Electrical Question / Advice

[Blue Moon PD]

So I have decided to go ahead with the 240v shore power on the boat that currently runs 12v through leisure batteries.

The list of what I think I need from a little reading and a few phone calls is as follows :

50m roll of 3183Y 2.5m Flexi Arctic Cable. ( is there a reason to use the blue cable over any other colour?)
IP65 Consumer Unit with a 63 Amp RCD , 16 Amp MCB and a 6 Amp MCB
Wall Plugs
I will use some of the 2.5m Arctic Flexi to make the shore line, with male and female connectors

So my questions or help I need are as follows :

Do I need a shore inlet or can I just use a male connector ?

I have seen some inlet covers for sale, is one of these required ?

Do I keep the lights I currently have as 12v ?

Is there some sort of switch or relay I need to switch between 12v and 240v, when going out to sea ? I don't think I need an inverter as trips to sea will only be day ones, always returning to port.

Can I run the lights at 12v whilst running the 240v for fridge etc whilst onshore at the same time ?

Thanks in advance .

 

[jfm]

Not being funny, but the nature of the questions means there are some important things you don't understand. Without wishing to dampen your enthusiasm or not praise your enthusiasm, you should read up on it or get help from an electrician

The 12v existing circuits need to be completely separate from 230v.

At its simplest, you could wire the 230v shore power through the RCB and MCBs to a couple of 13amp sockets in the boat, into which you could plug TV, toaster or any other typical appliances.

You could then fit a battery charger powered by 230v. This would have a 12-15 volt output connected to your batteries and would charge them. This charger would be the only "link" between the 12v and 230v systems on your boat

There is no switch or relay to "select" 12v and 230v when going out to sea. The 230v circuits would just be dead when you unplug the shore cable and go to sea. The (separate) 12v circuits would operate as normal

You don't need a shore inlet but it would be much better to fit a proper one with a lid on it to avoid corrosion etc. A caravan style one inside a weather proof locker might be ok

As you say it is better to forget an inverter for the time being. Just for a start you would need to isolate the shore inlet male terminals otherwise you could easily kill someone

 

[Seastoke]

you should use 10 amp breakers for your sockets, as the supply is only rated at 16 amp so if you use 16 amp on your sockets and 6 amp on your lighting the inlet could fail or catch fire at the extreme ,also the outlet on the jetty may be protected by a 16 amp breaker ,so if you have a fault it will trip the jetty breaker ,you will lose power and might not have accsess to switch back on.

 

[jimmy_the_builder]

is there a reason to use the blue cable over any other colour?

Blue is for 240v; the other common colour for arctic flex is yellow which is used for 110v.

 

[Blue Moon PD]

you should use 10 amp breakers for your sockets, as the supply is only rated at 16 amp so if you use 16 amp on your sockets and 6 amp on your lighting the inlet could fail or catch fire at the extreme ,also the outlet on the jetty may be protected by a 16 amp breaker ,so if you have a fault it will trip the jetty breaker ,you will lose power and might not have accsess to switch back on.

So replace the 16 Amp MCB for a 10 Amp for the ring main for the sockets ?

 

[Blue Moon PD]

Blue is for 240v; the other common colour for arctic flex is yellow which is used for 110v.

My understanding is 3183Y 2.5mm is all 16 Amp 240v rating !

 

[Blue Moon PD]

Not being funny, but the nature of the questions means there are some important things you don't understand. Without wishing to dampen your enthusiasm or not praise your enthusiasm, you should read up on it or get help from an electrician

The 12v existing circuits need to be completely separate from 230v.

At its simplest, you could wire the 230v shore power through the RCB and MCBs to a couple of 13amp sockets in the boat, into which you could plug TV, toaster or any other typical appliances.

You could then fit a battery charger powered by 230v. This would have a 12-15 volt output connected to your batteries and would charge them. This charger would be the only "link" between the 12v and 230v systems on your boat

There is no switch or relay to "select" 12v and 230v when going out to sea. The 230v circuits would just be dead when you unplug the shore cable and go to sea. The (separate) 12v circuits would operate as normal

You don't need a shore inlet but it would be much better to fit a proper one with a lid on it to avoid corrosion etc. A caravan style one inside a weather proof locker might be ok

As you say it is better to forget an inverter for the time being. Just for a start you would need to isolate the shore inlet male terminals otherwise you could easily kill someone

Someone on hear has mentioned replacing the 16 Amp MCB for a 10 Amp MCB for the sockets, would this work with 13 Amp sockets ?

I think I will do what you suggest regarding charging and powering the batteries through a battery charger.

When you say I need to isolate the shore inlet male terminals, what do you mean by this ? I certainly don't want to kill anyone!!

 

[Blue Moon PD]

One less thing I maybe overlooked , what about earthing ? I have read something about earth bonding cable to the hull ???

 

[jfm]

Yikes. Look, everyone is being kind and gentle in their responses, but actually everyone familiar with electrics is I bet horrified at the thought of a person asking these questions wiring up a boat @230v. There is no easy way to say this and I really don't wish to sound high handed, but anyone asking what you're asking needs to get an expert in and not DIY it

All that said, to answer your questions:
1. Yes is it perfectly fine to have a 13amp socket fed thru a 10amp MCB. It will trip at 10amps of course, but that's fine on a boat and will power a kettle for example
2. Battery charging isn't just my suggestion; it's the only way to do it really
3. I mean that if you were to fit an inverter, then unless you isolate the shore power connection at the back of your boat you will have make terminals live with 230v as soon as you turn the inverter on. You don't want seawater (a conductor) splashed on those or anyone to touch them
4. You earth to an earth plate under the hull. Many boat builders use the P bracket for this but it can also be a big copper plate

 

[jrudge]

Let go back to basics..... What are you trying to achieve?

Simplistically 240VAC will allow you to

- boil a kettle

- charge the batteries

- both of the above.

If you are simply after boiling the kettle etc in port then the "diagram" is shore power socket, breaker, power socket.

If you are looking for more ( or even just this) then given the questions you are asking I am with JFM - find a local marine electrician to do the work. If you buy all the bits and do the dog work like cutting socket outlets, running cables and so on the bill will be minimal and the work will be done correctly.

 

[landlockedpirate]

Its great that you are asking questions, but DIY, 240V and lots and lots of water is a no no.

Buy one of these, save yourself a bucket of money, a load of work and a possible visit to A&E.

http://www.gooutdoors.co.uk/mobile-mains-kit-p155317?gclid=CO-zy52zgb8CFagewwod6asAAA

Or get an electrician familiar with boats to do the installation for you.

 

[Blue Moon PD]

Everyone need not worry, I am not doing it myself just finding out what is possible and what is not, so I can get an idea of what I need to buy and cost up the project.

 

[David2452]

My understanding is 3183Y 2.5mm is all 16 Amp 240v rating !

It is actually 500vAC regardless of colour, but as Jimmy says the convention is to use yellow on site for 110vAC.

As far as the OP is concerned, leave it alone or get a qualified (and I mean qualified) person to do it, from your questions (and I mean no insult by this) your understanding is far below what is required to take on this job yourself, some basic advice has been given but far more is involved in doing it to a safe standard, I do all my installs to BS EN ISO 13297:2012 Small craft. Electrical systems. Alternating current installations, this is quite involved and specific.

 

[David2452]

Everyone need not worry, I am not doing it myself just finding out what is possible and what is not, so I can get an idea of what I need to buy and cost up the project.

Discuss what you want to achieve with a marine sparks or two and as for quotes, the materials required are cheap and a very small percentage of the cost in a simple install without inverters, combis and the like.