240 volt system into yacht

lustyd said:
Here we go an RCBO which will replace the RCD in the consumer units and make it comply with ISO :)

Then you just need a label maker to comply with the other requirements...
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That RCBO I am sure fits the bill!

would make me happy.

Should make testmonkey happy too.
 
My confusion is getting confused.

Its been a few years but my understanding is that garage consumer units are an extension from a main consumer unit which contains an 'off means off' double pole isolator switch which these days is often lockable. If used as a a stand alone unit the RCD becomes the only switch and does not really comply with normal wiring regulations. Is such an arrangement now deemed as acceptable.

Actually the the Towsure /Aldi units do seem to have a double pole isolator and a double pole RCBO and a polarity indicator although you wouldn't guess so from the available information. A brief glance at the leaflet suggests that they wont actually work if the supply polarity is reversed.

Anyone care to unconfuse me?
 
On my boat off can be achieved by removal of the shore cable. This is not a house so has different requirements.
 
VicS said:
Yes we saw it first time around but we are taking about fixed installations. In particular about the suitability of various consumer units and the application of ISO13297.

The Kampa units from Towsure do however appear to satisfy the requirement for a DPMCB and an RCD ( hopefully that is DP )
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My point was that these can be the basis of a permanent solution, with a few cheap tweaks;

I.e. Buy the one with 3 power sockets and cut the long orange cable off and put a plug on the end and you have a shorepower cable. You could either remove the 3 power sockets and locate these round the boat, or keep it in one peice and use a 13amp plug to run cable from here to the relevant sockets. (After all you will more than likely need at least one or two power sockets in this location for a battery charger etc).

Open up the beige box and find somewhere to fix the box on board, and wire through to a socket on deck and you have the boat side started, yes it needs some simple alterations, like a galvanic isolator, and grounding to the battery but for £50 its a very cheap way of getting most of the basic components you need. And as you say its meets the main discussion need of a double pole isolator, and also for the reverse polarity check.
 
Daydreamer said:
My confusion is getting confused.

Its been a few years but my understanding is that garage consumer units are an extension from a main consumer unit which contains an 'off means off' double pole isolator switch which these days is often lockable. If used as a a stand alone unit the RCD becomes the only switch and does not really comply with normal wiring regulations. Is such an arrangement now deemed as acceptable.

Actually the the Towsure /Aldi units do seem to have a double pole isolator and a double pole RCBO and a polarity indicator although you wouldn't guess so from the available information. A brief glance at the leaflet suggests that they wont actually work if the supply polarity is reversed.

Anyone care to unconfuse me?
Click to expand...


Read ISO13297.

My understanding is that section 7.2 requires a DP Circuit breaker in the incoming supply. An RCD does not satisfy that requirement... it is a not an over-current protection device.
Presumably a consumer unit fitted with a DP MCB, as well as an RCD, or with an RCBO will satisfy the requirement provided it is within 0.5m of the inlet connection or if the wiring is protected as specified in 7.2.2.

The garage units, and the consumer units offered by Merlin Power-store, both it seems will require a DP circuit breaker in the wiring between them and the inlet connection.

Removing the shorepower cable as Lustyd suggests does not satisfy the requirement... It is not over-current protection!
 
SimonA said:
I'd like to fit 240v on my boat, which is a river boat on freshwater.

Do I need to fit a Galvanic Isolator and if so how does this connect up?
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It fits in the incoming earth connection.

The diagram HERE shows how one (ZinGuard) is fitted

It is only needed if the shorepower earth is bonded to the vessel's DC negative, and anodes etc and only if the shorepower is left plugged in for prolonged periods.

I'd dont know how important fitting a GI will be in freshwater. Next to vital in salt water if the shorepower is plugged in all the time.
I'd feel inclined not to fit one but monitor the situation carefully and fit one if there appears to be a need.
 
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VicS said:
Removing the shorepower cable as Lustyd suggests does not satisfy the requirement... It is not over-current protection!
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I meant instead of an isolator switch - on land these are to switch the supply off to the building. On a boat, as we agreed above you need the RCBO which protects but to isolate the supply you can just unplug so there's no need for a switch as well, especially given that these will be 2 way which means that we're now looking at an 8 way box at least to house it all which is not practical on smaller boats. On something over 30' maybe you would fit an extra isolator switch but lets not get carried away following regs for the sake of it - that's what lead to the sea cock issues after all!
 
VicS said:
Read ISO13297.

My understanding is that section 7.2 requires a DP Circuit breaker in the incoming supply. An RCD does not satisfy that requirement... it is a not an over-current protection device.
Presumably a consumer unit fitted with a DP MCB, as well as an RCD, or with an RCBO will satisfy the requirement provided it is within 0.5m of the inlet connection or if the wiring is protected as specified in 7.2.2.

The garage units, and the consumer units offered by Merlin Power-store, both it seems will require a DP circuit breaker in the wiring between them and the inlet connection.

Removing the shorepower cable as Lustyd suggests does not satisfy the requirement... It is not over-current protection!
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How very odd. I suppose it may depend on ISO's definition of a circuit breaker but there seems to be no explicit requirement for double pole isolation.
Pull the plug out it has to be!
 
Daydreamer said:
How very odd. I suppose it may depend on ISO's definition of a circuit breaker but there seems to be no explicit requirement for double pole isolation.
Pull the plug out it has to be!
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Read the ISO and I think you will find you are wrong

3.19 is the definition of a DP circuit breaker !

7.2 sets out the requirements for a DP CB in the main supply circuit.

Pull out the plug DOES NOT satisfy the requirement for overcurrent protection.
 
VicS said:
Read the ISO and I think you will find you are wrong

3.19 is the definition of a DP circuit breaker !

7.2 sets out the requirements for a DP CB in the main supply circuit.

Pull out the plug DOES NOT satisfy the requirement for overcurrent protection.
Click to expand...

Actually I'm not particularly concerned about overcurrent protection this is obviously achieved by MCBs or that function of an RCBO. My rather small concern is about standardised procedures for safe working. Not just for the guy who fitted the system but for anybody who may eventually work on it and isolation procedures are fundamental here. If the mechanical switch on an RCD is deemed as satisfactory (and I think it may be) then fine as long as we all know. If pulling out the plug is the standard then OK but a quick scan of the ISO document does not give any obvious guidance.

Frankly its hardly worth the mention but since both the Aldi device and the Merlin setup both seem to have isolators built in it did seem to raise an interesting question.
 
Surely anyone smart enough to use an isolator (switch) is capable of working out that pulling the plug also cuts the power? If not then frankly I'd say let Darwin sort them out.
 
lustyd said:
Surely anyone smart enough to use an isolator (switch) is capable of working out that pulling the plug also cuts the power? If not then frankly I'd say let Darwin sort them out.
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Pulling the plug will cut the power. If you pull it

BUT the requirement is for a double pole circuit breaker on the main supply . That is one which automatically cuts the power on over-current.

Surely anyone can see that pulling the plug is not automatic over-current protection! If not then perhaps your Mr Darwin will explain it to them.

The Kampa units at least appear to have an MCBO rather than just an RCD so perhaps a shorepower installation based on them would comply in the above respect but they may fall short of section 7.3.1, which requires that
"the live conductor of each branch-circuit in a polarized system shall be provided with overcurrent protection, i.e. a fuse or circuit-breaker, at the point of connection to the main panel-board bus", if the fused plugs that will be used with it do not count as being "at the point of connection to the main panel board bus".
 
Vic, read Daydreamers posts more carefully. He is NOT talking about overcurrent. We are all agreed that there should be an RCBO in there for the whole circuit. He is now talking about a SEPARATE isolator to switch the system off - this is what I am saying is unnecessary. They are fitted to houses only because you cannot unplug a house to work on the circuit.

So the system should be something like:
Shore -> socket -> CU -> RCBO (whole boat) -> MCB (per circuit) -> sockets or lights
Daydreamer is asking if, like a house, we should have:
Shore -> socket -> CU -> Isolator switch -> RCBO (whole boat) -> MCB (per circuit) -> sockets or lights

And I am saying that the isolator is not necessary on a smallish boat because you would just remove the power source. Obviously if there's a generator on board this may change.
Dave
 
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