Galvanic isolater

[cutandpolished61]

Hi All, I'm wondering if I have to use a galvanic isolater when powering a battery charger with a portable generator on my  narrow boat?

[Tony Brooks]

5 minutes ago, cutandpolished61 said:

Hi All, I'm wondering if I have to use a galvanic isolater when powering a battery charger with a portable generator on my  narrow boat?

 

Where will the generator be sites when running, will you be using an earth spike, and can the generator metal parts come into contact with the ground if running off the boat. There is a good chance that the answer is no, unless the generator is, in some way, earthed to the bank.

[cutandpolished61]

The generator would be placed on the cruiser stern near the battery bank. The generator would have no direct contact to the boat but the power cable from the generator to the battery charger would 

[Alan de Enfield]

7 minutes ago, cutandpolished61 said:

The generator would be placed on the cruiser stern

 

That is a really bad idea and strongly discouraged by both C&RT and the BSS

Petrol gennies are the worst !

 

Folks have died from CO poisoning by doing just that.

 

Read the BSS warnings on their webpage.

Edited October 26 by Alan de Enfield

[cutandpolished61]

I have an 4 ft exhaust fitted. The generator would be placed on the cruiser stern near the battery bank. The generator would have no direct contact to the boat but the power cable from the generator to the battery charger would 

[Alan de Enfield]

9 minutes ago, cutandpolished61 said:

I have an 4 ft exhaust fitted.

 

Even worse - DIY exhausts on portable generators are extremely bad news (maybe quit whilst you can)

 

A boater in the Lake district did that - surprisingly he was a qualified gas-safe engineer and should have known better,  however, it didn't stop him killing his girlfriend and daughter with CO poisoning.

[Tony Brooks]

9 minutes ago, cutandpolished61 said:

I have an 4 ft exhaust fitted. The generator would be placed on the cruiser stern near the battery bank. The generator would have no direct contact to the boat but the power cable from the generator to the battery charger would 

 

In that case, there is no need for a galvanic isolator.

 

I echo the warning that Alan and CaRT give you, however long the exhaust may be. A chap in the lake district killed someone by using a generator with a modified exhaust on his boat.

[cutandpolished61]

Thanks for the advice. I have even an air quality meter installed on my boat which I monitor regularly as I'm always suspicious of the stove. 

[Gybe Ho]

13 minutes ago, cutandpolished61 said:

Thanks for the advice. I have even an air quality meter installed on my boat which I monitor regularly as I'm always suspicious of the stove. 

 

The problem with CO poisoning is that it impairs your ability to think, monitor and act.  High CO2 levels trigger a different reaction because the body senses a problem and triggers an alert reaction in the body, this is why people suffering from sleep apnea wake up choking and alarmed.

[nb Innisfree]

34 minutes ago, cutandpolished61 said:

Thanks for the advice. I have even an air quality meter installed on my boat which I monitor regularly as I'm always suspicious of the stove. 

On Innisfree I fitted a Co detector, it kept informing via a silent led alarm of low level CO, took us ages of observation to spot a, small amount of smoke drifting into a mushroom vent in a certain wind direction, a removable metre high chimney was the only solution. 

 

I often wonder how many boaters are unaware of low level CO, for us there were no symptoms. 

[David Mack]

2 hours ago, cutandpolished61 said:

The generator would have no direct contact to the boat

Really? Hanging from skyhooks then?

 

If you have an 230V ac source of power the earth of the power system should be deliberately grounded to the boat hull. If your generator has a neutral to earth bond, then the generator chassis would be connected to the boat hull anyway via the ground bond, so any incidental electrical contact won't matter. If the generator has a centre tapped earth then that will be insulated from the generator chassis, so again incidental contact won't matter.

[jonathanA]

Not withstanding the exhaust issue. Whether the genny is in contact with the boat or on shore with an earth spike. The galvanic issue is to do with sharing earths with other boats via mains supplies. 

That's not the case here so no issue for the op IMHO.

[GUMPY]

14 minutes ago, jonathanA said:

The galvanic issue is to do with sharing earths with other boats via mains supplies. 

That's not the case here so no issue for the op IMHO.

Nearly right.

 

Any boat connected to shore mains without some form of protection can suffer galvanic corrosion even if there are no boats nearby, metal piling can give  the same effect.

[Tony Brooks]

1 minute ago, GUMPY said:

Nearly right.

 

Any boat connected to shore mains without some form of protection can suffer galvanic corrosion even if there are no boats nearby, metal piling can give  the same effect.

 

and I believe nearby heavy current users, like industrial processes etc. I suspect it is also affected by how the "earth" is derived at the location.

[Alan de Enfield]

8 hours ago, cutandpolished61 said:

Thanks for the advice. I have even an air quality meter installed on my boat which I monitor regularly as I'm always suspicious of the stove. 

 

Having just copmpleted my Oxygen administration and rescue course I can inform you that very very small amounts of CO can attach themselves to your haemaglobin 200 times more effectively than Oxygen leaving fewer and fewer molecules of haemaglobin available to carry the O2 - you don't even know it is happening as it stops your blood carrying Oxygen, you get headaches and drift off to sleep never to wake up again.

It is also cumulative so the (say) 50ppm just build up and up over the period - you don't breathe it out like you do with Carbon Dioxide.

 

Small generators and 'petrol powered garden equipment' run quite rich and apparently puts out some 10% (100,000ppm) of the exhaust gas as CO.

A well maintained car enginbe with a catalytic convertor puts out ~ 15ppm

 

It is called the silent killer for a reason.

 

 

 

From the BSS

 

These are the core points that should never be forgotten.

• Never install a portable generator permanently or make unauthorised modifications that are not supported by the manufacturer, or proprietary component supplier.

• Never run generators on the boat, or on the bank near to doors, vents, windows and hatches. If you can smell exhaust fumes in the boat, it could mean the cabin is also filling with deadly carbon monoxide.

• Never refuel any generator anywhere aboard the boat; take it to the bank and ensure you are a safe distance from other boats and potential sources of ignition.

Edited October 26 by Alan de Enfield

[jonathanA]

2 hours ago, GUMPY said:

Nearly right.

 

Any boat connected to shore mains without some form of protection can suffer galvanic corrosion even if there are no boats nearby, metal piling can give  the same effect.

Nearly right....😊

 

The piling would need to connected to the same mains earth system or be touching ( in contact) with the boat.

 

From the op posts neither of these would appear to be the case.

 

[Alan de Enfield]

20 minutes ago, jonathanA said:

The piling would need to connected to the same mains earth system or be touching ( in contact) with the boat.

 

Goat chains and nappy pins would make the connection.

[GUMPY]

25 minutes ago, jonathanA said:

The piling would need to connected to the same mains earth system

The clue is in the word Earth 

[ditchcrawler]

5 hours ago, Alan de Enfield said:

 

Having just copmpleted my Oxygen administration and rescue course I can inform you that very very small amounts of CO can attach themselves to your haemaglobin 200 times more effectively than Oxygen leaving fewer and fewer molecules of haemaglobin available to carry the O2 - you don't even know it is happening as it stops your blood carrying Oxygen, you get headaches and drift off to sleep never to wake up again.

It is also cumulative so the (say) 50ppm just build up and up over the period - you don't breathe it out like you do with Carbon Dioxide.

 

Small generators and 'petrol powered garden equipment' runs quite rich and apparently puts out some 10% (100,000ppm) of the exhaust gas as CO.A well maintained car enginbe with a catalytic convertor puts out ~ 15ppm

 

It is called the silent killer for a reason.

 

 

 

From the BSS

 

These are the core points that should never be forgotten.

• Never install a portable generator permanently or make unauthorised modifications that are not supported by the manufacturer, or proprietary component supplier.

• Never run generators on the boat, or on the bank near to doors, vents, windows and hatches. If you can smell exhaust fumes in the boat, it could mean the cabin is also filling with deadly carbon monoxide.

• Never refuel any generator anywhere aboard the boat; take it to the bank and ensure you are a safe distance from other boats and potential sources of ignition.

I hope @Roving Rowan has seen this bit of the thread

[Alan de Enfield]

39 minutes ago, ditchcrawler said:

I hope @Roving Rowan has seen this bit of the thread

 

Why ?

[ditchcrawler]

29 minutes ago, Alan de Enfield said:

 

Why ?

Did you not see the picture of his boat. Sorry it was on FB with a big blue genny standing in the back hatches. 

[Alan de Enfield]

38 minutes ago, ditchcrawler said:

Did you not see the picture of his boat. Sorry it was on FB with a big blue genny standing in the back hatches. 

 

That's why I've not seen it.

O'well there are idiots in all walks of life. Sounds like a strong candidate for the Darwin awards.

[Gybe Ho]

4 hours ago, GUMPY said:

The clue is in the word Earth 

 

The clue is in the word "galvanic". Even if a piling is connected to a narrowboat with a portable genset running, what would drive the galvanic reaction?

 

I am not suggesting you are wrong, but rather than trading insults via emojis why not explain?

7 hours ago, Alan de Enfield said:

 

Small generators and 'petrol powered garden equipment' run quite rich and apparently puts out some 10% (100,000ppm) of the exhaust gas as CO.

A well maintained car enginbe with a catalytic convertor puts out ~ 15ppm

 

 

When a portable petrol generator is converted to run off LPG does that change the risk? I assume not because both petrol and lpg contain hydrogen and carbon chains in different arrangements.

[nicknorman]

12 hours ago, cutandpolished61 said:

Hi All, I'm wondering if I have to use a galvanic isolater when powering a battery charger with a portable generator on my  narrow boat?

You asked a simple question. You didn’t ask for a CO risk assessment. The answer to your simple question is that no, there is no need or point in using a galvanic isolated in the circumstances you describe. End of. 

Edited October 26 by nicknorman

[Roving Rowan]

3 hours ago, ditchcrawler said:

I hope @Roving Rowan has seen this bit of the thread

Thanks for the nod. The jenny was on the back deck to make space in the cabin that day, not in use as the sun was out all day so we where on solar. It sits chained up on the front deck now and exhaust vents away from the boat. There are 6 CO2 alarms on the boat at various heights as well as a bilge gas alarm. The biggest CO2 issue is driving it with the Lister SR3 smoking away from the stack, certainly not invisible but a killer none the less. We use 3M respirators when on the move but it still stings the eyes.