to my boat and I plug any 240v appliances into that. If you wanted to charge up your 12v batteries then you could plug in a battery charger as well.
 
The 240v on my boat is connected to a small consumer unit from which some normal 13amp sockets are connected. Everything else runs if the battery which is kept topped up by a battery charger - one of the electronic ones.
 
I don’t know where to look for it, but a good place to start might be a very basic book or reference source on elementary physics, or at least electricity. I am far from being knowledgable about it myself but I do have a working knowledge of how circuits work, the relations between current, resistance, power etc, and how transformers work, though possibly 3-phase power was my pons asinorum. Although I did A-level physics a hundred years ago, actual circuits are usually beyond me, but the basic understanding still comes in useful.
 
The electrics on the boat are battery powered dc. So when you connect to shore power which is ac how does that work? I didnt think you could connect an ac power supply to a dc battery?
This question would indicate OP has just bought the boat or is just looking at boats. As said a battery charger is needed to convert the 240v AC to 12vdc for the batteries. It may be stowed away in a cupboard or in engine compartment. However it s common for the 240vAC cable to connect to a series of power outlets inside the boat. Bring your own toaster kettle etc. Also sometimes 240v AC to a heating element for hot water. It is possible that previous owner has taken a portable battery charger away with him. In that case a new battery charger is not very expensive depending on current capability. ol'will
 
The electrics on the boat are battery powered dc. So when you connect to shore power which is ac how does that work? I didnt think you could connect an ac power supply to a dc battery?

You run a typical car battery charger from the AC mains source - to charge your batterys.

You do not connect anything else to the AC mains source.

KISS
 
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