Basic Shore power installation.

[193211]

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Hi,

I’m planning to upgrade the electrics on my 30yo Hunter. I bought the boat in August, last year. I’m happy tackling the 12v DC system but I would appreciate some input regarding earthing on the AC side of things.

Currently, the boat has a single 16A shore power socket. The cable runs from this socket, via a hard conduit to a double RCD plug. No consumer unit. I’m not happy with this setup.
I want to add a CU to safely provide power for two basic circuits. A Victron mains battery charger and a double socket with USBs.

The boat has an outboard engine in a well, rather than an inboard and the engine is not connected to the electrical system. It has the usual outboard anode.

In the absence of an inboard and it’s starting and charging circuits, what would this setup require in terms of earthing?

Thanks.
 

Refueler

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Risking alll .......

You admit boat has survived 30 odd yrs and has a minimal setup. The additions you want ? Just trying to understand why you want a Consumer Unit ... unless I have misread CU ??

I have a similar on my boat .... dual breaker that make sure NO power at all if anything happens. I have no earthing to water - to avoid strange problems in some not so clever marinas ...

I have EU and UK style sockets ... one set in main cabin - second in forecabin. My battery charger plugs into one of the main cabin sockets - I do think about wiring it in - but over the years never got round to it.

But what I do recc'd strongly :

Alastair Garrods book : Electrics Afloat

ISBN : 0-7136-6149-6
its a PBO sponsored publication and although been around for a few years - is a very good reference to explain all ...

All explained in plain and simple terms ....
 

VicS

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Hi,

I’m planning to upgrade the electrics on my 30yo Hunter. I bought the boat in August, last year. I’m happy tackling the 12v DC system but I would appreciate some input regarding earthing on the AC side of things.

Currently, the boat has a single 16A shore power socket. The cable runs from this socket, via a hard conduit to a double RCD plug. No consumer unit. I’m not happy with this setup.
I want to add a CU to safely provide power for two basic circuits. A Victron mains battery charger and a double socket with USBs.

The boat has an outboard engine in a well, rather than an inboard and the engine is not connected to the electrical system. It has the usual outboard anode.

In the absence of an inboard and it’s starting and charging circuits, what would this setup require in terms of earthing?

Thanks.
A garage consumer unit is a convenient way forward. Choose one with an rcd, a 16amp mcb and a 6 amp mcb for your requirements. There are a couple, by way of examples, on this page Garage Consumer Units | Garage Fuse Boxes | Screwfix.com

Current standards require a connection between the boats shorepower earth system and the water ( a small anode that is not part of any cathodic protection system will make a connection to the water in the case of a non metallic hull). If this connection is made and you leave the shorepower connected , even if not in use, for prolonged periods of time a galvanic isolator in the incoming supply may be necessary to protect the earthing anode.
 

PaulRainbow

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Hi,

I’m planning to upgrade the electrics on my 30yo Hunter. I bought the boat in August, last year. I’m happy tackling the 12v DC system but I would appreciate some input regarding earthing on the AC side of things.

Currently, the boat has a single 16A shore power socket. The cable runs from this socket, via a hard conduit to a double RCD plug. No consumer unit. I’m not happy with this setup.
I want to add a CU to safely provide power for two basic circuits. A Victron mains battery charger and a double socket with USBs.

The boat has an outboard engine in a well, rather than an inboard and the engine is not connected to the electrical system. It has the usual outboard anode.

In the absence of an inboard and it’s starting and charging circuits, what would this setup require in terms of earthing?

Thanks.

Mains Power on Board
 

KompetentKrew

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I want to add a CU to safely provide power for two basic circuits. A Victron mains battery charger and a double socket with USBs.
Not to answer your question, but surely the USB sockets should be on the 12v circuit so they'll continue to charge phones etc once the boat is underway?

The charger charges the battery, the USB sockets run off the battery.

This kind of faceplate may look attractive but using an inverter is an inefficient way to charge USB devices, and it risks accidentally flattening the battery if a higher wattage device is left plugged in when the boat leaves the dock.
 

[193211]

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There are already usb ports in the 12v system. On the main switching panel/ chart table, in the cockpit and incorporated into the lamps.

I really don’t want or need an inverter.

usb on the mains outlet socket is just redundancy.
 

Refueler

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There are already usb ports in the 12v system. On the main switching panel/ chart table, in the cockpit and incorporated into the lamps.

I really don’t want or need an inverter.

usb on the mains outlet socket is just redundancy.

Inverters are extremely inefficient regardless of the sales blurb .............. and of course you need to watch what format the output is ... clean or squared ..... etc.
 

Stemar

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Not to answer your question, but surely the USB sockets should be on the 12v circuit so they'll continue to charge phones etc once the boat is underway?
I have a few sockets similar to this scattered around the boat,
black-12v-24v-usb-port-socket-988-400x400.jpg


plus the reading lights above the bed have USB sockets, something like this
s-l640.jpg
 
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