Consumer unit

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Sailing newbie selsey

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Hi I am looking to instal a consumer unit for my shore power ac, it currently comes into a very aged ciruit box with no RCD protection. I have a simple system on board which consists of a battery charger which charges two lead acid batteries one starter and one house. I currently have one power socket, which I plan to rewire to have 4 sockets around the boat.
i plan to use this consumer unit

British General Fortress 5-Module 2-Way Populated Garage Consumer Unit

i want to use the 6A MCB for the charger and replace the 32A MCB for a 16A for the socket circuit.

thoughts on my choice of consumer unit please.
 
That's very similar to what I have used except I only have one circuit. Be aware that having permanantly mounted 240V in the boat calls in a whole host of regulations about electrickery. A combination of Google, common sense, 'O' Level Physics and a healthy desire for self-preservation should see you OK though, but don't tell anyone what you are doing.
 
salar said:
That's very similar to what I have used except I only have one circuit. Be aware that having permanantly mounted 240V in the boat calls in a whole host of regulations about electrickery. A combination of Google, common sense, 'O' Level Physics and a healthy desire for self-preservation should see you OK though, but don't tell anyone what you are doing.
Click to expand...
No regulations at sea, surely? Do you mean BSS?
 
Sailing newbie selsey said:
Hi I am looking to instal a consumer unit for my shore power ac, it currently comes into a very aged ciruit box with no RCD protection. I have a simple system on board which consists of a battery charger which charges two lead acid batteries one starter and one house. I currently have one power socket, which I plan to rewire to have 4 sockets around the boat.
i plan to use this consumer unit

British General Fortress 5-Module 2-Way Populated Garage Consumer Unit

i want to use the 6A MCB for the charger and replace the 32A MCB for a 16A for the socket circuit.

thoughts on my choice of consumer unit please.
Click to expand...
I have just used similar, but you don't need 32A. Most marinas are 16A and you could never have demand on a small boat that ever meets that. I use the 6A for the battery charger and the 16A for a ring main with 2 sockets, one a double with USB ports. I have also fitted a galvanic isolator between the inlet and the consumer unit and earthed to a dedicated button anode in line with the latest standards, although this is not compulsory on retrofits. Makes sense however to do it though.
 
I fitted an 'all in one' unit with 3 sockets from Aldi/Lidl - you can get the same from camping shops. Obviously I fitted the correct 3 pin socket in the cockpit for the standard 13A supply from the marina bollard.
 
The main switch/rcd shout be type A or type B 30mA as there is a possibility of dc content from the electronics, the mcb's should be double pole (as well as the main switch) as you cannot be certain that the polarity at the socket you plug in to is always correct, you don't want a fault to trip the neutral leaving whatever it is supplying live but not working! Hager do some nice IP rated kit in plastic so it won't corrode, caravan consumer units are also available with double pole mcb's fitted.
 
Sailing newbie selsey said:
Hi I am looking to instal a consumer unit for my shore power ac, it currently comes into a very aged ciruit box with no RCD protection. I have a simple system on board which consists of a battery charger which charges two lead acid batteries one starter and one house. I currently have one power socket, which I plan to rewire to have 4 sockets around the boat.
i plan to use this consumer unit

British General Fortress 5-Module 2-Way Populated Garage Consumer Unit

i want to use the 6A MCB for the charger and replace the 32A MCB for a 16A for the socket circuit.

thoughts on my choice of consumer unit please.
Click to expand...

I have fitted more of these than i can remember, it's a good choice.

There are so many incorrect posts in this thread !!

So, the RCD is 2 pole, good.

The MCBs are single pole, along with the MCBs on just about every boat in the country, no problem with using them.

16a is correct for the sockets.

I have had several instances of chargers tripping 6a breakers when they start up, so i now fit 10a. Just make sure the cable is rated accordingly.

Post #6 gives good advice on fitting a galvanic isolator and making a secondary Earth connection, although that isn't compulsory (as Tranona says).
 
paul2884 said:
The main switch/rcd shout be type A or type B 30mA as there is a possibility of dc content from the electronics, the mcb's should be double pole (as well as the main switch) as you cannot be certain that the polarity at the socket you plug in to is always correct, you don't want a fault to trip the neutral leaving whatever it is supplying live but not working! Hager do some nice IP rated kit in plastic so it won't corrode, caravan consumer units are also available with double pole mcb's fitted.
Click to expand...

There are no requirements for double pole MCBs, almost every boat in the UK is fitted with single pole MCBs, that includes the big name EU imports.
 
PaulRainbow said:
I have fitted more of these than i can remember, it's a good choice.

There are so many incorrect posts in this thread !!

So, the RCD is 2 pole, good.

The MCBs are single pole, along with the MCBs on just about every boat in the country, no problem with using them.

16a is correct for the sockets.

I have had several instances of chargers tripping 6a breakers when they start up, so i now fit 10a. Just make sure the cable is rated accordingly.

Post #6 gives good advice on fitting a galvanic isolator and making a secondary Earth connection, although that isn't compulsory (as Tranona says).
Click to expand...
Thanks Paul your advice is much appreciated
 
All caravans have used double pole mcb's due to the risk of the supply socket having the L&N reversed, this has been in wiring regs for at least 10 years. The risk with a boat is similar but with worse

The domestic boards you have been looking at will have type B mcbs these are quick acting, if you are having trouble with things tripping (say a 4amp load tripping a 6amp mcb) use a type C mcb they will cope with the start up current better as they are slightly slower on inrush that is why you should use type c on florescent lighting.

16a mcb on the socket will mean you can use a quick boil kettle or 3Kw fan heater, you my trip the shore power mcb as that will be 16a as well to avoid this I fitted a small ammeter to the supply, it give me an idea of how much power I am using and confirms the voltage. We have a metal boat so have an insulation transformer so polarity isn't an issue but still use double pole mcbs

Hope this is give you some ideas I expect paulrainbow will be replying shortly as he likes to contradict anything i post!
 
There are other ways around the reverse polarity issue, though - without necessarily having to pack your CU with bulkier 2P MCBs. For instance, surely with a polarity indicator plus double pole RCDs, there is shock protection? Most of us would immediately stop using a reverse polarity supply anyway and sort it out (say, by using a specially wired and clearly marked adaptor as per the other thread).

I've got a all the bits for a CU ready to be installed on the boat with 1P MCBs and I'm not convinced yet. What exactly would 2P offer me? Over current protection on the neutral? My 2P RCD (I've also got a 2P RCDO before the CU, where the shore power enters) presumably provides earth leakage protection (if that's the correct term - I'm no sparky)?

As I said, SOP on our boat would be not to proceed drawing power from a reverse polarity hookup anyway.
 
dankilb said:
There are other ways around the reverse polarity issue, though - without necessarily having to pack your CU with bulkier 2P MCBs. For instance, surely with a polarity indicator plus double pole RCDs, there is shock protection? Most of us would immediately stop using a reverse polarity supply anyway and sort it out (say, by using a specially wired and clearly marked adaptor as per the other thread).

I've got a all the bits for a CU ready to be installed on the boat with 1P MCBs and I'm not convinced yet. What exactly would 2P offer me? Over current protection on the neutral? My 2P RCD (I've also got a 2P RCDO before the CU, where the shore power enters) presumably provides earth leakage protection (if that's the correct term - I'm no sparky)?

As I said, SOP on our boat would be not to proceed drawing power from a reverse polarity hookup anyway.
Click to expand...

What you have described is perfectly normal for a boat installation, double pole breakers are not required in current standards and unless you are foolish enough to ignore reverse polarity (i can see that's not the case) they offer you nothing.

You do need to fit a reverse polarity indicator or carry a plug in tester, i'd go for a permanent indicator.
 
The one the OP quoted is painted steel: not ideal for a cockpit locker which is a common place to fit it. I know plastic cased units are now not the normal spec for household use, but for a boat surely they are better.
 
That is the one that I have on my boat with similar electrical demands. Works fine.
Bob

QUOTE="Sailing newbie selsey, post: 8110545, member: 183849"]
Hi I am looking to instal a consumer unit for my shore power ac, it currently comes into a very aged ciruit box with no RCD protection. I have a simple system on board which consists of a battery charger which charges two lead acid batteries one starter and one house. I currently have one power socket, which I plan to rewire to have 4 sockets around the boat.
i plan to use this consumer unit

British General Fortress 5-Module 2-Way Populated Garage Consumer Unit

i want to use the 6A MCB for the charger and replace the 32A MCB for a 16A for the socket circuit.

thoughts on my choice of consumer unit please.
[/QUOTE]
 
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