Electrical leak

sailinglegend420 said:
Do yourself and us a big favour and buy a digital voltmeter - about £10 - and measure the voltage that was giving you the tingle. If it's around 20 volts AC that's probably an earth problem somewhere, if it's 240 volts AC that means your charger is connecting the Live wire to your boat DC negative.!!!!!!
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I have one on board but I didn't know what to measure nor the possible cause. I don't know why this is doing you a favour I only came here for advice. earlier I was accused of being a troll!

I am sure it is not 240V as I could not feel it with my fingers , it is probably less than 50V. So I plan to measure earth to anode and then neutral to anode with charger switched both on and off. I am am also going to see if I can find out if a galvanic isolated is fitted and if not I will fit one. I can't think of anything else to do at this stage. I didn't think I will be able to trace out the fault if that is not the cause because everything is so difficult to get to.
 
Seven Spades said:
I have one on board but I didn't know what to measure nor the possible cause. I don't know why this is doing you a favour I only came here for advice. earlier I was accused of being a troll!

I am sure it is not 240V as I could not feel it with my fingers , it is probably less than 50V. So I plan to measure earth to anode and then neutral to anode with charger switched both on and off. I am am also going to see if I can find out if a galvanic isolated is fitted and if not I will fit one. I can't think of anything else to do at this stage. I didn't think I will be able to trace out the fault if that is not the cause because everything is so difficult to get to.
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As others have said... get an electrician. Very quick job to check things over and you will get your list of recommendations that you can then consider or find out if the system is condemned! Why faff around with something new to you? Watch him/her and learn for a couple of quid spent.
 
Seven Spades said:
...earlier I was accused of being a troll!
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Only because you didn't seem to get the basic difference between a proper mains installation and having a line led aboard with sockets hanging off it.

That was later explained so no problem; don't dwell on it :-).

My set up is just the line but it is hardly ever used; I still run an RCD off it though.

My house had something similar - I have several outhouses (distant from house) and in one there was a tingle on some exposed metalwork. Got leccy in and turned out the earth spike was mostly corroded so was a quick fix, but he did say it could have been MUCH worse and lucky to find at that stage.
 
Just popped back to see how you are getting on with this wind up. Still believe your a troll, no one can be that Nieve, or can they? My last electrical contract job was as the electrical contracts manager for local council, and quite an eye opener on both the supply system and end user issues. If you are genuine, and I really can't believe you are, then get yourselft an electrician before you kill yourself!
 
Jean said:
Just popped back to see how you are getting on with this wind up...
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Why do you think it's a wind up? The OP was just confused by the term "fixed installation", and nobody has elaborated.

A fixed installation is where there is a power-in socket on the boat that you plug your shore-power lead into. Internally there should be a RCD (Residual Current Device) or ELCB (Earth Leakage Circuit Breaker), with possibly internal wiring for power sockets, water heater, charger etc.

The alternative is just an extension lead like you would use at home, and you plug in whatever you want to power.
 
It does seem from the comments by seven spades that he has a simple arrangement of mains cord from the yard outlet to his battery charger.
Now if you were running say a little blower heate all plastic no metal parts then there should be no problems.
With a battery charger you have a negative wire from the charger to your battery negative and so then to the engine prop etc.
Now we would hope that the negative outlet terminal is isolated from the mains earth coming in from the marina outlet. If it is not and this is often happens. Like the metal box is connected to the mains earth and the engative wire contacts the box or the box contacts something negative on the boat.
Theoretically the earth wire coming in from the yard outlet should be well connected to the actual earth with a ground stake. However if any device any where in the yard has leakage to earth there can be acurrent flow in the earth system causing a volt drop and so some voltage on the earth wire. Much worse if the earth ground stake is not effective.
You say the tingle goes if you switch off the charger. Does that mean also disconnect the power lead form the charger? If it only dissapears with unplugging but is there with charger not charging then there may be voltage coming in on the earth wire. If it is only there when the charger is on and the + and - wires are disconnected from the battery then it looks like a faulty charger. If the tingle is there only with charger charging it still amy be a bad charger. Try another charger.
Now for seven spades I have only talked about a charger ona lead from power outlet.
Many people have a fully installed ring mains system often including a hard wired storage water heater battery charger and built in power outlets. This is where a residual current safety switch is used. The mains earth is connected to the negative of the boats systems. (All earths.) Now when using this sytem for 24/7 connection there is the possibility of the marina's earth system using your boat as an earth in lieu of the obligatory earth stake. This current often quite small can cause galvanic damage to props etc.
A galvanic isolator is a device which makes an earth connection if there is a fault and lots of current flows. But will isolate and not make a connection for small voltages less than about 2volts. This may stop these small currents from damaging prop etc. IMHO not needed for just occasional short time battery charging. good luck olewill
 
William_H said:
Many people have a fully installed ring mains system often including a hard wired storage water heater battery charger and built in power outlets. This is where a residual current safety switch is used. The mains earth is connected to the negative of the boats systems. (All earths.) Now when using this sytem for 24/7 connection there is the possibility of the marina's earth system using your boat as an earth in lieu of the obligatory earth stake. This current often quite small can cause galvanic damage to props etc.
A galvanic isolator is a device which makes an earth connection if there is a fault and lots of current flows. But will isolate and not make a connection for small voltages less than about 2volts. This may stop these small currents from damaging prop etc. IMHO not needed for just occasional short time battery charging. good luck olewill
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This is what I have, ring main water heater, the lot. Thanks for the advice I now have some testing to do.
 
Jean said:
Just popped back to see how you are getting on with this wind up. Still believe your a troll, no one can be that Nieve, or can they? My last electrical contract job was as the electrical contracts manager for local council, and quite an eye opener on both the supply system and end user issues. If you are genuine, and I really can't believe you are, then get yourselft an electrician before you kill yourself!
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No need to be rude?

And yes, I humbly suggest that people can be that naive about electricity. I'm surprised that you didn't appreciate that if you were an electrical contracts manager.
 
nigelmercier said:
I'm yet to be convinced that this offers any advantages, and has a whole bucket of disadvantages.
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The reason for connecting the boats Negative / Galvanic Bonding circuit to the AC earth is provided here - Page 164 and particularly Page 165. I appreciate this refers to the American ABYC standars, but apart from the frequency, electricity in the US obeys the same rules of physics.

My system wil remain bonded between AC & DC.

https://www.dropbox.com/s/n74qpmuw40jlods/Boatowner's Illustrated Electrical - Charlie Wing.pdf
 
superheat6k said:
The reason for connecting the boats Negative / Galvanic Bonding circuit to the AC earth is provided here - Page 164 and particularly Page 165.
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Yes - it shows that if you join the two earths there are a lot more possible ways to electrocute yourself if something goes wrong with the mains supply.
 
JumbleDuck said:
Yes - it shows that if you join the two earths there are a lot more possible ways to electrocute yourself if something goes wrong with the mains supply.
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But their is only one earth, ground call it what you will. Have two (one of which must by definition be a false one) in close proximity and the hazard should be obvious. This principle is also supported by Calder and most other authorities on the subject of boat electrical safety.

Surprisingly a subject that as yet does not, as I understand it, have an EU Directive / Regulation dictating what we must do, as I am not sure the Recreational Craft Directive covers this area. ABYC works for me, albeit with EU harmonised colours, as explained so well by Calder.
 
Seven Spades said:
This is what I have, ring main water heater, the lot. Thanks for the advice I now have some testing to do.
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Seven Spades, I will be very interested in your findings, as we have the same boat and the same setup. I am not aware of any galvanic isolator on the boat. When I bought the boat, the prop turned out to be pitted, most probably galvanic corrosion. The boat had been in a marina without moving for over six months, presumably plugged into the mains and had been next to a big steel boat all the time.
So far I haven't changed the electrical setup. I normally do not leave the boat plugged in when I am not aboard. I do find that the prop anode wears away significantly over just one season. The hull anode appears not to be affected.
 
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