240 volt system into yacht

I revived it after doing a search. A friend is buying a Westerly who's mains power system is just a round pin socket connected to a couple of 13amp switched sockets. Naturally I am concerned and have told him to install a propoer system. I thought this thread might point the way but, although there is some in-depth discussion, it doesn't seem to reach a conclusion. A garage system and a couple of ring mains seems possible but these don't have double pole breakers so not really compliant. Some of the proprietary 'boat' systems don't have DP breakers either and is galvanic isolation really necessary?
 
ghostlymoron said:
I revived it after doing a search. A friend is buying a Westerly who's mains power system is just a round pin socket connected to a couple of 13amp switched sockets. Naturally I am concerned and have told him to install a propoer system. I thought this thread might point the way but, although there is some in-depth discussion, it doesn't seem to reach a conclusion. A garage system and a couple of ring mains seems possible but these don't have double pole breakers so not really compliant. Some of the proprietary 'boat' systems don't have DP breakers either and is galvanic isolation really necessary?
Click to expand...

There was another thread that pretty much came to a conclusion (albeit with forum members agreeing to disagree). Basically your best bet is to buy a garage unit and add the appropriate parts. How many parts depends on two things, one is how bothered you are by regulations (not safety, regulations). The other is how thorough you want to be. Have a read of the regs and choose which parts are necessary for your safety and ensure they are in the solution. Then add in the remaining things based on your personal thoughts on regs and thoroughness.

I wasn't bothered at all by the regs, but do have a safe installation. My installation, however, doesn't have a main isolator switch because the boat is small enough that it would be excessive. To isolate I can simply remove the shore lead. If my boat was larger I would have fitted one, and if I ever stood a chance of going somewhere not Britain I'd have fitted at least a polarity indicator if not something to prevent the system being used with back to front power.
 
Lustyd, what did you add to your garage unit? Do you have double pole mcbs? Doesn't the DP ELCB act as an isolator? I don't think my mate is bothered about Galvanic isolation because a)he's no idea what its for and b)he's not going to spend much time in a marina.
 
ghostlymoron said:
Lustyd, what did you add to your garage unit? Do you have double pole mcbs? Doesn't the DP ELCB act as an isolator? I don't think my mate is bothered about Galvanic isolation because a)he's no idea what its for and b)he's not going to spend much time in a marina.
Click to expand...

The questions you need to be asking are more along the lines of whether the boat has onboard generating capabilities, what is connected to the power system, and finally what are you protecting from. The answers to these and other questions like them will give you the answers to other questions. Generating power on board changes how you treat the earth, and connecting things up changes how you view galvanic isolators. I'm not good enough at this stuff to answer the question unfortunately, I just know what I needed/wanted in my boat. There are plenty on here who can explain everything but your best bet is a new thread, fully describing the yacht and the desired capability or likely expansions. My 20 footer will never have a generator for instance so I ruled that out in the design.

It's not a popular answer, and it's certainly not to regs, but I actually added nothing to my unit. The installation is detailed on my blog, and the parts list are on a thread I started on here a couple of years ago. Most people publicly disagree with what I did because my installation lacks a couple of features from the regs. As I said I have no isolator switch since I can unplug. I have no "proper" overcurrent protection, but do have trip switches. The difference is subtle - one of them will stop the supply if your device shorts or if you get electrocuted etc. and cause current to leak from the system. The other will cut out if you draw too much power. My boat is 20' and has two sockets, it would be incredibly hard to accidentally overload the cabling which is all overrated apart from the shore connection outside which is a standard cable. I'd probably have to plug a 4 way power strip into each of my sockets and run nothing but fan heaters to overload, and even then the heat would make it obvious!

That said, if the boat was just a few feet longer, more sockets and more space would make the difference to accidents being not only possible but probable. A few phones on charge, a kettle, a heater, charger and fridge and you might easily overload a shore cable and so the choices would be different.

I hope this had helped rather than hindered. If you say whether you're looking for a full regulation spec system or not that would help a lot. On the other end of the scale you can get a power lead with a box on the end from caravan shops. They aren't pretty but they are safer than a wire and socket alone, and cheaper than a full install.
 
I've just added the single socket camping one from Towsure, but bypassed the single socket and added a double socket where I wanted it. It's single pole, but has a warning light for reverse polarity.
 
Ru88ell said:
I've just added the single socket camping one from Towsure, but bypassed the single socket and added a double socket where I wanted it. It's single pole, but has a warning light for reverse polarity.
Click to expand...

Don't you have to have the cable going through the companionway/window with those?
 
I tried to get a Sparky to wire my yacht for 240V but no-one was interested.
I have a 1500W Inverter. and plugged in a power board with 4 outlets (the power board has an RCD device). I then plugged in 4 extension cords and took one to a power point in the shower/toilet, one to the galley, one to the microwave and one for general use eg bread-maker. Everything works fine.

As luck would have it a Sparky came by socially and I put it on him to check out my installation. He said there was nothing wrong with it but he was bewildered as to why I would use extension cords when it would have been much cheaper to use normal electrical wiring.

If there is an expert out there that can point out that where I have gone wrong please let me know.
 
VicS said:
....I would advise you to seek professional advice.
Click to expand...

So much advice on here, but this is the best. EDIT: But do make sure it is a "marine" sparky who really knows what they are talking about.

If you can find a "friendly professional" that you can work with and do most of the cable laying installation yourself - that will save you a lot of money.

Also checkout this postings about the increasing number of people being killed in the water by faulty AC installations on boats. It was previously thought many of these deaths were due to drowning. It could be you or your family that gets killed.

http://ecmweb.com/content/case-hot-marina
 
Last edited:
coopec said:
I tried to get a Sparky to wire my yacht for 240V but no-one was interested.
I have a 1500W Inverter. and plugged in a power board with 4 outlets (the power board has an RCD device). I then plugged in 4 extension cords and took one to a power point in the shower/toilet, one to the galley, one to the microwave and one for general use eg bread-maker. Everything works fine.

As luck would have it a Sparky came by socially and I put it on him to check out my installation. He said there was nothing wrong with it but he was bewildered as to why I would use extension cords when it would have been much cheaper to use normal electrical wiring.

If there is an expert out there that can point out that where I have gone wrong please let me know.
Click to expand...

I can't tell if this is a joke or not :confused:

Just in case it's not, "normal" electrical wires are solid core so tend to snap when used on boat installations leading to potential fires.
 
sailinglegend420 said:
So much advice on here, but this is the best. EDIT: But do make sure it is a "marine" sparky who really knows what they are talking about.

If you can find a "friendly professional" that you can work with and do most of the cable laying installation yourself - that will save you a lot of money.

Also checkout this postings about the increasing number of people being killed in the water by faulty AC installations on boats. It was previously thought many of these deaths were due to drowning. It could be you or your family that gets killed.

http://ecmweb.com/content/case-hot-marina
Click to expand...


The installations may not have necessarily been faulty. Many boats earth to the water due to onboard generation capabilities. Marinas often ground to water too which can make a loop. In theory the RCD should cut the power but there are many reasons why it may not, for instance water connecting the incoming power to ground before the RCD. This is one of the reasons you're not allowed to swim in marinas and why only "proper" divers are allowed to dive there.
 
lustyd said:
The installations may not have necessarily been faulty......
Click to expand...
Please read the link before posting any more bad advice like your previous posting:

lustyd said:
...I wasn't bothered at all by the regs, but do have a safe installation. My installation, however, doesn't have a main isolator switch because the boat is small enough that it would be excessive....
Click to expand...
Even on a small boat you need to follow the regs!!!!!

I'll include my signature on this post.
 
Nigel

The power point in the shower/toilet is installed high up inside a locker so it can't get wet. Likewise the power point in the galley is high up near the deck. The electrician said both were OK! Thanks anyway
 
lustyd

The electrician does lots of work on the fishing fleet so I'm sure he wouldn't be suggesting single core!!!
 
Having read some of the posts on these threads I am rapidly coming to the conclusion I must be Very careful before taking advice!!!
 
You must log in or register to reply here.

Share this page

Top