Galvanic isolator

Ripster

Ripster

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Does anyone happen know whether there is a Galvanic Isolator fitted as standard to the Jeanneau Prestige 32 and if so where it is? I want to make sure there is one, but have not searched the boat yet to try and check if there is already one fitted or I need to fit one. Thought I would ask here first..!
 
Knowing Jeanneau, it's doubtful. It's also doubtful that it's covered in the specs, at least it isn't on my MF805. I've only had half a look on mine, must finish checking, but the impression that i got was there isn't one. If you can check where the shore power comes in you should find a junction box of some sort. My interpretation is that if the AC earth comes to the junction box and then gets branched off to all the AC installations, there won't be an isolator. AC earth should go to the isolator, then to the junction box/distribution panel etc.

You'd also need to check though to see if the AC earth is connected to the bonding circuit at some point. Strictly speaking, as i understand it, if the AC earth isn't connected to the bonding circuit you don't need a galvanic isolator. This may depend on the year in which the boat was built.

I'm assuming two things with mine, until i can verify, and that is that it has no isolator and the AC earth isn't connected to the bonding circuit. Which leaves me undecided, do i leave it as it is, been fine since 2003 when it was built, or do i fit one and connect the bonding and AC earths together ?
 
PaulGooch said:
You'd also need to check though to see if the AC earth is connected to the bonding circuit at some point. Strictly speaking, as i understand it, if the AC earth isn't connected to the bonding circuit you don't need a galvanic isolator. This may depend on the year in which the boat was built.

I'm assuming two things with mine, until i can verify, and that is that it has no isolator and the AC earth isn't connected to the bonding circuit. Which leaves me undecided, do i leave it as it is, been fine since 2003 when it was built, or do i fit one and connect the bonding and AC earths together ?
Click to expand...

That's my understanding too, I was going to ask the same question in a previous thread, look forward to the answer as I've been thinking along similar lines with my Bene 9.
 
Our Prestige 36 which is now 5 years old did not have a galvanic isolator fitted by Jeanneau, I am fairly sure that Jeanneau don't fit one as standard to any boat in the range.
They are not difficult to fit and are also only about a £100 to buy. To check if you have one fitted just follow the earth wire from the transom anode and see what its connected to.
 
If you have an isolator fitted the incoming AC earth should be connected to the isolator before it goes anywhere else. The output from the isolator will then go to the various AC earthing points throughout the boat, as well as having a cable from somewhere on the boats earthing circuit connecting to somewhere on the bonding circuit. The bonding circuit being the connection between all of the metal items that are connected together and to the transom anode.

So as far as i can tell, the easiest way to check if you have one is to follow the shore power cable into the boat. If the earth wire goes to a terminal box/junction box, you don't have an isolator (unless someone has put it in the wrong place).

It's interesting and a little disturbing that they are not fitted as standard, or is it because they don't run the earth to the bonding circuit ? Anyone remember when it became a requirement to do so ?
 
PaulGooch said:
If you have an isolator fitted the incoming AC earth should be connected to the isolator before it goes anywhere else. The output from the isolator will then go to the various AC earthing points throughout the boat, as well as having a cable from somewhere on the boats earthing circuit connecting to somewhere on the bonding circuit. The bonding circuit being the connection between all of the metal items that are connected together and to the transom anode.
Click to expand...

No isolator on mine, incoming earth goes straight to consumer unit. Don't have a transon anode either, only anodes are rudder, prop and skeg.
 
Philiz said:
No isolator on mine, incoming earth goes straight to consumer unit. Don't have a transon anode either, only anodes are rudder, prop and skeg.
Click to expand...

Mine are on the prop and skeg, with one also on the transom. The bolt comes all the way through the transom and on the inside it has a cable to an earthing point. From the earthing point cables go off to various bits of metal (rudder, engine and some other stuff).

From what i've read, some later regs require the incoming AC earth to be connected to the bonding circuit. It's this connection that means lecky faults on adjoining boats or the marinas shore power systems will dissolve your metal bits.

This explains it better : http://www.sterling-power.com/products-galvanic-why.htm

I'm becoming inclined to think that if were are not connecting the AC earth to the bonding circuit/hull etc then we needn't worry. I certainly don't have an isolator, but i'll double check to see if my AC earth is connected to the bonding circuit.
 
Philiz said:
Interesting, I was looking at my mates MF805 on tuesday. Anodes on the prop and the transom but none on the skeg as I saw. Actually the one on the prop had fallen off (so as mine) so maybe his skeg one had too!
Click to expand...

Mine didn't have one on the prop when i bought it. The allen bolt in the end was tight, so it hadn't been eaten away. No signs of any problems, but i put one on anyway. Not sure how much the skeg really needs one, it only makes contact with the GRP, but again i fitted a new one.
 
Going on what being said, I defo do not have one before SP hits the breaker. I do have a transom anode and 4 large ball shaft anodes and 2 propnut anodes and one on each trim tab! £200 worth anodes for a complete change of all. And one of the BT prop nut too.

I will have a final look over the boat at the WE to double check its not been put in wrong place, but will be surprised to find anything.

Thanks to all for the input.
 
isolator

Did not have one on our 08 J32. We did have corrosion issues due to lack of proper grounding wires and ended up with pink props. Once fixed, we had Jeanneau put on large transom anode. No issues after that was installed. IMHO, I would put one on to be safe and get isolator. Cheap, easy to install...good insurance.
 
Defo no GI on there that I can find. But, on the up side looks very easy to access and fit one. So thats a job over Easter then!
 
Ripster said:
Defo no GI on there that I can find. But, on the up side looks very easy to access and fit one. So thats a job over Easter then!
Click to expand...

Likewise on my MF805, after reading that they didn't fit one on Yankee1's 08 32 it doesn't surprise me that we don't have them. I already have a transom anode, but it would be worth you looking into fitting one IMO.
 
Good advice on the Transom anode - but In fact I already have one and there are lots of earth wires attached to it! I know this very well as I managed to unseat the bolt that holds it on and had to redo and reseal the whole thing! Also checked the conductivity of the connections etc to the bonding circuit and all seems good.
 
Ripster said:
Good advice on the Transom anode - but In fact I already have one and there are lots of earth wires attached to it! I know this very well as I managed to unseat the bolt that holds it on and had to redo and reseal the whole thing! Also checked the conductivity of the connections etc to the bonding circuit and all seems good.
Click to expand...

Ah, same as mine then. After fitting the isolator, you can connect the AC earth to the bonding circuit.

This looks a good price :

http://www.marine-super-store.com/posit/shop/index.php?selectedpartno=99051587
 
Former Jeanneau Dealer here

No GI is fitted.

You will have hull anode (small, refit with bigger next year)
a prop anode on the end of each prop / shaft
bow thruster anode if BT fitted
engine anodes (err in the engine)
You should have anodes on your trim tabs (if you have tabs), not everyone fits them.

Obviously you have battery isolators and you should try and turn them off when you leave the boat. Leaving the boat plugged in to shore power, batteries and battery charger on is not a great idea.
You should need a GI if you look after the boat properly. Leave everything put to bed properly and your anodes will help take care of the boat. If in an area / marina of bad electrolysis, rig a very large pear anode, earth it to the boat and chuck it over the side when in the marina. This will slow things down a lot.

GI's are an unusual thing to find fitted as standard to boats. They are readily available and can be tapped into the system quite easily, but not enormously necessary.

Tom
 
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