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Old 11-15-2012, 01:06 PM   #21
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A couple of Bridge rectifiers at about $5.00 each and a hunk of aluminum angle and some wire about a $20.00 investment vs a couple of hundred for a factory one.

It does exctly the same thing.

Not looking for permission here. It is just me. I like to know how things work and why.

Great idea Av8r of a light on the unit (constant on) just to tell me the thing is doing what it is supposed to do is a great idea.
I will install it this weekend.

Such a simple thing.

Sd
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Old 11-15-2012, 02:09 PM   #22
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If the light connected to the ship side of the isolator goes out it shows there is no longer a connection between theground and the neutral
Or, more likely, it will continue to flicker intermittently because the reason the GI failed is likely from a ground fault taking out the diodes and that ground fault now has no way to go directly to earth and is energizing the housings of every piece of AC equipment, the engine block, and through that to the negative side of the DC distribution circuit.

It only flickers intermittently because the seawater that now serves as a conductor between all the parts connected by that pesky green bonding wire and the earth can be kind of an iffy conductor. Someone touching the dock and a grounded metal part of the boat would allow it to glow properly.
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Old 11-15-2012, 02:40 PM   #23
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SD--- We had a brand-name galvanic isolator installed on our boat many years ago. They are actually not very expensive at all. What IS expensive is an isolation transformer.

A galvanic isolator if properly built and installed will protect your boat from leaking current in the ground power from the dock. Like if some other boat or a dock wiring fault is allowing current to get into the ground wire.

But a galvanic isolator will not do anything to protect your boat from stray current in the water itself. If such a current is present in your slip, in extreme circumstances it can make short work of propellers, through hulls, etc. The only way to combat this is with an isolation transformer and they are major dollars.
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Old 11-15-2012, 02:54 PM   #24
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The only stray current I have experienced is what I think was a boat over zinced

It turned my propeller white and it would not scrape or sand off.

I never figured out what it was but a year later the prop is fine. No white

SD
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Old 11-15-2012, 03:22 PM   #25
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............. The only way to combat this is with an isolation transformer and they are major dollars.
So why not make your own? All you need is a bunch of wire and some iron cores.
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Old 11-15-2012, 03:53 PM   #26
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Now you're talking Troll old boy!
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Old 11-15-2012, 04:07 PM   #27
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So why not make your own? All you need is a bunch of wire and some iron cores.
Ha! Ha! come on man.

As far as that go's just build your own boat.

We are talking apples and oranges here.

A galvanic isolator is a simple thing. Off the shelf componets at any electronics store.

sd
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Old 11-15-2012, 04:25 PM   #28
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Be careful SD, they don't like it when you crack their ricebowls or bust their myths.

Can't be letting normal people look behind the curtains and smoke screens.
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Old 11-15-2012, 05:46 PM   #29
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Or, more likely, it will continue to flicker intermittently because the reason the GI failed is likely from a ground fault taking out the diodes and that ground fault now has no way to go directly to earth and is energizing the housings of every piece of AC equipment, the engine block, and through that to the negative side of the DC distribution circuit.

It only flickers intermittently because the seawater that now serves as a conductor between all the parts connected by that pesky green bonding wire and the earth can be kind of an iffy conductor. Someone touching the dock and a grounded metal part of the boat would allow it to glow properly.
Thus the boat and shore will be turned into the two sides of a large electrolytic cell, producing hydrogen, oxygen, and chlorine gas.
A prudent mariner would avoid a vessel with streams of bubbles coming from the metal fittings below the waterline, especially if accompanied by a distinct chlorine odor. A rapid departure of the area would be in order.
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Old 11-15-2012, 10:46 PM   #30
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I visited your link .... Never hire a marine electrician or buy electrical equipment built by someone who uses the term "electrolysis" incorrectly.
I believe that Anne-Marie (Yandina) is a retired electronics engineer from Australia.

She has been quite prevalent in on line forums and e-mail groups for a long time. She has some interesting and strong opinions about the ABYC.
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Old 11-16-2012, 06:11 PM   #31
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A couple of Bridge rectifiers at about $5.00 each and a hunk of aluminum angle and some wire about a $20.00 investment vs a couple of hundred for a factory one.

It does exctly the same thing.

Not looking for permission here. It is just me. I like to know how things work and why.

Great idea Av8r of a light on the unit (constant on) just to tell me the thing is doing what it is supposed to do is a great idea.
I will install it this weekend.

Such a simple thing.

Sd
Why are you giving me a hard time? I'm the one who took your side saying that you could build it and it wouldn't void your insurance.

Building or buying a product doesn't make one a better or worse person.

Let me ask you this: Do you know how to cook? Do you sometimes just go out to a restaurant and pay someone else to cook a meal for you?

Same thing, isn't it?
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Old 11-16-2012, 06:14 PM   #32
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Now you're talking Troll old boy!
Two common doorbell transformers connected back to back (connect the 24volt terminals together) will make an isolation transformer. Now all you need to do is parallel enough ot them to handle the 30 or 50 amps you need for your boat.
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Old 09-28-2016, 09:40 PM   #33
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I believe that Anne-Marie (Yandina) is a retired electronics engineer from Australia.

She has been quite prevalent in on line forums and e-mail groups for a long time. She has some interesting and strong opinions about the ABYC.
and yet she still does not know what "electrolysis" is.
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