Installing shore power and battery charger

[Boeingdr]

The moody 29 I am purchasing has no shore power (and very few electrical nav gadgets) at present.
I want to fit the boat out with descent chart plotter DSC radio etc and fit shore power and battery charger.
The plotter and VHF should present little problem but Im not sure about the shore power.
All I want is a basic system to be able to charge the batteries without overcharging and at least one 230v 3 pin socket and perhaps an inverter connected to the batteries.
Is there a combined charger that can be connected direct to between shore conection and battery that includes all neccessary earthing RCB protection etc and a socket or 230v output and so ease installation?
I have 2 x 110 ah batteries I was thinking of 25 A charger or thereabouts.
As I said all I want is a simple but safe system.

 

[Jonny_H]

You want to look at the Dolphin All In One units from Merlin >> www.power-store.com

25A seems about right (10% of capacity is the general rule)

Jonny

 

[Malcb]

I've done the same on my boat. I bought a 'garage unit', which is a complete unit with RCD and two circuit breakers built into a box. For battery charging I bought a Sterling battery charger. The wiring was simple. The battery charger is wired into the 6 amp circuit breaker, and the 13 amp sockets on the boat wired into the 32 amp. Once I'd worked out where to site everything it took me half a day.

You can get the garage unit from Screwfix for around £37.

 

[asj1]

25 A will be more than adequate.

I installed shorepower and a permanent charger last winter. Relatively straightforward cabling. and so much better than the old trailing cable and halfords battery charger.
I used the following:
1) a Garage Consumer unit from Screwfix about £36, this has two cicuitbreakers for two seperate circuits
2) a Sterling 20A charger which I bought 2nd hand from this forum
3) a couplee of sockets from Scewfix and cable

I guess it was 5-6 hours work with all the problems of access etc normally encountered.

Regards


Andrew

 

[Boeingdr]

Thanks for the replies, would I need a galvanic isolator?

 

[Malcb]

[ QUOTE ]
Thanks for the replies, would I need a galvanic isolator?

[/ QUOTE ]

This is a personal opinion. If you earth the boats internal 240 volt electrics via a seacock or other metal fitting that goes to the outside of the boat, then yes fit a galvanic isolator.

If you are happy to depend on the suppliers earth connection, and not connect the boats earth to any metal skin fitting, then no you won't need one.

I haven't got one, as I haven't connected the earth to any skin fitting on the boat. I do however have a test plug which checks that the shorepower earth is a good one. It also checks polarity, so when I connect to a new shorepower point I check the circuits.

 

[DaveS]

Well, so far we're mostly singing off the same hymn sheet! Another vote for a "garage" consumer unit with a 30mA RCD as incoming isolator and, in my case, a 6A MCB for the battery charger (a Sterling 20A "smart" unit) and a 16A MCB for a couple of sockets wired as a spur. All wiring in flexible "arctic" cable. I regularly plug in a neon tester which confirms correct L N polarity and also the presence of earth via the shore connector. I also regularly test the RCD using the "Trip" button. On the rare occasions when I take shorepower from anywhere other than my home marina I always check these first.

Inverters are another kettle of fish, and it really depends on what you want one for. The integrated shorepower / inverter combined unit type are undoubtedly convenient, but rather dear. I have a simple (cheap) stand alone unit that is used maybe a couple of times a year to run a computer while at anchor or recharge the battery drill. If you want the "normal" mains sockets to also run from an inverter you have to install multi pole change-over switching and ensure there is no possibility of paralleling the inverter output with the shore power.

 

[Channel Ribs]

We are just finishing off a refit which is scarily similar to your plans, the bits which have impressed us no end are the Victron 3x 20A charger and the Standard Horizon Chartplotter (which handles NMEA and esp. AIS very well).

Deffinately go for RCD sockets or board, while you have easy access to the earths you may as well add a Galvanic Isolator.

Feel free to PM me for more info, don't want to say too much publicaly as it is a customer's boat.

 

[KellysEye]

There have been lots of good suggestions but take care regarding ambient temperature and location. Some battery chargers can go in the engine room, some can't.

 

[roly_voya]

Worth a troll though the archieves as ther have been several other post on 230v systems. My feeling is that if you just want a very simple system for battery charging plus 1 outlet then you could use a double RCD socket. Effectively this is an extension lead with an RCD on it but permenently mounted. If you want to go beyond and definatly if you fit an inverter then you should fit a propper system to the correct ISO standards. If going for an inverter you also need to chech that the alternator, batteries and core wiring are up to it as they can easily be drawing more current than a starter motor.

 

[gjgm]

Just looked into all this myself, and it can get pretty expensive- not hard to jump up to £500. Somewhat depends quite how much electrical safety you want. Garage units only break one side of the circuit-fine in a garage, arguably not so fine in a marine environment. A double breaker is alot more expensive. you also need to consider how you will use the charger.. leaving a normal charger connected can do serious damage to your batteries; fancy marine ones can get pretty expensive.
If its just for power when you are aboard, then the cheapest solution is one of the Sunncamp camping extension units. £60. Comes with 25m lead, rcd and double breaker, and sockets. Either wise, the Dolphin unit seems a pretty easy plug and play solution, but as someone mentioned, you do need to think about location.
Needless to say, having 240v running around your boat, sitting in water, has a rather high potential danger risk! Just be sure you know what you are doing...one advantage of the dolphin unit, perhaps.

 

[Boeingdr]

Thanks for lots of good advice here. The dolphin unit looks to be a sensible option for a safe yet straightforward system including batery charging.
On my last boat I simply fitted an extension cable with RCD, fine for accasional use but not really sitable with a smart charger.

 

[Phoenix of Hamble]

Yep... I fitted the Dolphin unit a couple of years ago to my last boat.... 3hrs work saw it fitted and working... from no shore power to having 240V sockets around the boat, and a stepped battery charger in 3hrs is pretty good IMHO and a vote for the dolphin kit....

FWIW, I did fit a Galvanic Isolator, it only took a few mins...

 

[DaveS]

[ QUOTE ]
Garage units only break one side of the circuit-fine in a garage, arguably not so fine in a marine environment. A double breaker is alot more expensive.

[/ QUOTE ]

Well, yes and no.

The RCD, which also acts as the incoming isolator, is a 2 pole device, i.e. both L and N are opened when it operates, either on sensing current imbalance >30mA (earth fault) or by manual operation. The MCBs are single pole, opening the L only when excess current is sensed.

Under what circumstances do you consider this arrangement might not be adequate?

 

[Kylora]

[ QUOTE ]
Under what circumstances do you consider this arrangement might not be adequate?

[/ QUOTE ]

If Phase/Neutral are reversed on the incoming supply.

Isolation by the 2 pole RCCD would be OK, but tripping the MCB only would leave the circuit live in relation to earth.

Ash

 

[DaveS]

Well yes, but...

you would have checked for correct polarity as a matter of course when you first connected up to shore power, wouldn't you? /forums/images/graemlins/grin.gif (See my previous post)

In the event that you did not check, and polarity was reversed, then a tripped MCB would indeed leave the circuit live, which is obviously undesirable, but if a live part then made a circuit to earth via something or somebody the RCD would operate.

 

[Chris_Robb]

Dave - checking polarity. you mention a neon tester, what is this, or can I have something set up permenantly to display polarity. If the polarity is wrong, what do you do? reverse your wiring - or is there something clever that does this for you?

 

[rogerthebodger]

[ QUOTE ]
I regularly plug in a neon tester which confirms correct L N polarity and also the presence of earth via the shore connector.

[/ QUOTE ]

Is this a neon indicator lamp commected between the Line and earth connectors so the if either the shore power earth is not connected or the L and N are reversed the neon will not be lit, only when Line , Neutral and earth are correct will the neon be lit

 

[DaveS]

(Also reply to Chris_Rob)

I use a tester which looks a bit like a standard 13A plug. There are various makes with different indications, but with each of them, plugging it into a 13A socket makes a combination of neons light up to confirm that mains voltage is present between L & N and L & E but not between N & E. Various wiring faults (reversed wires, disconnected L, N or E etc.) makes various other combinations light up, or none. An explanatory label clearly shows which is which. If reversed L & N polarity is revealed, then I suggest that the action to take next depends on the circumstances.

If you are connected to the supply in your "home" marina, then the problem clearly needs fixed permanently. The polarity of the marina socket needs to be checked first. This can be done with a test lamp or a voltmeter provided you (a) know what you are doing and are happy with poking things into live sockets, and (b) your test leads are in good condition and preferably fused. A blue 16A marina socket has the same polarity layout as a 13A socket: i.e. looking into the socket with the big tube (E) at "12 o'clock", the L tube is the one to the right i.e. "4 o'clock". A safer alternative is to buy or make up a short adaptor lead with a 16A plug on one end and a 13A socket on the other; plug the neon tester into the latter and plug the combination into the marina outlet. If the marina socket polarity is wrong, report it. If the marina socket polarity is correct but your internal sockets are wrong then you have a wiring error, and it's a matter of checking it through logically: shore power lead inlet socket, consumer unit, sockets until the reversal is found.

If you know that your "home" marina polarity is correct and your wiring is correct (as above) but your plug in tester shows reversed polarity when connected to shorepower in another marina, then their polarity is wrong. It should be reported but, given that you might arrive after staff have gone home, or they may not be able to fix it quickly, or maybe even care, it might be worth having the means on board to correct this. The simplest system is probably to make up a short "adaptor" cable with a 16A plug and socket which can be connected between the shorepower lead and the boat inlet. This adaptor would have L and N wires reverse connected at one end and should be prominantly labelled. I must say that I have not yet come across a marina with reverse polarity, so have yet to construct such a device, but my marina experience is quite limited and restricted to the UK. There are reports that e.g. in France polarity is often incorrect: a polarity reversing adaptor would then be useful. It is also possible to install a 2 pole changeover switch as part of the boat's wiring to reverse polarity as required, but I personally would think that the risk of inadvertant operation would outway the slight inconvenience of plugging in a polarity adaptor.

 

[rogerthebodger]

I am just in the process of designing a mains distribution panel for my new yacht to select (using a double pole 4 position selector switch) between off, inverter,generator and shore power.

The comment you made gave me a thought to incorporate an indicator to show incorrect connection on the shore connection.

I have found HellermannTyton do one but would like to incorporate it permantly.