Generator ground

[VicS]

I have an MCB and RCCB fitted on my 230v shore supply, this should give full protection should the earth path fails.

The mcb will give you overcurrent protection, as a fuse would.

An rccb or rcd relies on a return path to the neutral of the power source. Normally via the earth conductor. If this fails the connection to the water will still be sufficient for an rccb to operate oorrectly.

 

[billskip]

The mcb will give you overcurrent protection, as a fuse would.

An rccb or rcd relies on a return path to the neutral of the power source. Normally via the earth conductor. If this fails the connection to the water will still be sufficient for an rccb to operate oorrectly.

One could ask the question...if there wasn't an earth/ground how would one get a shock ?
Ground/earth Bonding is suppling a conductor which offers a greater opportunity for shock.

However ground/earth bond supplies a conductor which could (and I believe has )
prevent a fire should a component fail if an rcd is fitted.

 

[rogerthebodger]

The mcb will give you overcurrent protection, as a fuse would.

An rccb or rcd relies on a return path to the neutral of the power source. Normally via the earth conductor. If this fails, the connection to the water will still be sufficient for an rccb to operate correctly.

This is my point that the earth connector is the main return path in any fault condition and the connection to th water as promoted by Paul is an alternative patch if the wired earth patch.

I the case of a generator on a boat the only earth path is the wired earth internally and as I have an earth fault indicator on board so with internal generators its the internal earth that hyper important.

A simple connection of the earth wire to the water from an internal generator does not provide an alternative earth patch back to the neutral point on the generator so really does not provide any additional safety which is unlike the alternate ground return path does in a land installation.

This is important with a land installation as we do not have control or knowledge of the wired earth path outside out house /shed or other propriety, so a plan B is not just important but is imperative. GRP boats and cars camper vans are different due to the isolating inherent in the construction of the vessel / vehicle.

There is no harm in connecting a GRP hull to the water but where do you connect that water connection is made and how do you know if it's a protection preventing any electric shock.

My approach is to ensure the wired protective earth (return path) is under my control inside my boat and to ensure that return path has no fault by having and return path fault detector which in my case is a green neon indicator connect between the generator line and the return path wire.

I also have a red neon indicator between the neutral and the wited return path (earth) in the incoming shore power line. This is not required on an internal generator as there cannot ever be a reverse polarity with an internal generator unless wired incorrectly.

We do not know if the shore power jetty connection is connected correctly hence the need for a reverse phase indicator

On my steel boat as the hull is conductive, I do have a connection to the conductive hull together with a galvanic isolator to prevent galvanic currents flowing in my hull eroding my anodes excessively

 

[RogerJolly]

I sometimes think I'll try getting to grips with the ins and outs of mains electricty and earthing.

This thread has made the project seem so complex as to be hopeless - my ambition has been killed like those baby walruses killed by males fighting to be the alpha.

 

[lustyd]

GRP boats and cars camper vans are different due to the isolating inherent in the construction of the vessel / vehicle

This is dangerous misinformation. You have ZERO control in an environment surrounded by seawater which may or may not be inside of the boat at any given moment.

Please stop posting, the regs are there precisely because of this sort of nonsense to ensure that people have something sensible to follow.

 

[Alex_Blackwood]

https://dms.niceic.com/0000003348.pdf

 

[rogerthebodger]

This is dangerous misinformation. You have ZERO control in an environment surrounded by seawater which may or may not be inside of the boat at any given moment.

Please stop posting, the regs are there precisely because of this sort of nonsense to ensure that people have something sensible to follow.

No, I will not stop expressing my opinion which I see is based on sound knowledge and theory than most included the so-called professionals claim.

I have been involved in both development and application of British standards and understand how general they tend to be to cover the most common applications where I talk about specific applications.

It clear you don't understand by fact that you posted a question, and I posited my opinion. If you don't wish to take my option is your choice but the forum is where alternate vies can be promoted and it only advice not compliancy.

Having been a member of the Instruction of Mechanical Engineers until I retired, I could be help legally accountable for my engineer work and recommendations and qualified in both Mechanical and Electrical Engineering I have knowledge and long experience in both fields.

I do not be leave you can stop me from posting my opinion bast on long and extensive knowledge

 

[lustyd]

https://dms.niceic.com/0000003348.pdf

This is a document aimed at mitigating situations where earthing is difficult or impossible on land in well managed scenarios.

None of that is true on a boat where people may be comfortably living, oblivious to the dangers, and where earthing is trivially easy.

 

[lustyd]

It clear you don't understand

I absolutely understand. Do you understand what happens when your bilge is full of water? Your theory would go out of the window immediately and you'd likely be electrocuted.

I do not be leave you can stop me from posting my opinion bast on long and extensive knowledge

You're wrong there. I can ask the @Forum Admin Team to close my thread for replies as it's drifted far from the question and poses a danger to any readers you might mislead.

 

[rogerthebodger]

https://dms.niceic.com/0000003348.pdf

Interesting I will study that Later today when I had time

Fig 2 in that document is basicly how my systen is designed around

 

[rogerthebodger]

This is a document aimed at mitigating situations where earthing is difficult or impossible on land in well managed scenarios.

None of that is true on a boat where people may be comfortably living, oblivious to the dangers, and where earthing is trivially easy.

Thats your opinion but still needs to be considered

As I said I wish to study the document properly and not make snap decisions just because its differs from you preconceived ideas again conformation bias

 

[lustyd]

Thats your opinion but still needs to be considered

I did consider following the advice for land based installs where earthing is hard. I choose to follow boat based advice and regulations for where proper earthing is very easy. Not everything needs to be done the hard way, sometimes the regs are sensible and easy to follow.

 

[rogerthebodger]

I absolutely understand. Do you understand what happens when your bilge is full of water? Your theory would go out of the window immediately and you'd likely be electrocuted.

You're wrong there. I can ask the @Forum Admin Team to close my thread for replies as it's drifted far from the question and poses a danger to any readers you might mislead.

You can but gain it's your view that my posts ins danger and is misleading.

I also can ask the Forum Admin as I have before. I live in a free world do you

Do you understand what happens when your bilge is full of water?

Yes I do and it it carries any mains current my RCD would trip and cut the power and prevent and further danger

 

[lustyd]

it's your view that my posts ins danger and is misleading.

It is, but I also hope that one day you don't find yourself lying in a pool of your own urine thinking "in theory I shouldn't have been electrocuted".

Better safe than sorry, especially with well proven and well understood safety systems

 

[billskip]

the regs are there.

Exactly, one must conform to the regulations, it doesn't mater a jot what anyone else thinks or believes.

If it doesn't conform to the regulations it is unlikely to get a certificate to satisfy the insurance company or any other official body that requires such a certificate.

That said the regulations differ or may not even exist in some countries.

I wonder sometimes who on here can explain the reason for the earth/ground bonding,

I'll get my popcorn

 

[PaulRainbow]

I sometimes think I'll try getting to grips with the ins and outs of mains electricty and earthing.

This thread has made the project seem so complex as to be hopeless - my ambition has been killed like those baby walruses killed by males fighting to be the alpha.

It isn't complicated, it's just made to sound that way by one person who posts dangerous misinformation.

 

[rogerthebodger]

I did consider following the advice for land based installs where earthing is hard. I choose to follow boat based advice and regulations for where proper earthing is very easy. Not everything needs to be done the hard way, sometimes the regs are sensible and easy to follow.

So, in detail how safer is you setup than mine

I have repeated asked Paul to do the current flow analysis, and he has refused, I do consider why, I have my opinion but will not express it here on a public forum.

It is, but I also hope that one day you don't find yourself lying in a pool of your own urine thinking "in theory I shouldn't have been electrocuted".

Better safe than sorry, especially with well proven and well understood safety systems

Again, you are making unfounded statement that my system is dangerous without providing any factual evidence just based on your own assumptions your assumption is that any way different to your way is dangerous which is just scaremongering

The only way is to analysis the current flow in the particular circumstances and not just based on what the various standards state that you subscribe to.

You need to study like me all the various electrical distribution systems are designed and configured

 

[Sandro]

I do not want entering a long argument, just say I disagree with this sentence in post #8: "If you're standing in a GRP boat and you touch a live wire, you get a shock." by PaulRainbow (whom otherwise I fully esteem).
If you are standing on an insulated base, as the GRP hull or floor, and you touch with only one point - a finger for instance - a live wire, all your body will get the potential of the wire but no current will flow through it. You would not even notice.
Excuse the fastidiousness.

Sandro

 

[lustyd]

I do not want entering a long argument, just say I disagree with this sentence in post #8: "If you're standing in a GRP boat and you touch a live wire, you get a shock." by PaulRainbow (whom otherwise I fully esteem).
If you are standing on an insulated base, as the GRP hull or floor, and you touch with only one point - a finger for instance - a live wire, all your body will get the potential of the wire but no current will flow through it. You would not even notice.
Excuse the fastidiousness.

Sandro

Unless it's wet on your boat, then you might die.


Paul has explained in the past why RCDs won't work, go and search

 

[PaulRainbow]

I do not want entering a long argument, just say I disagree with this sentence in post #8: "If you're standing in a GRP boat and you touch a live wire, you get a shock." by PaulRainbow (whom otherwise I fully esteem).
If you are standing on an insulated base, as the GRP hull or floor, and you touch with only one point - a finger for instance - a live wire, all your body will get the potential of the wire but no current will flow through it. You would not even notice.
Excuse the fastidiousness.

Sandro

You are mistaken, i have personally had electric shocks whilst standing in a GRP boat.